IMT Institutional Repository: No conditions. Results ordered -Date Deposited.
2024-03-28T23:51:50Z
EPrints
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2017-12-28T10:55:54Z
2017-12-28T10:55:54Z
http://eprints.imtlucca.it/id/eprint/3850
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3850
2017-12-28T10:55:54Z
Heart rate variability analysis during muscle fatigue due to prolonged isometric contraction
Summary form only given. Strong light-matter coupling has been recently successfully explored in the GHz and THz 1 range with on-chip platforms. New and intriguing quantum optical phenomena have been predicted in the ultrastrong coupling regime 2, when the coupling strength Ω becomes comparable to the unperturbed frequency of the system ω. We recently proposed a new experimental platform where we couple the inter-Landau level transition of an high-mobility 2DEG to the highly subwavelength photonic mode of an LC meta-atom 3 showing very large Ω/ωc = 0.87. Our system benefits from the collective enhancement of the light-matter coupling which comes from the scaling of the coupling Ω ∝ √n, were n is the number of optically active electrons. In our previous experiments 3 and in literature 4 this number varies from 104-103 electrons per meta-atom. We now engineer a new cavity, resonant at 290 GHz, with an extremely reduced effective mode surface Seff = 4 × 10-14 m2 (FE simulations, CST), yielding large field enhancements above 1500 and allowing to enter the few (<;100) electron regime. It consist of a complementary metasurface with two very sharp metallic tips separated by a 60 nm gap (Fig.1(a, b)) on top of a single triangular quantum well. THz-TDS transmission experiments as a function of the applied magnetic field reveal strong anticrossing of the cavity mode with linear cyclotron dispersion. Measurements for arrays of only 12 cavities are reported in Fig.1(c). On the top horizontal axis we report the number of electrons occupying the topmost Landau level as a function of the magnetic field. At the anticrossing field of B=0.73 T we measure approximately 60 electrons ultra strongly coupled (Ω/ω- ||
A. Guidi
A. Greco
F. Felici
A. Leo
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
M. Bianchi
A. Bicchi
G. Valenza
E. P. Scilingo
2017-12-28T10:50:23Z
2017-12-28T10:50:23Z
http://eprints.imtlucca.it/id/eprint/3849
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3849
2017-12-28T10:50:23Z
A magnetic compatible supernumerary robotic finger for functional magnetic resonance imaging (fMRI) acquisitions: Device description and preliminary results
Summary form only given. Strong light-matter coupling has been recently successfully explored in the GHz and THz 1 range with on-chip platforms. New and intriguing quantum optical phenomena have been predicted in the ultrastrong coupling regime 2, when the coupling strength Ω becomes comparable to the unperturbed frequency of the system ω. We recently proposed a new experimental platform where we couple the inter-Landau level transition of an high-mobility 2DEG to the highly subwavelength photonic mode of an LC meta-atom 3 showing very large Ω/ωc = 0.87. Our system benefits from the collective enhancement of the light-matter coupling which comes from the scaling of the coupling Ω ∝ √n, were n is the number of optically active electrons. In our previous experiments 3 and in literature 4 this number varies from 104-103 electrons per meta-atom. We now engineer a new cavity, resonant at 290 GHz, with an extremely reduced effective mode surface Seff = 4 × 10-14 m2 (FE simulations, CST), yielding large field enhancements above 1500 and allowing to enter the few (<;100) electron regime. It consist of a complementary metasurface with two very sharp metallic tips separated by a 60 nm gap (Fig.1(a, b)) on top of a single triangular quantum well. THz-TDS transmission experiments as a function of the applied magnetic field reveal strong anticrossing of the cavity mode with linear cyclotron dispersion. Measurements for arrays of only 12 cavities are reported in Fig.1(c). On the top horizontal axis we report the number of electrons occupying the topmost Landau level as a function of the magnetic field. At the anticrossing field of B=0.73 T we measure approximately 60 electrons ultra strongly coupled (Ω/ω- ||
Irfan Hussain
Emiliano Santarnecchi
Andrea Leo
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Simone Rossi
Domenico Prattichizzo
2017-12-28T10:39:05Z
2017-12-28T10:39:05Z
http://eprints.imtlucca.it/id/eprint/3847
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3847
2017-12-28T10:39:05Z
Different levels of visual perceptual skills are associated with specific modifications in functional connectivity and global efficiency
The disembedding ability (i.e., the ability to identify a simple masked figure within a complex one) depends on attentional mechanisms, executive functions and working memory. Recent cognitive models ascribed different levels of disembedding task performance to the efficiency of the subtended mental processes engaged during visuo-spatial perception.
Here we aimed at assessing whether different levels of the disembedding ability were associated to the functional signatures of neural efficiency, defined as a specific modulation in response magnitude and functional connectivity strength in task-related areas. Consequently, brain activity evoked by a visual task involving the disembedding ability was acquired using functional magnetic resonance imaging (fMRI) in a sample of 23 right-handed healthy individuals. Brain activity was analyzed at different levels of information processing, from local responses to connectivity interactions between brain nodes, as far as to network topological properties.
All different levels of information processing were significantly modulated by individual behavioral performance. Specifically, single voxel response magnitude, connectivity strength of the right intrahemispheric and interhemispheric edges, and graph measures (i.e., local and global efficiency) were negatively associated to behavioral performance. Altogether, these results indicate that efficiency during a disembedding task cannot be merely attributed to a reduced neural recruitment of task-specific regions, but can be better characterized as an enhanced functional hemispherical asymmetry.
Sabrina Danti
Giacomo Handjaras
Luca Cecchetti
luca.cecchetti@imtlucca.it
Helen Beuzeron-Mangina
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
2017-12-28T10:32:23Z
2017-12-28T10:32:23Z
http://eprints.imtlucca.it/id/eprint/3846
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3846
2017-12-28T10:32:23Z
Functional and spatial segregation within the inferior frontal and superior temporal cortices during listening, articulation imagery, and production of vowels
Alessandra Cecilia Rampinini
alessandra.rampinini@imtlucca.it
Giacomo Handjaras
Andrea Leo
Luca Cecchetti
luca.cecchetti@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Giovanna Marotta
Pietro Pietrini
pietro.pietrini@imtlucca.it
2017-12-28T10:29:31Z
2017-12-28T10:29:31Z
http://eprints.imtlucca.it/id/eprint/3845
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3845
2017-12-28T10:29:31Z
Peripersonal space representation develops independently from visual experience
Our daily-life actions are typically driven by vision. When acting upon an object, we need to represent its visual features (e.g. shape, orientation, etc.) and to map them into our own peripersonal space. But what happens with people who have never had any visual experience? How can they map object features into their own peripersonal space? Do they do it differently from sighted agents? To tackle these questions, we carried out a series of behavioral experiments in sighted and congenitally blind subjects. We took advantage of a spatial alignment effect paradigm, which typically refers to a decrease of reaction times when subjects perform an action (e.g., a reach-to-grasp pantomime) congruent with that afforded by a presented object. To systematically examine peripersonal space mapping, we presented visual or auditory affording objects both within and outside subjects’ reach. The results showed that sighted and congenitally blind subjects did not differ in mapping objects into their own peripersonal space. Strikingly, this mapping occurred also when objects were presented outside subjects’ reach, but within the peripersonal space of another agent. This suggests that (the lack of) visual experience does not significantly affect the development of both one’s own and others’ peripersonal space representation.
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Dario Menicagli
Andrea Leo
Marcello Costantini
Pietro Pietrini
pietro.pietrini@imtlucca.it
Corrado Sinigaglia
2017-09-05T06:41:38Z
2017-09-05T06:41:38Z
http://eprints.imtlucca.it/id/eprint/3781
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3781
2017-09-05T06:41:38Z
The effects of acute, short-term visual deprivation
on low-frequency EEG activity during wakefulness and sleep
Introduction: experimental evidence indicates that regional changes in slow-wave activity (SWA, 0.5-4.5 Hz) during NREM-sleep, and in theta activity (5-9 Hz) during wakefulness may reflect local variations in sleep need induced by recent experience-dependent brain plasticity1. However, such evidence is mainly based on studies involving the sensorimotor domain. Previous attempts to extend these findings to a purely sensory system –such as the visual system– provided contradictory results. To clarify this issue, here we evaluated the effects of short-term visual deprivation on low-frequency EEG activity during wakefulness and sleep.
Materials and Methods: twelve healthy volunteers (25.5±3.7 yrs, 6 M) participated to two experimental sessions (order counterbalanced across participants), each lasting from ~2.30 pm to ~8.30 am of the following day: a visual deprivation (VD) condition, during which subjects were blindfolded, and a visual stimulation (VS) condition. All activities were rigorously regulated: in VD, subjects had to listen to audiobooks for ~6 h, while in VS they watched movies for a similar amount of time. All participants slept for ~7.5 h (11.30 pm – 7.00 am), while their brain activity was recorded using high-density (hd-)EEG (256 electrodes). Brief test sessions including an auditory psychomotor vigilance test (aPVT) and Likert-scales for sleepiness, alertness and mood were completed every 2 h and ~40 min after awakening. Three 2 min eyes closed hd-EEG recordings were obtained before and after sleep to investigate potential variations in local theta power. Mean SWA, slow wave density and amplitude6 were calculated for the first 20 min of NREM-sleep. Statistical analyses (paired t-tests) were restricted to an occipital and a centro-frontal region of interest (ROI).
Results: relative to VS, VD was associated with reduced N1 and REM latency and with increased REM duration and proportion (p < 0.05). No differences were observed in other sleep parameters. No significant differences between VS and VD were observed in aPVT reaction time, subjective sleepiness, alertness and mood either before or after sleep. In eyes-closed wake recordings before sleep, occipital (but not frontal) theta power was higher after VS than after VD (p < 0.03; ~11.00 pm) and this difference disappeared after a night of sleep (p > 0.23; ~8.00 am). During the first 20 min of NREM-sleep, SWA and slow wave amplitude showed no significant differences across experimental condition. However, the density of occipital (but not frontal) slow waves tended to be higher in VS (p = 0.09). Additional analyses showed that small (amplitude < 30 µV), occipital (but not large and/or frontal) slow waves were significantly more numerous after VS than after VD (p < 0.02).
Discussion: short-term visual deprivation is associated with an occipital decrease in theta activity during wakefulness, and in the density of small, local slow waves during NREM-sleep, likely reflecting local, experience-related changes in cortical plasticity. However, in contrast to previous observations involving the sensorimotor domain, sleep SWA and slow wave amplitude showed no clear changes, suggesting that important regional differences may exist with respect to the morphology of slow waves and their relation to experience-dependent modifications.
Giulio Bernardi
Monica Betta
monica.betta@imtlucca.it
Jacinthe Cataldi
Andrea Leo
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
J. Haba-Rubio
Pietro Pietrini
pietro.pietrini@imtlucca.it
R. Heinzer
Francesca Siclari
2017-09-04T15:21:57Z
2017-09-04T15:21:57Z
http://eprints.imtlucca.it/id/eprint/3780
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3780
2017-09-04T15:21:57Z
Quantifying peripheral sympathetic activation during sleep by means of an automatic method for pulse wave amplitude drop detection
Introduction: drops in pulse wave amplitude (PWA) measured by finger photoplethysmography (PPG) are known to reflect peripheral vasoconstriction resulting from sympathetic activation. Quantifying the amount of sympathetic activation during sleep would be useful to investigate the link between sleep disorders, like sleep apnea, and cardio-vascular morbidity-mortality. However, automatic algorithms allowing for a simple and rapid extraction and characterization of PWA parameters are not readily available. Therefore, in the present study we developed and validated a novel automatic approach to detect and characterize PWA-drops in whole-night polysomnographic (PSG) data.
Materials and Methods: PSG recordings of 9 patients (52±5yrs, 7F) from the HypnoLaus Sleep Cohort were analyzed. The PPG signal was smoothed and detrended before extraction of the PWA signal, defined at each cardiac cycle as the difference between the peak and nadir values of the corresponding PPG-waveform. The time-courses of PWA variance and first-derivative were then evaluated using a moving-window over 5 heartbeats. Candidate time-points for potential PWA-drops were defined as local peaks in the PWA-variance showing correspondent first-derivative negative values. For each PWA-drop candidate, an observation interval was delimited between the closest previous and subsequent PWA maxima, and the maximum percent decrease (amplitude) was computed with respect to the mean of the previous 5 PWA values extracted from stable signal tracts (low local variance and duration >2sec). Then, PWA-drops with amplitude >30% and duration >4 heartbeats were identified, and their amplitude (%), descending slope (%/s) and total duration (s) were estimated. The PWA-drop index was calculated as the number of drops per hour. The algorithm detections were compared with those of an expert scorer who marked PWA-drops with amplitudes >30% (3min scoring window).
Results: with respect to the human scorer, the algorithm achieved a sensitivity of 97.4%, a specificity of 89.5%, and a precision of 49.6%. In spite of the apparently low precision, both visual inspection and a direct comparison between false positive (FP) and true positive (TP) detections showed that the algorithm correctly identified above-threshold drops that were missed by the human scorer (minimum amplitude was 32.1±1.5% for FP, and 37.6±3.7% for TP). Only ~31% of all detected PWA-drops were associated with a (visually scored) EEG-arousal, whereas most EEG-arousals (~72%) showed an association with a PWA-drop. Interestingly, among PWA-drops that were not associated with a scored EEG-arousal, 19-55% (depending on sleep stage) were nevertheless accompanied by a strong increase in high-frequency EEG-power, potentially reflecting a cortical activation not visible to the human eye. Finally, the index, amplitude and duration tended to decrease from light (N1) to deep (N3) NREM sleep (p<0.05, rmANOVA), while REM sleep showed a significantly higher PWA-drop index compared to NREM stages (53.5±19.3d/h vs. 42.1±18.7d/h in N1).
Discussion: the automatic algorithm allowed to reliably detect PWA-drops occurring in all sleep stages, including events not recognized upon standard visual inspection. This automatic algorithm may represent a simple and useful tool to quantify the degree of peripheral sympathetic activation during sleep and may provide relevant information about associated ‘cortical activations’ during sleep.
Monica Betta
monica.betta@imtlucca.it
Giulio Bernardi
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
J. Haba-Rubio
Francesca Siclari
R. Heinzer
2017-09-04T14:50:49Z
2017-09-04T14:50:49Z
http://eprints.imtlucca.it/id/eprint/3779
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3779
2017-09-04T14:50:49Z
Regionally specific features of low-frequency EEG oscillations during REM-sleep
Giulio Bernardi
Monica Betta
monica.betta@imtlucca.it
Yu Xiaoqian
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
J. Haba-Rubio
R. Heinzer
Pietro Pietrini
pietro.pietrini@imtlucca.it
Giulio Tononi
Francesca Siclari
2017-08-04T10:23:17Z
2017-08-04T10:23:17Z
http://eprints.imtlucca.it/id/eprint/3746
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3746
2017-08-04T10:23:17Z
Modality-independent encoding of individual concepts in the left parietal cortex
Abstract The organization of semantic information in the brain has been mainly explored through category-based models, on the assumption that categories broadly reflect the organization of conceptual knowledge. However, the analysis of concepts as individual entities, rather than as items belonging to distinct superordinate categories, may represent a significant advancement in the comprehension of how conceptual knowledge is encoded in the human brain. Here, we studied the individual representation of thirty concrete nouns from six different categories, across different sensory modalities (i.e., auditory and visual) and groups (i.e., sighted and congenitally blind individuals) in a core hub of the semantic network, the left angular gyrus, and in its neighboring regions within the lateral parietal cortex. Four models based on either perceptual or semantic features at different levels of complexity (i.e., low- or high-level) were used to predict fMRI brain activity using representational similarity encoding analysis. When controlling for the superordinate component, high-level models based on semantic and shape information led to significant encoding accuracies in the intraparietal sulcus only. This region is involved in feature binding and combination of concepts across multiple sensory modalities, suggesting its role in high-level representation of conceptual knowledge. Moreover, when the information regarding superordinate categories is retained, a large extent of parietal cortex is engaged. This result indicates the need to control for the coarse-level categorial organization when performing studies on higher-level processes related to the retrieval of semantic information.
Giacomo Handjaras
Andrea Leo
Luca Cecchetti
luca.cecchetti@imtlucca.it
Paolo Papale
Alessandro Lenci
Giovanna Marotta
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
2017-06-21T13:17:10Z
2017-06-21T13:17:10Z
http://eprints.imtlucca.it/id/eprint/3714
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3714
2017-06-21T13:17:10Z
In favor of the phonemic principle: a review of neurophysiological and neuroimaging explorations into the neural correlates of phonological competence
In the last thirty years, in vivo brain structural and functional exploration has sparked vivid light on the neural correlates of language. Along these lines, the study of phono- logical competence has offered a ‘neural view’ into the organization of basic speech- sensitive areas, improving the sensitivity of pre-surgical mapping and brain-computer interface-based communication. Nevertheless, only rarely the significance of these results has been recognized in the context of a century-long discussion around the theoretical, physical and cognitive consistency of the phoneme itself. Here we review recent investigations into speech perception, imagery and production at the segmen- tal level through neuroimaging and neurophysiological techniques, showing that phonemes are processed as discrete entities, which are categorized in cognition as unique products of their acoustic and articulatory features, despite the seamless flow of the speech signal. These results seem to expand the scope of the motor theory of speech perception.
Alessandra Cecilia Rampinini
alessandra.rampinini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
2017-04-03T08:56:38Z
2017-04-03T08:56:38Z
http://eprints.imtlucca.it/id/eprint/3682
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3682
2017-04-03T08:56:38Z
Not in one metric: Neuroticism modulates different resting state metrics within distinctive brain regions
Introduction Neuroticism is a complex personality trait encompassing diverse aspects. Notably, high levels of neuroticism are related to the onset of psychiatric conditions, including anxiety and mood disorders. Personality traits are stable individual features; therefore, they can be expected to be associated with stable neurobiological features, including the Brain Resting State (RS) activity as measured by fMRI. Several metrics have been used to describe {RS} properties, yielding rather inconsistent results. This inconsistency could be due to the fact that different metrics portray different {RS} signal properties and that these properties may be differently affected by neuroticism. To explore the distinct effects of neuroticism, we assessed several distinct metrics portraying different {RS} properties within the same population. Method Neuroticism was measured in 31 healthy subjects using the Zuckerman-Kuhlman Personality Questionnaire; {RS} was acquired by high-resolution fMRI. Using linear regression, we examined the modulatory effects of neuroticism on {RS} activity, as quantified by the Amplitude of low frequency fluctuations (ALFF, fALFF), regional homogeneity (REHO), Hurst Exponent (H), global connectivity (GC) and amygdalae functional connectivity. Results Neuroticism modulated the different metrics across a wide network of brain regions, including emotional regulatory, default mode and visual networks. Except for some similarities in key brain regions for emotional expression and regulation, neuroticism affected different metrics in different ways. Discussion Metrics more related to the measurement of regional intrinsic brain activity (fALFF, {ALFF} and REHO), or that provide a parsimonious index of integrated and segregated brain activity (HE), were more broadly modulated in regions related to emotions and their regulation. Metrics related to connectivity were modulated across a wider network of areas. Overall, these results show that neuroticism affects distinct aspects of brain resting state activity. More in general, these findings indicate that a multiparametric approach may be required to obtain a more detailed characterization of the neural underpinnings of a given psychological trait.
Claudio Gentili
Ioana Alina Cristea
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Nicola Vanello
Cristian Popita
Daniel David
Pietro Pietrini
pietro.pietrini@imtlucca.it
2017-03-21T13:49:11Z
2017-09-04T13:34:32Z
http://eprints.imtlucca.it/id/eprint/3678
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3678
2017-03-21T13:49:11Z
Low-frequency oscillations in REM-sleep: a high density
EEG study
Objectives: Slow waves (0.5–4 Hz) of non-rapid eye movement
(NREM) sleep occur and are regulated locally, in an experiencedependent
manner. However, recent work in mice showed that
region-specific slow waves may also occur in REM sleep. Here we
investigated the presence and cortical distribution of low-frequency
oscillations in human REM sleep using high-density EEG.
Giulio Bernardi
Monica Betta
monica.betta@imtlucca.it
X. Yu
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
J. Haba-Rubio
R. Heinzer
Pietro Pietrini
pietro.pietrini@imtlucca.it
Giulio Tononi
Francesca Siclari
2017-03-21T13:32:35Z
2017-08-04T10:14:43Z
http://eprints.imtlucca.it/id/eprint/3677
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3677
2017-03-21T13:32:35Z
Foreground Enhancement and Background Suppression in Human Early Visual System During Passive Perception of Natural Images
One of the major challenges in visual neuroscience is represented by foreground-background segmentation, a process that is supposed to rely on computations in cortical modules, as information progresses from V1 to V4. Data from nonhuman primates (Poort et al., 2016) showed that segmentation leads to two distinct, but associated processes: the enhancement of cortical activity associated to figure processing (i.e., foreground enhancement) and the suppression of ground-related cortical activity (i.e., background suppression). To characterize foreground-background segmentation of natural stimuli in humans, we parametrically modulated low-level properties of 334 images and their behaviorally segmented counterparts. A model based on simple visual features was then adopted to describe the filtered and intact images, and to evaluate their resemblance with fMRI activity in different visual cortices (V1, V2, V3, V3A, V3B, V4, LOC). Results from representational similarity analysis (Kriegeskorte et al., 2008) showed that the correspondence between behaviorally segmented natural images and brain activity increases throughout the visual processing stream. We found evidence of foreground enhancement for all the tested visual regions, while background suppression occurs in V3B, V4 and LOC. Our results suggest that foreground-background segmentation is an automatic process that occurs during natural viewing, and cannot be merely ascribed to differences in objects size or location. Finally, neural images reconstructed from V4 and LOC fMRI activity revealed a preserved spatial resolution of foreground textures, indicating a richer representation of the salient part of natural images, rather than a simplistic model of objects shape.
Paolo Papale
Andrea Leo
Luca Cecchetti
luca.cecchetti@imtlucca.it
Giacomo Handjaras
Kendrick Kay
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
2017-01-09T10:13:36Z
2017-08-04T10:18:34Z
http://eprints.imtlucca.it/id/eprint/3624
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3624
2017-01-09T10:13:36Z
Progression from Vegetative to Minimally Conscious State Is Associated with Changes in Brain Neural Response to Passive Tasks: A Longitudinal Single-Case Functional MRI Study
Objectives: Functional magnetic resonance imaging (fMRI) may be adopted as a complementary tool for bedside observation in the disorders of consciousness (DOC). However, the diagnostic value of this technique is still debated because of the lack of accuracy in determining levels of consciousness within a single patient. Recently, Giacino and colleagues (2014) hypothesized that a longitudinal fMRI evaluation may provide a more informative assessment in the detection of residual awareness. The aim of this study was to measure the correspondence between clinically defined level of awareness and neural responses within a single DOC patient. Methods: We used a follow-up fMRI design in combination with a passive speech-processing task. Patient’s consciousness was measured through time by using the Coma Recovery Scale. Results: The patient progressed from a vegetative state (VS) to a minimally conscious state (MCS). Patient’s task-related neural responses mirrored the clinical change from a VS to an MCS. Specifically, while in an MCS, but not a VS, the patient showed a selective recruitment of the left angular gyrus when he listened to a native speech narrative, as compared to the reverse presentation of the same stimulus. Furthermore, the patient showed an increased response in the language-related brain network and a greater deactivation in the default mode network following his progression to an MCS. Conclusions: Our findings indicate that longitudinal assessment of brain responses to passive stimuli can contribute to the definition of the clinical status in individual patients with DOC and represents an adequate counterpart of the bedside assessment during the diagnostic decision-making process. (JINS, 2016, 22, 620–630)
Francesco Tomaiuolo
Luca Cecchetti
luca.cecchetti@imtlucca.it
Raechelle M. Gibson
Fiammetta Logi
Adrian M. Owen
Franco Malasoma
Sabino Cozza
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
2016-11-28T17:18:28Z
2017-08-04T10:15:38Z
http://eprints.imtlucca.it/id/eprint/3605
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3605
2016-11-28T17:18:28Z
Are Supramodality and Cross-Modal Plasticity the Yin and Yang of Brain Development? From Blindness to Rehabilitation
Research in blind individuals has primarily focused for a long time on the brain plastic reorganization that occurs in early visual areas. Only more recently, scientists have developed innovative strategies to understand to what extent vision is truly a mandatory prerequisite for the brain’s fine morphological architecture to develop and function. As a whole, the studies conducted to date in sighted and congenitally blind individuals have provided ample evidence that several ‘visual’ cortical areas develop independently from visual experience and do process information content regardless of the sensory modality through which a particular stimulus is conveyed: a property named supramodality. At the same time, lack of vision leads to a structural and functional reorganization within 'visual' brain areas, a phenomenon known as cross-modal plasticity. Cross-modal recruitment of the occipital cortex in visually deprived individuals represents an adaptative compensatory mechanism that mediates processing of non-visual inputs. Supramodality and cross-modal plasticity appear to be the 'yin and yang' of brain development: supramodal is what takes place despite the lack of vision, whereas cross-modal is what happens because of lack of vision. Here we provide a critical overview of the research in this field and discuss the implications that these novel findings have for the development of educative/rehabilitation approaches and sensory substitution devices in sensory-impaired individuals.
Luca Cecchetti
luca.cecchetti@imtlucca.it
Ron Kupers
Maurice Ptito
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
2016-11-28T17:15:33Z
2017-08-04T11:53:03Z
http://eprints.imtlucca.it/id/eprint/3604
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3604
2016-11-28T17:15:33Z
When Neuroscience ‘Touches’ Architecture: From Hapticity to a Supramodal Functioning of the Human Brain
In the last decades, the rapid growth of functional brain imaging methodologies allowed cognitive neuroscience to address open questions in philosophy and social sciences. At the same time, novel insights from cognitive neuroscience research have begun to influence various disciplines, leading to a turn to cognition and emotion in the fields of planning and architectural design. Since 2003, the Academy of Neuroscience for Architecture has been supporting ‘neuro-architecture’ as a way to connect neuroscience and the study of behavioral responses to the built environment. Among the many topics related to multisensory perceptual integration and embodiment, the concept of hapticity was recently introduced, suggesting a pivotal role of tactile perception and haptic imagery in architectural appraisal. Arguments have thus risen in favor of the existence of shared cognitive foundations between hapticity and the supramodal functional architecture of the human brain. Precisely, supramodality refers to the functional feature of defined brain regions to process and represent specific information content in a more abstract way, independently of the sensory modality conveying such information to the brain. Here, we highlight some commonalities and differences between the concepts of hapticity and supramodality according to the distinctive perspectives of architecture and cognitive neuroscience. This comparison and connection between these two different approaches may lead to novel observations in regard to people–environment relationships, and even provide empirical foundations for a renewed evidence-based design theory.
Paolo Papale
Leonardo Chiesi
Alessandra Cecilia Rampinini
alessandra.rampinini@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
2016-10-05T13:17:08Z
2017-03-27T11:08:21Z
http://eprints.imtlucca.it/id/eprint/3559
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3559
2016-10-05T13:17:08Z
Hand synergies: Integration of robotics and neuroscience for understanding the control of biological and artificial hands.
The term 'synergy' - from the Greek synergia - means 'working together'. The concept of multiple elements working together towards a common goal has been extensively used in neuroscience to develop theoretical frameworks, experimental approaches, and analytical techniques to understand neural control of movement, and for applications for neuro-rehabilitation. In the past decade, roboticists have successfully applied the framework of synergies to create novel design and control concepts for artificial hands, i.e., robotic hands and prostheses. At the same time, robotic research on the sensorimotor integration underlying the control and sensing of artificial hands has inspired new research approaches in neuroscience, and has provided useful instruments for novel experiments. The ambitious goal of integrating expertise and research approaches in robotics and neuroscience to study the properties and applications of the concept of synergies is generating a number of multidisciplinary cooperative projects, among which the recently finished 4-year European project "The Hand Embodied" (THE). This paper reviews the main insights provided by this framework. Specifically, we provide an overview of neuroscientific bases of hand synergies and introduce how robotics has leveraged the insights from neuroscience for innovative design in hardware and controllers for biomedical engineering applications, including myoelectric hand prostheses, devices for haptics research, and wearable sensing of human hand kinematics. The review also emphasizes how this multidisciplinary collaboration has generated new ways to conceptualize a synergy-based approach for robotics, and provides guidelines and principles for analyzing human behavior and synthesizing artificial robotic systems based on a theory of synergies.
Marco Santello
Matteo Bianchi
Marco Gabiccini
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Gionata Salvietti
Domenico Prattichizzo
Marc Ernst
Alessandro Moscatelli
Henrik Jörntell
Astrid M L Kappers
Kostas Kyriakopoulos
Alin Albu-Schäffer
Claudio Castellini
Antonio Bicchi
2016-10-05T13:15:44Z
2017-06-21T13:18:09Z
http://eprints.imtlucca.it/id/eprint/3558
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3558
2016-10-05T13:15:44Z
When Neuroscience 'Touches' Architecture: From Hapticity to a Supramodal Functioning of the Human Brain.
In the last decades, the rapid growth of functional brain imaging methodologies allowed cognitive neuroscience to address open questions in philosophy and social sciences. At the same time, novel insights from cognitive neuroscience research have begun to influence various disciplines, leading to a turn to cognition and emotion in the fields of planning and architectural design. Since 2003, the Academy of Neuroscience for Architecture has been supporting 'neuro-architecture' as a way to connect neuroscience and the study of behavioral responses to the built environment. Among the many topics related to multisensory perceptual integration and embodiment, the concept of hapticity was recently introduced, suggesting a pivotal role of tactile perception and haptic imagery in architectural appraisal. Arguments have thus risen in favor of the existence of shared cognitive foundations between hapticity and the supramodal functional architecture of the human brain. Precisely, supramodality refers to the functional feature of defined brain regions to process and represent specific information content in a more abstract way, independently of the sensory modality conveying such information to the brain. Here, we highlight some commonalities and differences between the concepts of hapticity and supramodality according to the distinctive perspectives of architecture and cognitive neuroscience. This comparison and connection between these two different approaches may lead to novel observations in regard to people-environment relationships, and even provide empirical foundations for a renewed evidence-based design theory.
Paolo Papale
Leonardo Chiesi
Alessandra Cecilia Rampinini
alessandra.rampinini@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
2016-10-05T13:11:35Z
2017-03-27T11:07:09Z
http://eprints.imtlucca.it/id/eprint/3557
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3557
2016-10-05T13:11:35Z
Towards a synergy framework across neuroscience and robotics: Lessons learned and open questions. Reply to comments on: "Hand synergies: Integration of robotics and neuroscience for understanding the control of biological and artificial hands".
Marco Santello
Matteo Bianchi
Marco Gabiccini
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Gionata Salvietti
Domenico Prattichizzo
Marc Ernst
Alessandro Moscatelli
Henrik Jorntell
Astrid M L Kappers
Kostas Kyriakopoulos
Alin Abu Schaeffer
Claudio Castellini
Antonio Bicchi
2016-09-13T13:50:20Z
2016-09-13T13:50:20Z
http://eprints.imtlucca.it/id/eprint/3539
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3539
2016-09-13T13:50:20Z
Etica nella ricerca psicofarmacologica
Mario Guazzelli
M.L. Monosi
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
2016-09-13T08:20:42Z
2016-09-13T08:20:42Z
http://eprints.imtlucca.it/id/eprint/3538
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3538
2016-09-13T08:20:42Z
Neural correlates of spatial working memory in humans: a functional magnetic resonance imaging study comparing visual and tactile processes
Recent studies of neural correlates of working memory components have identified both low-level perceptual processes and higher-order supramodal mechanisms through which sensory information can be integrated and manipulated. In addition to the primary sensory cortices, working memory relies on a widely distributed neural system of higher-order association areas that includes posterior parietal and occipital areas, and on prefrontal cortex for maintaining and manipulating information. The present study was designed to determine brain patterns of neural response to the same spatial working memory task presented either visually or in a tactile format, and to evaluate the relationship between spatial processing in the visual and tactile sensory modalities. Brain activity during visual and tactile spatial working memory tasks was measured in six young right-handed healthy male volunteers by using functional magnetic resonance imaging. Results indicated that similar fronto-parietal networks were recruited during spatial information processing across the two sensory modalities—specifically the posterior parietal cortex, the dorsolateral prefrontal cortex and the anterior cingulate cortex. These findings provide a neurobiological support to behavioral observations by indicating that common cerebral regions subserve generation of higher order mental representations involved in working memory independently from a specific sensory modality.
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Daniela Bonino
Claudio Gentili
Lorenzo Sani
Pietro Pietrini
pietro.pietrini@imtlucca.it
Tomaso Vecchi
2016-09-13T08:14:47Z
2016-09-13T08:14:47Z
http://eprints.imtlucca.it/id/eprint/3537
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3537
2016-09-13T08:14:47Z
Combination of event-related potentials and functional magnetic resonance imaging during single-letter reading
This work proposes a mathematical approach for combining event-related potentials (ERPs) and functional magnetic resonance images (fMRI). Data were separately recorded during the same event-related experimental design, consisting of visually presented single letters and non-alphabetic symbols, that had to be either simply observed (passive condition) or read aloud (active condition). This protocol was useful for exploring the neural correlates of reading processes. Healthy adults participated in the experiment. Averaged ERPs were decomposed by independent component analysis; low resolution electromagnetic tomography (LORETA) was applied to estimate the current density distribution maps of each independent component. fMRI images time series were analyzed by multiple linear regression. ERP-fMRI correspondence was quantified by computing the Euclidean distance between LORETA local maxima and clusters of significantly activated fMRI voxels. During reading aloud of letters, that is clearly the task most similar to natural reading conditions, significant electrical and hemodynamic response was observed in the left medial frontal gyrus (BA 6) and left middle temporal gyrus (BA 22/39) just before articulation and in the bilateral middle superior temporal gyrus (BA 22/37) during and after verbal-motor production. These results indicate that the middle-superior temporal gyrus plays a crucial and multifunctional role in grapheme-phoneme matching
Silvia Casarotto
Anna M. Bianchi
Sergio Cerutti
Nicola Vanello
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Claudio Gentili
Lorenzo Sani
Daniela Bonino
Mario Guazzelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
Luigi Landini
Giuseppe A. Chiarenza
2016-09-13T07:02:01Z
2016-09-13T07:02:01Z
http://eprints.imtlucca.it/id/eprint/3536
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3536
2016-09-13T07:02:01Z
Neural correlates of extinction of moral pain through forgiveness
Giuseppina Rota
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Lorenzo Sani
Claudio Gentili
Nicola Vanello
Mario Guazzelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-09-12T11:53:14Z
2016-09-13T06:34:44Z
http://eprints.imtlucca.it/id/eprint/3534
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3534
2016-09-12T11:53:14Z
Effects of visual experience on the human MT+ functional connectivity networks: an fMRI study of motion perception in sighted and congenitally blind individuals
Human middle temporal complex (hMT+) responds also to the perception of non-visual motion in both sighted and early blind individuals, indicating a supramodal organization. Visual experience, however, leads to a segregation of hMT+ into a more anterior subregion, involved in the supramodal representation of motion, and a posterior subregion that processes visual motion only. In contrast, in congenitally blind subjects tactile motion activates the full extent of hMT+. Here, we used fMRI to investigate brain areas functionally connected with the two hMT+ subregions (seeds) during visual and tactile motion in sighted and blind individuals. A common functional connectivity network for motion processing, including bilateral ventral and dorsal extrastriate, inferior frontal, middle and inferior temporal areas, correlated with the two hMT+ seeds both in sighted and blind individuals during either visual or tactile motion, independently from the sensory modality through which the information was acquired. Moreover, ventral premotor, somatosensory, and posterior parietal areas correlated only with the anterior but not with the posterior portion of hMT+ in sighted subjects, and with both hMT+ seeds in blind subjects. Furthermore, a correlation between middle temporal and occipital areas with primary somatosensory seeds was demonstrated across conditions in both sighted and blind individuals, suggesting a cortico-cortical pathway that conveys non-visual information from somatosensory cortex, through posterior parietal regions, to ventral extrastriate cortex. These findings expand our knowledge about the development of the functional organization within hMT+ by showing that distinct patterns of brain functional correlations originate from the anterior and posterior hMT+ subregions as a result of visual experience.
Pietro Pietrini
pietro.pietrini@imtlucca.it
James V. Haxby
Nicola Vanello
Claudio Gentili
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Lorenzo Sani
2016-09-12T11:28:13Z
2016-09-12T11:28:13Z
http://eprints.imtlucca.it/id/eprint/3532
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3532
2016-09-12T11:28:13Z
Early dysfunction of perceptual processes in developmental dyslexia
Objective: Single-letter reading is an early predictor of later reading success and identifies adult dyslexics [1]. This work investigates the differences between healthy and dyslexic children in brain activity during single-letter reading.
Methods: Event-related potentials (ERPs) were recorded from 45 healthy and 45 dyslexic children (age range 8–10 years) during self-paced letter recognition (SPLR), i.e. active reading aloud of letters presented at a self-determined pace. Standardized Low Resolution Electromagnetic Tomography (sLORETA) [2] was applied to individual ERPs and unpaired voxel-by-voxel t-test analysis (P < 0.05) was performed to compare the sLORETA maps between groups of subjects corresponding with the latency of the main grand average peaks.
Results: At middle latencies, dyslexics were characterized by a greater activation in the right middle-inferior frontal, insular and superior temporal regions and by impaired engagement of the left middle parietal lobe as compared to the healthy controls. At middle-long latencies, a significantly reduced activation in the left occipital gyrus was observed in dyslexic children compared to controls.
Conclusions: Distributed source imaging applied to ERPs describes the spatiotemporal dynamics of cerebral reading functions and allows inference regarding at which stage of the reading process the activation of the involved brain regions is disrupted in impaired readers. The existence of specific compensatory mechanisms may explain why dyslexic children who are characterized by impaired activation of left parietal and occipital regions show a significantly greater involvement of right temporal–parietal regions and premature engagement of right middle–inferior frontal regions as compared to controls.
Giuseppe A. Chiarenza
Silvia Casarotto
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Lorenzo Sani
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-09-12T11:12:22Z
2016-09-12T11:12:22Z
http://eprints.imtlucca.it/id/eprint/3531
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3531
2016-09-12T11:12:22Z
Analysis of residual dependencies of independent components extracted from fMRI data
Independent component analysis (ICA) of functional magnetic resonance imaging (fMRI) data can be employed as an exploratory method. The lack in the ICA model of strong a priori assumptions about the signal or about the noise leads to difficult interpretations of the results. Moreover, the statistical independence of the components is only approximated. Residual dependencies among the components can reveal informative structure in the data. A major problem is related to model order selection, that is, the number of components to be extracted. Specifically, overestimation may lead to component splitting. In this work, a method based on hierarchical clustering of ICA applied to fMRI datasets is investigated. The clustering algorithm uses a metric based on the mutual information between the ICs. To estimate the similarity measure, a histogram-based technique and one based on kernel density estimation are tested on simulated datasets. Simulations results indicate that the method could be used to cluster components related to the same task and resulting from a splitting process occurring at different model orders. Different performances of the similarity measures were found and discussed. Preliminary results on real data are reported and show that the method can group task related and transiently task related components.
Nicola Vanello
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Luigi Landini
2016-09-12T11:00:16Z
2017-08-04T10:17:42Z
http://eprints.imtlucca.it/id/eprint/3530
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3530
2016-09-12T11:00:16Z
Congenital blindness affects diencephalic but not mesencephalic structures in the human brain
While there is ample evidence that the structure and function of visual cortical areas are affected by early visual deprivation, little is known of how early blindness modifies subcortical relay and association thalamic nuclei, as well as mesencephalic structures. Therefore, in the present multicenter study, we used MRI to measure volume of the superior and inferior colliculi, as well as of the thalamic nuclei relaying sensory and motor information to the neocortex, parcellated according to atlas-based thalamo-cortical connections, in 29 individuals with congenital blindness of peripheral origin (17 M, age 35.7 ± 14.3 years) and 29 sighted subjects (17 M, age 31.9 ± 9.0). Blind participants showed an overall volume reduction in the left (p = 0.008) and right (p = 0.007) thalami, as compared to the sighted individuals. Specifically, the lateral geniculate (i.e., primary visual thalamic relay nucleus) was 40 % reduced (left: p = 4 × 10−6, right: p < 1 × 10−6), consistent with findings from animal studies. In addition, associated thalamic nuclei that project to temporal (left: p = 0.005, right: p = 0.005), prefrontal (left: p = 0.010, right: p = 0.014), occipital (left: p = 0.005, right: p = 0.023), and right premotor (p = 0.024) cortical regions were also significantly reduced in the congenitally blind group. Conversely, volumes of the relay nuclei directly involved in auditory, motor, and somatosensory processing were not affected by visual deprivation. In contrast, no difference in volume was observed in either the superior or the inferior colliculus between the two groups. Our findings indicate that visual loss since birth leads to selective volumetric changes within diencephalic, but not mesencephalic, structures. Both changes in reciprocal cortico-thalamic connections or modifications in the intrinsic connectivity between relay and association nuclei of the thalamus may contribute to explain these alterations in thalamic volumes. Sparing of the superior colliculi is in line with their composite, multisensory projections, and with their not exclusive visual nature.
Luca Cecchetti
luca.cecchetti@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Giacomo Handjaras
Ron Kupers
Maurice Ptito
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-09-12T09:25:16Z
2016-09-12T09:25:16Z
http://eprints.imtlucca.it/id/eprint/3529
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3529
2016-09-12T09:25:16Z
Is social phobia a “mis-communication” disorder? Brain functional connectivity during face perception differs between patients with social phobia and healthy control subjects
Recently, a differential recruitment of brain areas throughout the distributed neural system for face perception has been found in social phobic patients as compared to healthy control subjects. These functional abnormalities in social phobic patients extend beyond emotion-related brain areas, such as the amygdala, to include cortical networks that modulate attention and process other facial features, and they are also associated with an alteration of the task-related activation/deactivation trade-off. Functional connectivity is becoming a powerful tool to examine how components of large-scale distributed neural systems are coupled together while performing a specific function. This study was designed to determine whether functional connectivity networks among brain regions within the distributed system for face perception also would differ between social phobic patients and healthy controls. Data were obtained from eight social phobic patients and seven healthy controls by using functional magnetic resonance imaging. Our findings indicated that social phobic patients and healthy controls have different patterns of functional connectivity across brain regions within both the core and the extended systems for face perception and the default mode network. To our knowledge, this is the first study that shows that functional connectivity during brain response to socially relevant stimuli differs between social phobic patients and healthy controls. These results expand our previous findings and indicate that brain functional changes in social phobic patients are not restricted to a single specific brain structure, but rather involve a mis-communication among different sensory and emotional processing brain areas.
Mario Guazzelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
Maria Ida Gobbini
Claudio Gentili
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Sabrina Danti
2016-06-30T13:04:05Z
2016-09-13T10:10:45Z
http://eprints.imtlucca.it/id/eprint/3495
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3495
2016-06-30T13:04:05Z
Neuronal correlates of cholinergic enhancement on cognitive function: In vivo PET and fMRI studies in humans
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Mario Guazzelli
Maura L. Furey
2016-06-09T10:53:27Z
2016-09-13T10:09:53Z
http://eprints.imtlucca.it/id/eprint/3498
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3498
2016-06-09T10:53:27Z
A Combined ERPs and fMRI Approach to Investigate the Neural Correlates of Reading in the Human Brain
Silvia Casarotto
A.M. Bianchi
Sergio Cerutti
Nicola Vanello
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Claudio Gentili
Lorenzo Sani
Daniela Bonino
Mario Guazzelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
Luigi Landini
Giuseppe A. Chiarenza
2016-06-01T13:05:55Z
2016-09-13T10:07:41Z
http://eprints.imtlucca.it/id/eprint/3496
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3496
2016-06-01T13:05:55Z
Neural correlates of visual and tactile spatial detection in sighted and congenitally-blind subjects
Daniela Bonino
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Lorenzo Sani
Tomaso Vecchi
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-05-11T11:02:48Z
2016-09-13T09:42:41Z
http://eprints.imtlucca.it/id/eprint/3485
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3485
2016-05-11T11:02:48Z
Human and Robot Hands: Sensorimotor Synergies to Bridge the Gap Between Neuroscience and Robotics
The control of the many degrees of freedom of the hand through functional modules (hand synergies) has been proposed as a potentially useful model to describe how the hand can maintain postures while being able to rapidly change its configuration to accomplish a wide range of tasks. However, whether and to what extent synergies are actually encoded in motor cortical areas is still debated. A direct encoding of hand synergies is suggested by electrophysiological studies in nonhuman primates, but the evidence in humans resulted, so far, partial and indirect. In this chapter, we review the organization of the brain network that controls hand posture in humans and present preliminary results of a functional Magnetic Resonance Imaging (fMRI) on the encoding of synergies at a cortical level to control hand posture in humans.
Andrea Leo
Giacomo Handjaras
Hamal Marino
Matteo Bianchi
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
2016-05-10T10:12:52Z
2017-08-04T10:18:13Z
http://eprints.imtlucca.it/id/eprint/3483
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3483
2016-05-10T10:12:52Z
How concepts are encoded in the human brain: A modality independent, category-based cortical organization of semantic knowledge
Abstract How conceptual knowledge is represented in the human brain remains to be determined. To address the differential role of low-level sensory-based and high-level abstract features in semantic processing, we combined behavioral studies of linguistic production and brain activity measures by functional magnetic resonance imaging in sighted and congenitally blind individuals while they performed a property-generation task with concrete nouns from eight categories, presented through visual and/or auditory modalities. Patterns of neural activity within a large semantic cortical network that comprised parahippocampal, lateral occipital, temporo-parieto-occipital and inferior parietal cortices correlated with linguistic production and were independent both from the modality of stimulus presentation (either visual or auditory) and the (lack of) visual experience. In contrast, selected modality-dependent differences were observed only when the analysis was limited to the individual regions within the semantic cortical network. We conclude that conceptual knowledge in the human brain relies on a distributed, modality-independent cortical representation that integrates the partial category and modality specific information retained at a regional level.
Giacomo Handjaras
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Andrea Leo
Alessandro Lenci
Luca Cecchetti
luca.cecchetti@imtlucca.it
Mirco Cosottini
Giovanna Marotta
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-05-04T16:16:35Z
2016-09-13T10:10:31Z
http://eprints.imtlucca.it/id/eprint/3479
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3479
2016-05-04T16:16:35Z
A compatible electrocutaneous display for functional magnetic resonance imaging application
In this paper we propose an MR (magnetic resonance) compatible electrocutaneous stimulator able to inject an electric current, variable in amplitude and frequency, into the fingertips in order to elicit tactile skin receptors (mechanoreceptors). The desired goal is to evoke specific tactile sensations selectively stimulating skin receptors by means of an electric current in place of mechanical stimuli. The field of application ranges from functional magnetic resonance imaging (fMRI) tactile studies to augmented reality technology. The device here proposed is designed using safety criteria in order to comply with the threshold of voltage and current permitted by regulations. Moreover, MR safety and compatibility criteria were considered in order to perform experiments inside the MR scanner during an fMRI acquisition for functional brain activation analysis. Psychophysical laboratory tests are performed in order to define the different evoked tactile sensation. After verifying the device MR safety and compatibility on a phantom, a test on a human subject during fMRI acquisition is performed to visualize the brain areas activated by the simulated tactile sensation.
Valentina Hartwig
Claudia Cappelli
Nicola Vanello
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Enzo Pasquale Scilingo
Giulio Giovannetti
Maria Filomena Santarelli
Vincenzo Positano
Pietro Pietrini
pietro.pietrini@imtlucca.it
Luigi Landini
Antonio Bicchi
2016-04-13T09:01:13Z
2016-09-13T10:20:44Z
http://eprints.imtlucca.it/id/eprint/3438
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3438
2016-04-13T09:01:13Z
Correlation of regional cerebral blood flow and glucose metabolism during rest and audiovisual stimulation in young and older subjects assessed by positron emission tomography
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Gene E. Alexander
Maura L. Furey
G. Giovacchini
Mario Guazzelli
Giovanni Ronca
2016-04-13T08:11:52Z
2016-09-13T10:20:58Z
http://eprints.imtlucca.it/id/eprint/3434
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3434
2016-04-13T08:11:52Z
Coupling between regional cerebral glucose metabolism and blood flow at rest in young and older healthy subjects
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Gene E. Alexander
Maura L. Furey
G. Giovacchini
Barry Horwitz
Alessio Dani
Mario Guazzelli
Stanley I. Rapoport
Mark B. Schapiro
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-04-12T13:02:12Z
2016-09-13T10:20:32Z
http://eprints.imtlucca.it/id/eprint/3432
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3432
2016-04-12T13:02:12Z
Audiovisual stimulation (AS) reveals brain metabolic decline in healthy aging
G. Giovacchini
Gene E. Alexander
Maura L. Furey
Barry Horwitz
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
G. Solaini
Mario Guazzelli
Stanley I. Rapoport
Mark B. Schapiro
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-04-12T09:21:24Z
2016-09-13T10:21:13Z
http://eprints.imtlucca.it/id/eprint/3421
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3421
2016-04-12T09:21:24Z
Effects of healthy aging on the brain functional response to cholinergic enhancement during a visual working memory task in humans
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
Ulderico Freo
Maura L. Furey
2016-04-07T09:54:43Z
2016-09-13T10:20:16Z
http://eprints.imtlucca.it/id/eprint/3397
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3397
2016-04-07T09:54:43Z
Basi neurometaboliche degli effetti della modulazione colinergica: studi PET e fMRI nell'uomo
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Mario Guazzelli
Maura L. Furey
2016-04-07T09:35:27Z
2016-09-13T10:19:50Z
http://eprints.imtlucca.it/id/eprint/3394
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3394
2016-04-07T09:35:27Z
Basi neuronali degli effetti della modulazione farmacologica del sistema colinergico: studi PET e FMRI nell'uomo
Maura L. Furey
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Mario Guazzelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-04-07T08:13:30Z
2016-09-13T10:20:04Z
http://eprints.imtlucca.it/id/eprint/3385
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3385
2016-04-07T08:13:30Z
Correlati neurometabolici del decadimento cognitivo nella malattia di Alzheimer: implicazioni per la terapia
Mario Guazzelli
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-04-06T12:55:25Z
2016-09-13T10:19:13Z
http://eprints.imtlucca.it/id/eprint/3380
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3380
2016-04-06T12:55:25Z
Neural Activity in Ventral Extrastriate Cortex during Tactile
Discrimination of Faces and Other Objects in Congenitally Blind and
Sighted Subjects
Pietro Pietrini
pietro.pietrini@imtlucca.it
Maura L. Furey
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Maria Ida Gobbini
W.-H. Carolyn Wu
Leonardo Cohen
Mario Guazzelli
James V. Haxby
2016-04-06T12:37:18Z
2016-09-13T10:19:35Z
http://eprints.imtlucca.it/id/eprint/3379
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3379
2016-04-06T12:37:18Z
Nuove metodologie per lo studio del cervello
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Maura L. Furey
Mario Guazzelli
Erica Panicucci
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-04-06T12:13:52Z
2016-09-13T10:18:31Z
http://eprints.imtlucca.it/id/eprint/3377
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3377
2016-04-06T12:13:52Z
Seeing with one's hands: Supramodal cortical organization of perception in the human brain revealed by fMRI
Pietro Pietrini
pietro.pietrini@imtlucca.it
Maura L. Furey
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Maria Ida Gobbini
Mario Guazzelli
James V. Haxby
2016-04-05T10:24:52Z
2016-09-13T10:15:35Z
http://eprints.imtlucca.it/id/eprint/3374
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3374
2016-04-05T10:24:52Z
Beyond sensory images: Object-based representation in the human ventral pathway
We investigated whether the topographically organized, category-related patterns of neural response in the ventral visual pathway are a representation of sensory images or a more abstract representation of object form that is not dependent on sensory modality. We used functional MRI to measure patterns of response evoked during visual and tactile recognition of faces and manmade objects in sighted subjects and during tactile recognition in blind subjects. Results showed that visual and tactile recognition evoked category-related patterns of response in a ventral extrastriate visual area in the inferior temporal gyrus that were correlated across modality for manmade objects. Blind subjects also demonstrated category-related patterns of response in this “visual” area, and in more ventral cortical regions in the fusiform gyrus, indicating that these patterns are not due to visual imagery and, furthermore, that visual experience is not necessary for category-related representations to develop in these cortices. These results demonstrate that the representation of objects in the ventral visual pathway is not simply a representation of visual images but, rather, is a representation of more abstract features of object form.
Pietro Pietrini
pietro.pietrini@imtlucca.it
Maura L. Furey
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Maria Ida Gobbini
W.-H. Carolyn Wu
Leonardo Cohen
Mario Guazzelli
James V. Haxby
2016-04-05T09:57:58Z
2016-09-13T10:17:50Z
http://eprints.imtlucca.it/id/eprint/3372
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3372
2016-04-05T09:57:58Z
Perception of optic and tactile flow both activate V5/MT cortical complex in the human brain
V5/MT complex responds selectively to perception of optic flow (Morrone et al., Nature Neurosci , 2001). Since similarities exist between visual and tactile perception, we hypothesized that tactile flow might also rely on V5/MT response. We and others have shown recently that visual extrastriate cortical areas respond both during visual and tactile recognition of objects, indicating that these regions are organized in a supramodal fashion. In this study, we measured neural response evoked during visual and tactile perception of coherently moving dot patterns to test the hypothesis that V5/MT may be supramodally organized and may respond also to tactile stimulation.
Nicola Vanello
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Davide Dente
Nicola Sgambelluri
Enzo Pasquale Scilingo
Claudio Gentili
Lorenzo Sani
Vincenzo Positano
Maria Filomena Santarelli
Mario Guazzelli
James V. Haxby
Luigi Landini
Antonio Bicchi
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-04-05T09:48:25Z
2016-09-13T10:17:30Z
http://eprints.imtlucca.it/id/eprint/3371
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3371
2016-04-05T09:48:25Z
A simulator for multilevel analysis of functional magnetic resonance data
Nicola Vanello
Vincenzo Positano
Maria Filomena Santarelli
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
Luigi Landini
2016-04-05T09:35:29Z
2016-09-13T10:17:03Z
http://eprints.imtlucca.it/id/eprint/3370
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3370
2016-04-05T09:35:29Z
Verso la comprensione delle differenze di genere
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Claudio Gentili
N. Watson
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-04-05T09:14:44Z
2016-09-13T10:16:48Z
http://eprints.imtlucca.it/id/eprint/3369
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3369
2016-04-05T09:14:44Z
Brain activity associated with forgiving and unforgiving behavior in Humans as assessed with fMRI
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Claudio Gentili
M. Rizzo
Nicola Vanello
Lorenzo Sani
Luigi Landini
Mario Guazzelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-04-05T08:50:04Z
2016-09-13T10:15:19Z
http://eprints.imtlucca.it/id/eprint/3368
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3368
2016-04-05T08:50:04Z
A compatibility test for tactile displays designed for
fMRI studies
The purpose of this document is to provide a compatibility test for
mechatronic devices to be used within a diagnostic MR environment. In order
to design new devices that can produce tactile stimuli of different nature inside
the MRI environment, compatibility tests with several materials and mechatronic
devices are reported. Results of these experiments are analyzed in order
to evaluate artefacts caused by the presence and actuation of the devices.
Valentina Hartwig
Nicola Vanello
Roger Gassert
Dominique Chapuis
Maria Filomena Santarelli
Vincenzo Positano
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
Luigi Landini
Antonio Bicchi
2016-04-05T08:38:11Z
2016-09-13T10:16:36Z
http://eprints.imtlucca.it/id/eprint/3367
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3367
2016-04-05T08:38:11Z
Tactile processing of different object categories involves extrastriate visual cortical areas in the human brain
Functional magnetic resonance imaging (fMRI) studies demonstrated
that tactile discrimination evokes patterns of neural response in the extrastriate
ventral temporal cortical areas similar to those induced by the visual percept of
the same category of objects. These findings strongly indicate that object
representation in the ventral visual pathway is not simply a representation of
visual images but quite a representation of more abstract features of object
form.
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Maura L. Furey
Maria Ida Gobbini
Mario Guazzelli
James V. Haxby
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-04-04T10:18:59Z
2016-09-13T10:17:16Z
http://eprints.imtlucca.it/id/eprint/3357
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3357
2016-04-04T10:18:59Z
Perception of visual and tactile flow activates common cortical areas in the human brain
We report results of a pilot study using functional magnetic resonance
imaging aimed at determining the neural correlates of tactile flow. We
hypothesized that brain response to tactile flow would involve the same cortical
areas (V5/MT) that respond to optic flow. Our results showed that V5/MT cortex
indeed is activated by tactile flow perception. These findings are consistent
with a supramodal organization of brain regions involved in optic and tactile
flow processing
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Nicola Vanello
Davide Dente
Nicola Sgambelluri
Enzo Pasquale Scilingo
Claudio Gentili
Lorenzo Sani
Vincenzo Positano
Maria Filomena Santarelli
Mario Guazzelli
James V. Haxby
Luigi Landini
Antonio Bicchi
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-04-04T09:56:50Z
2016-09-13T10:16:09Z
http://eprints.imtlucca.it/id/eprint/3355
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3355
2016-04-04T09:56:50Z
How the brain responds to hurtful events: neural activity elicited by aggressive versus forgiving behavior in humans
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Claudio Gentili
Nicola Vanello
Lorenzo Sani
Mario Guazzelli
2016-04-04T09:49:45Z
2016-09-13T10:16:22Z
http://eprints.imtlucca.it/id/eprint/3354
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3354
2016-04-04T09:49:45Z
Supramodal, topographic and category-related organization in the ventral visual pathway
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Maura L. Furey
Maria Ida Gobbini
Mario Guazzelli
James V. Haxby
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-04-04T09:39:12Z
2016-09-13T10:15:56Z
http://eprints.imtlucca.it/id/eprint/3353
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3353
2016-04-04T09:39:12Z
Cholinergic enhancement during working memory improves information processing in the human brain: effects of age and task difficulty
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Maura L. Furey
2016-03-23T13:12:34Z
2016-09-13T10:18:44Z
http://eprints.imtlucca.it/id/eprint/3321
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3321
2016-03-23T13:12:34Z
Effect of healthy aging on the cholinergic modulation of the interaction between prefrontal cortex (PFC) activity and visual working memory (vWM) task difficulty
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
Stanley I. Rapoport
Mark B. Schapiro
Maura L. Furey
2016-03-23T13:07:11Z
2016-09-13T10:18:01Z
http://eprints.imtlucca.it/id/eprint/3320
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3320
2016-03-23T13:07:11Z
Independent component analysis of fMRI data: a model based approach for artifacts separation
Independent component analysis applied to functional magnetic resonance imaging is a promising technique for non invasive study of brain function. We examine the behavior of spatial ICA decomposition applying ICA to simulated data sets. We study the ICA performances in presence of movement correlated and uncorrelated with activation task, also taking into account the presence of rician distributed noise. We show that the presence of image artifacts due to simulated subject movement and MRI noise greatly affects the method ability to reveal the activation, especially in the presence of movement correlated with activation task. Spatial smoothing of data, before ICA, seems to overcome this problem, allowing us to retrieve the original sources also in the presence of both correlated movement and high noise level.
Nicola Vanello
Vincenzo Positano
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Maria Filomena Santarelli
Mario Guazzelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
Luigi Landini
2016-03-23T13:01:40Z
2016-09-13T10:19:00Z
http://eprints.imtlucca.it/id/eprint/3319
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3319
2016-03-23T13:01:40Z
Separation of movement and task related fMRI signal changes in a simulated data set by Independent Component Analysis
Nicola Vanello
Vincenzo Positano
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Maria Filomena Santarelli
Mario Guazzelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
Luigi Landini
2016-03-23T13:00:07Z
2016-09-13T10:18:13Z
http://eprints.imtlucca.it/id/eprint/3318
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3318
2016-03-23T13:00:07Z
Cholinergic Enhancement during Working Memory Eliminates Regional Cerebral Blood Flow (rCBF) Modulation Associated with Task Difficulty in Prefrontal Cortex
Maura L. Furey
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Stanley I. Rapoport
Mark B. Schapiro
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-03-23T12:27:26Z
2016-09-13T10:13:21Z
http://eprints.imtlucca.it/id/eprint/3314
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3314
2016-03-23T12:27:26Z
Pharmacological Modulation of Prefrontal Cortical Activity During a Working Memory Task in Young and Older Humans: A PET Study With Physostigmine
OBJECTIVE: Age-associated cholinergic dysfunction may contribute to the cognitive decline observed during aging, including a decline in working memory. The current study was designed to determine how healthy aging influences the neural response to working memory before and during pharmacological potentiation of the cholinergic system. METHOD: In 13 young and 13 older healthy volunteers, regional cerebral blood flow (rCBF) was measured by using [15O]H2O and positron emission tomography across 10 scans that alternated between a working-memory-for-faces task and rest. In all subjects, the first two scans were obtained during intravenous saline infusion. Seven young and eight older subjects then received intravenous infusion of physostigmine, a cholinesterase inhibitor, and the remaining six young and five older subjects continued to receive saline. RESULTS: In the placebo condition, task-specific rCBF increases in prefrontal regions were observed in the right middle and inferior frontal cortices in young subjects and in more anterior and ventral prefrontal regions in older individuals. Physostigmine during the working memory task significantly improved performance in both age groups. The right prefrontal regions that were selectively recruited in each age group during the placebo condition showed significantly lower rCBF during physostigmine administration. CONCLUSIONS: Cholinergic enhancement does not affect structurally defined cortical regions but rather modulates neural activity in functionally defined regions, that is, in task-related prefrontal cortical areas that are selectively and distinctively recruited in young and older subjects.
Ulderico Freo
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
Mark B. Schapiro
Stanley I. Rapoport
Maura L. Furey
2016-03-23T12:04:49Z
2016-09-13T10:11:38Z
http://eprints.imtlucca.it/id/eprint/3311
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3311
2016-03-23T12:04:49Z
Study of Reading Processes with ERPs and ER-FMRI
Silvia Casarotto
A.M. Bianchi
Sergio Cerutti
Daniela Bonino
Claudio Gentili
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Lorenzo Sani
Nicola Vanello
Mario Guazzelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
Luigi Landini
Giuseppe A. Chiarenza
2016-03-23T11:57:59Z
2016-09-13T10:14:13Z
http://eprints.imtlucca.it/id/eprint/3310
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3310
2016-03-23T11:57:59Z
Visual and tactile spatial discrimination activates the dorsal cortical pathway: a fMRI study in sighted and congenitally blind humans
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Daniela Bonino
Lorenzo Sani
Claudio Gentili
Nicola Vanello
Luigi Landini
Mario Guazzelli
Tomaso Vecchi
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-03-23T10:54:48Z
2016-09-13T10:14:50Z
http://eprints.imtlucca.it/id/eprint/3309
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3309
2016-03-23T10:54:48Z
Supramodal organization in the "visual" cortical pathways as assessed by functional magnetic resonance in humans
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Nicola Vanello
Daniela Bonino
Claudio Gentili
Lorenzo Sani
Sabrina Danti
Nicola Sgambelluri
James V. Haxby
Luigi Landini
Tomaso Vecchi
Mario Guazzelli
Antonio Bicchi
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-03-23T10:46:51Z
2016-09-13T10:13:48Z
http://eprints.imtlucca.it/id/eprint/3308
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3308
2016-03-23T10:46:51Z
Facial expression representation in the superior temporal sulcus and in fusiform gyrus: an fMRI study
Maria Ida Gobbini
Claudio Gentili
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Nicola Vanello
Mario Guazzelli
James V. Haxby
2016-03-23T10:44:12Z
2016-09-13T10:15:02Z
http://eprints.imtlucca.it/id/eprint/3307
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3307
2016-03-23T10:44:12Z
Optic and tactile flow: does a supramodal response exist?
It is widely accepted [Morrone et al. Nature Neuroscience, 2000] that particular cortical areas like MT/V5 respond to optic flow stimuli. In order to test the hypothesis that the MT+ complex might also share a supramodal organization, we measured the neural response evoked during visual and tactile perception of coherently moving dot patterns (optic and tactile flows) in sighted and blind subjects by using functional magnetic resonance imaging. In particular a group of volunteers were asked to see and touch, during distinct trials, random distribution of dot patterns while moving in circular and translational direction. An ad hoc designed device made of nonmagnetic material was used. Both tactile and visual motion perception consistently activated MT+. In order to exclude the hypothesis that activation in visual cortical areas during tactile discrimination tasks might be attributed merely to visual imagery, tactile stimuli were presented to blind adults, confirming the activation of MT+ complex as well. Moreover, in order to assess the conjecture of supramodality of flow a magneto-compatible haptic display based on the contact area spread rate paradigm (specific aspect of tactile flow) was realized and used in fMRI experiment for investigating the neural activity elicited by tactile flow, providing satisfactory results.
Enzo Pasquale Scilingo
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
Antonio Bicchi
2016-03-23T10:34:11Z
2016-09-13T10:14:39Z
http://eprints.imtlucca.it/id/eprint/3306
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3306
2016-03-23T10:34:11Z
Supramodal response of human MT+ complex to visual and tactile perception of flow as demonstrated by fMRI studies in sighted and congenitally blind individuals
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Lorenzo Sani
Claudio Gentili
Nicola Vanello
James V. Haxby
Luigi Landini
Antonio Bicchi
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-03-23T10:19:49Z
2016-09-13T10:13:35Z
http://eprints.imtlucca.it/id/eprint/3305
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3305
2016-03-23T10:19:49Z
Neural correlates of working memory during visual and tactile spatial discrimination in sighted and congenitally-blind subjects
Claudio Gentili
Daniela Bonino
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Lorenzo Sani
Mario Guazzelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
Tomaso Vecchi
2016-03-23T10:17:52Z
2016-09-13T10:11:22Z
http://eprints.imtlucca.it/id/eprint/3304
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3304
2016-03-23T10:17:52Z
Supramodal cortical organization of the dorsal stream during visual and tactile spatial discrimination in sighted and congenitally-blind subjects
Daniela Bonino
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Lorenzo Sani
Claudio Gentili
Luigi Landini
Mario Guazzelli
Tomaso Vecchi
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-03-23T10:11:37Z
2016-09-13T10:14:28Z
http://eprints.imtlucca.it/id/eprint/3303
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3303
2016-03-23T10:11:37Z
Supramodal organization in the visual cortical pathways in sighted and blind individuals
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Claudio Gentili
Nicola Vanello
Lorenzo Sani
Mario Guazzelli
Luigi Landini
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-03-01T10:32:04Z
2016-09-12T08:28:51Z
http://eprints.imtlucca.it/id/eprint/3170
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3170
2016-03-01T10:32:04Z
A synergy-based hand control is encoded in human motor cortical areas
How the human brain controls hand movements to carry out different tasks is still debated. The concept of synergy has been proposed to indicate functional modules that may simplify the control of hand postures by simultaneously recruiting sets of muscles and joints. However, whether and to what extent synergic hand postures are encoded as such at a cortical level remains unknown. Here, we combined kinematic, electromyography, and brain activity measures obtained by functional magnetic resonance imaging while subjects performed a variety of movements towards virtual objects. Hand postural information, encoded through kinematic synergies, were represented in cortical areas devoted to hand motor control and successfully discriminated individual grasping movements, significantly outperforming alternative somatotopic or muscle-based models. Importantly, hand postural synergies were predicted by neural activation patterns within primary motor cortex. These findings support a novel cortical organization for hand movement control and open potential applications for brain-computer interfaces and neuroprostheses.
Andrea Leo
Giacomo Handjaras
Matteo Bianchi
Hamal Marino
Marco Gabiccini
Andrea Guidi
Enzo Pasquale Scilingo
Pietro Pietrini
pietro.pietrini@imtlucca.it
Antonio Bicchi
Marco Santello
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
2016-02-29T16:53:08Z
2016-09-13T10:11:00Z
http://eprints.imtlucca.it/id/eprint/3169
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3169
2016-02-29T16:53:08Z
Advanced data analysis in brain functional studies with magnetic resonance imaging
Nicola Vanello
Maria Filomena Santarelli
Vincenzo Positano
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
Luigi Landini
2016-02-29T12:03:35Z
2016-09-13T10:11:11Z
http://eprints.imtlucca.it/id/eprint/3167
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3167
2016-02-29T12:03:35Z
Empathy modulates mirror system recruitment in
sighted and congenitally blind individuals
Daniela Bonino
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Mario Guazzelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-02-29T12:01:07Z
2016-09-13T10:13:03Z
http://eprints.imtlucca.it/id/eprint/3166
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3166
2016-02-29T12:01:07Z
Brain correlates of functional and dysfunctional
beliefs: an fmrI study of cognitive reappraisal
Ioana Cristea
Claudio Gentili
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Giuseppina Rota
Daniela Bonino
Daniel David
Pietro Pietrini
pietro.pietrini@imtlucca.it
Mario Guazzelli
2016-02-29T11:43:18Z
2016-09-13T10:13:58Z
http://eprints.imtlucca.it/id/eprint/3165
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3165
2016-02-29T11:43:18Z
What have we learned about seeing from the blind?
A. Pascual-Leone
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
K. Sathian
B. Roeder
A. Amedi
M. Lassonde
L. Merabet
2016-02-29T11:19:00Z
2016-09-13T10:09:38Z
http://eprints.imtlucca.it/id/eprint/3164
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3164
2016-02-29T11:19:00Z
The role of imagery in visual and tactile spatial discrimination in congenitally blind and sighted individuals
Daniela Bonino
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Claudio Gentili
Lorenzo Sani
Mario Guazzelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
Tomaso Vecchi
2016-02-29T10:11:17Z
2016-09-13T10:09:03Z
http://eprints.imtlucca.it/id/eprint/3162
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3162
2016-02-29T10:11:17Z
The Effect of Visual Experience on the Development of Functional Architecture in hMT+
We investigated whether the visual hMT+ cortex plays a role in supramodal representation of sensory flow, not mediated by visual mental imagery. We used functional magnetic resonance imaging to measure neural activity in sighted and congenitally blind individuals during passive perception of optic and tactile flows. Visual motion–responsive cortex, including hMT+, was identified in the lateral occipital and inferior temporal cortices of the sighted subjects by response to optic flow. Tactile flow perception in sighted subjects activated the more anterior part of these cortical regions but deactivated the more posterior part. By contrast, perception of tactile flow in blind subjects activated the full extent, including the more posterior part. These results demonstrate that activation of hMT+ and surrounding cortex by tactile flow is not mediated by visual mental imagery and that the functional organization of hMT+ can develop to subserve tactile flow perception in the absence of any visual experience. Moreover, visual experience leads to a segregation of the motion-responsive occipitotemporal cortex into an anterior subregion involved in the representation of both optic and tactile flows and a posterior subregion that processes optic flow only.
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Nicola Vanello
Lorenzo Sani
Claudio Gentili
Enzo Pasquale Scilingo
Luigi Landini
Mario Guazzelli
Antonio Bicchi
James V. Haxby
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-02-29T09:59:32Z
2016-09-13T10:09:17Z
http://eprints.imtlucca.it/id/eprint/3160
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3160
2016-02-29T09:59:32Z
An MRI Compatibility Study of a Fabric Sensing Glove for Sensory-Motor Brain Activity Exploration
In this work we investigated the compatibility with
functional Magnetic Resonance Imaging (fMRI) studies of a
fabric sensing glove. The glove is able to monitor hand
posture and gesture, and could be fruitfully used in fMRI
studies to explore brain activity during specific tactile or
motor tasks. A specific compatibility test was performed and
results are discussed. Preliminary results of an fMRI
experiment on a subject wearing the glove are also reported
and reproducibility issues are suitably addressed.
Nicola Vanello
Valentina Hartwig
Mario Tesconi
Giuseppe Zupone
Nicola Sgambelluri
Alessandro Tognetti
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Enzo Pasquale Scilingo
Antonio Bicchi
Pietro Pietrini
pietro.pietrini@imtlucca.it
Danilo De Rossi
Luigi Landini
2016-02-29T09:53:52Z
2016-09-13T10:08:24Z
http://eprints.imtlucca.it/id/eprint/3158
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3158
2016-02-29T09:53:52Z
Electrocutaneous stimulation of skin mechanoreceptors for tactile studies with functional Magnetic Resonance Imaging
Valentina Hartwig
Claudia Cappelli
Nicola Vanello
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Enzo Pasquale Scilingo
Giulio Giovannetti
Maria Filomena Santarelli
Vincenzo Positano
Antonio Bicchi
Pietro Pietrini
pietro.pietrini@imtlucca.it
Luigi Landini
2016-02-29T09:33:52Z
2016-09-13T10:07:24Z
http://eprints.imtlucca.it/id/eprint/3156
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3156
2016-02-29T09:33:52Z
Neural correlates of mental representation of space in sighted and congenitally blind individuals as measured by fMRI
Daniela Bonino
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Lorenzo Sani
Tomaso Vecchi
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-02-29T09:32:17Z
2016-09-13T10:08:02Z
http://eprints.imtlucca.it/id/eprint/3155
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3155
2016-02-29T09:32:17Z
ERPs disclose the specificity of spatio-temporal patterns of brain activity during self-paced reading aloud
Silvia Casarotto
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Lorenzo Sani
Mario Guazzelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
Giuseppe A. Chiarenza
2016-02-29T09:29:43Z
2016-09-13T10:08:51Z
http://eprints.imtlucca.it/id/eprint/3154
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3154
2016-02-29T09:29:43Z
Covert visual brand recognition modulates emotional neural networks: a fMRI study
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Silvia Casarotto
F. Sanna
Matteo Corciolani
S. Romani
Daniele Dalli
2016-02-29T09:19:25Z
2016-09-13T10:08:12Z
http://eprints.imtlucca.it/id/eprint/3153
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3153
2016-02-29T09:19:25Z
Single-letter reading elicits a different spatio-temporal modulation of brain activity in dyslexic children as compared to healthy controls
Silvia Casarotto
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Lorenzo Sani
Mario Guazzelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
Giuseppe A. Chiarenza
2016-02-26T09:27:49Z
2016-09-13T10:10:06Z
http://eprints.imtlucca.it/id/eprint/3117
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3117
2016-02-26T09:27:49Z
Physiological reading processes by integrating ERP and fMRI data.
This study investigates the neural correlates of reading by combining ERPs and fMRI. Data were recorded in separate sessions from 8 healthy adults during the same event-related design with jittered inter-stimulus interval. Two passive tasks (letter presentation - LP and symbol presentation - SP) and a reading aloud task (letter recognition - LR) were implemented. Averaged ERPs were decomposed by Independent Component Analysis after data dimensionality reduction by Principal Component Analysis. The independent components (ICs) were associated to well-known physiological potentials: N2_P2b and P2a for all tasks and a late wide negativity (LNA) for LP and LR. Low Resolution Electromagnetic Tomography (LORETA) was applied to single ICs. fMRI data were analysed by multiple linear regression. ERPs-fMRI correspondence was described by the Euclidean distance between LORETA and fMRI local maxima.
Silvia Casarotto
A.M. Bianchi
Giuseppe A. Chiarenza
Nicola Vanello
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-02-22T11:19:25Z
2016-09-13T09:59:34Z
http://eprints.imtlucca.it/id/eprint/3107
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3107
2016-02-22T11:19:25Z
Le basi neurologiche del rapporto tra il consumatore e la marca. Il contributo del neuro-imaging alle ricerche di marketing
Consumer develop very tight relationships with brands. In many cases, consumers develop
positive relationships with their preferred brands and goods. In some of these cases true
“love” relationship may occur. Sometimes, also negative relationships arise, often as a
reaction toward unsatisfactory experiences, bad practices, etc.
Companies aim at developing strong and positive emotional relationships between their
brands and their customers. When they succeed, the brand is immediately recognized, it elicits
positive affective responses, it is more difficult to be substituted for by competitors.
The aim of the present study is to measure behavioral and emotional brain responses to covert
visual recognition of brands. Functional magnetic resonance imaging (fMRI) was used to
measure brain activity in 15 healthy subjects (7 females, 23-33 years) that were exposed to
four stimulus types: coloured scrambled pictures, coloured squares, brand logos, and IAPS
pictures with positive and negative valence scores. Sixty-three popular brands were selected
among 8 different product categories.
Two specific patterns of activation emerged for like (amygdale) and dislike brands (anterior
medial cingulate, left inferior frontal gyrus, left middle temporal gyrus, medial cuneus).
Implications for interpreting the role of brands in consumer mental processes are given, with
special reference to the asymmetry between positive and negative evaluations.
Daniele Dalli
Matteo Corciolani
F. Sanna
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Silvia Casarotto
S. Romani
2016-02-22T11:11:21Z
2016-09-13T09:57:42Z
http://eprints.imtlucca.it/id/eprint/3106
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3106
2016-02-22T11:11:21Z
Is visual experience necessary for the functional development of the mirror neuron system? An fMRI study in sighted and congenitally blind individuals
Daniela Bonino
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Lorenzo Sani
Tomaso Vecchi
Mario Guazzelli
James V. Haxby
Luciano Fadiga
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-02-22T11:06:25Z
2016-09-13T10:01:54Z
http://eprints.imtlucca.it/id/eprint/3105
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3105
2016-02-22T11:06:25Z
Functional Exploration Studies of Supramodal Organization in the Human Extrastriate Cortex
In the context of the Touch-Hapsys project, our group investigated whether the two main components of the cortical visual systems, i.e., the ventral ”what” pathway and the dorsal ”where” pathways, are devoted merely to the processing of visual information or rather they are organized in a supramodal fashion, that is, they are able to process information independently from the sensory modality through which such an information reaches the brain. Sighted and congenitally blind individuals underwent fMRI scan examinations while performing distinct visual and/or tactile experimental tasks involving object recognition, movement detection and spatial localization. These functional studies revealed that both sighted subjects and individuals with no previous visual experience rely on these supramodal brain areas of the ventral and dorsal extrastriate cortex to acquire normal knowledge about objects and interact effectively with the surrounding world.
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Daniela Bonino
Lorenzo Sani
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-02-22T10:57:37Z
2016-09-13T10:02:41Z
http://eprints.imtlucca.it/id/eprint/3104
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3104
2016-02-22T10:57:37Z
Expertise leads to a more efficient brain utilization: an fMRI study in professional and naïve car drivers during attention and visual-spatial tasks
Lorenzo Sani
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Alessandra Papasogli
Riccardo Ceccarelli
Ferdinando Franzoni
Gino Santoro
Rainer Goebel
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-02-22T10:50:55Z
2016-09-13T09:57:53Z
http://eprints.imtlucca.it/id/eprint/3103
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3103
2016-02-22T10:50:55Z
Motor familiarity modulates mirror neurons system activity during auditory action recognition in sighted and congenitally blind individuals
Daniela Bonino
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Lorenzo Sani
Tomaso Vecchi
Mario Guazzelli
James V. Haxby
Luciano Fadiga
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-02-22T10:48:55Z
2016-09-13T10:02:18Z
http://eprints.imtlucca.it/id/eprint/3102
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3102
2016-02-22T10:48:55Z
Functional development of the mirror neuron system does not require visual experience: an fMRI study in sighted and congenitally blind individuals
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Daniela Bonino
Lorenzo Sani
Tomaso Vecchi
Mario Guazzelli
James V. Haxby
Luciano Fadiga
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-02-22T10:44:47Z
2016-09-13T09:57:16Z
http://eprints.imtlucca.it/id/eprint/3101
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3101
2016-02-22T10:44:47Z
Tactile spatial working memory activates the dorsal extrastriate cortical pathway in congenitally blind individuals
In sighted individuals, both the visual and tactile version of the same spatial working memory task elicited neural responses in the dorsal "where" cortical pathway (Ricciardi et al., 2006). Whether the neural response during the tactile working memory task is due to visually-based spatial imagery or rather reflects a more abstract, supramodal organization of the dorsal cortical pathway remains to be determined. To understand the role of visual experience on the functional organization of the dorsal cortical stream, using functional magnetic resonance imaging (fMRI) here we examined brain response in four individuals with congenital or early blindness and no visual recollection, while they performed the same tactile spatial working memory task, a one-back recognition of 2D and 3D matrices. The blind subjects showed a significant activation in bilateral posterior parietal cortex, dorsolateral and inferior prefrontal areas, precuneus, lateral occipital cortex, and cerebellum. Thus, dorsal occipito-parietal areas are involved in mental imagery dealing with spatial components in subjects without prior visual experience and in response to a non-visual task. These data indicate that recruitment of the dorsal cortical pathway in response to the tactile spatial working memory task is not mediated by visually-based imagery and that visual experience is not a prerequisite for the development of a more abstract functional organization of the dorsal stream. These findings, along with previous data indicating a similar supramodal functional organization within the ventral cortical pathway and the motion processing brain regions, may contribute to explain how individuals who are born deprived of sight are able to interact effectively with the surrounding world.
Daniela Bonino
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Lorenzo Sani
Claudio Gentili
Nicola Vanello
Mario Guazzelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-02-22T10:41:48Z
2016-09-13T09:56:48Z
http://eprints.imtlucca.it/id/eprint/3100
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3100
2016-02-22T10:41:48Z
Sensing Glove for Brain Studies: Design and Assessment of Its Compatibility for fMRI With a Robust Test
In this paper, we describe a biomimetic-fabric-based sensing glove that can be used to monitor hand posture and gesture. Our device is made of a distributed sensor network of piezoresistive conductive elastomers integrated into an elastic fabric. This solution does not affect natural movement and hand gestures, and can be worn for a long time with no discomfort. The glove could be fruitfully employed in behavioral and functional studies with functional MRI (fMRI) during specific tactile or motor tasks. To assess MR compatibility of the system, a statistical test on phantoms is introduced. This test can also be used for testing the compatibility of mechatronic devices designed to produce different stimuli inside the MR environment. We propose a statistical test to evaluate changes in SNR and time-domain standard deviations between image sequences acquired under different experimental conditions. fMRI experiments on subjects wearing the glove are reported. The reproducibility of fMRI results obtained with and without the glove was estimated. A good similarity between the activated regions was found in the two conditions.
Nicola Vanello
Valentina Hartwig
Mario Tesconi
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Alessandro Tognetti
Giuseppe Zupone
Roger Gassert
Dominique Chapuis
Nicola Sgambelluri
Enzo Pasquale Scilingo
Giulio Giovannetti
Vincenzo Positano
Maria Filomena Santarelli
Antonio Bicchi
Pietro Pietrini
pietro.pietrini@imtlucca.it
Danilo De Rossi
Luigi Landini
2016-02-22T10:36:49Z
2016-09-13T10:07:12Z
http://eprints.imtlucca.it/id/eprint/3099
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3099
2016-02-22T10:36:49Z
A sensing glove for enhancing exploration of brain functions in haptic tasks
Nicola Vanello
Valentina Hartwig
Mario Tesconi
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Alessandro Tognetti
Giuseppe Zupone
Enzo Pasquale Scilingo
Giulio Giovannetti
Vincenzo Positano
Maria Filomena Santarelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
Danilo De Rossi
Luigi Landini
Antonio Bicchi
2016-02-22T10:26:34Z
2016-09-13T09:58:04Z
http://eprints.imtlucca.it/id/eprint/3098
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3098
2016-02-22T10:26:34Z
Spatiotemporal dynamics of single-letter reading: a combined ERP-FMRI study
This work investigates the neural correlates of single-letter reading by combining event-related potentials (ERPs) and functional magnetic resonance imaging (fMRI), thus exploiting their complementary spatiotemporal resolutions. Three externally-paced reading tasks were administered with an event-related design: passive observation of letters and symbols and active reading aloud of letters. ERP and fMRI data were separately recorded from 8 healthy adults during the same experimental conditions. Due to the presence of artifacts in the EEG signals, two subjects were discarded from further analysis. Independent Component Analysis was applied to ERPs, after dimensionality reduction by Principal Component Analysis: some independent components were clearly related to specific reading functions and the associated current density distributions in the brain were estimated with Low Resolution Electromagnetic Tomography Analysis method (LORETA). The impulse hemodynamic response function was modeled as a linear combination of linear B-spline functions and fMRI statistical analysis was performed by multiple linear regression. fMRI and LORETA maps were superimposed in order to identify the overlapping activations and the activated regions specifically revealed by each modality. The results showed the existence of neuronal networks functionally specific for letter processing and for explicit verbal-motor articulation, including the temporo-parietal and frontal regions. Overlap between fMRI and LORETA results was observed in the inferior temporal-middle occipital gyrus, suggesting that this area has a crucial and multifunctional role for linguistic and reading processes, likely because its spatial location and strong interconnection with the main visual and auditory sensory systems may have favored its specialization in grapheme-phoneme matching.
Silvia Casarotto
A.M. Bianchi
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Claudio Gentili
Nicola Vanello
Mario Guazzelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
Giuseppe A. Chiarenza
Sergio Cerutti
2016-02-22T10:18:53Z
2016-09-13T10:02:30Z
http://eprints.imtlucca.it/id/eprint/3097
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3097
2016-02-22T10:18:53Z
Cholinergic modulation on brain response to working memory as task difficulty increases in young and older subjects
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
Maura L. Furey
2016-02-19T13:03:31Z
2016-09-13T09:57:04Z
http://eprints.imtlucca.it/id/eprint/3095
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3095
2016-02-19T13:03:31Z
Tactile flow explains haptic counterparts of common visual illusions
Interaction with the external world requires the ability to perceive dynamic changes in complex sensorial input and react promptly. Here, we show that perception of dynamic stimuli in the visual and tactile sensory modalities share fundamental psychophysical aspects that can be explained by similar computational models. In vision, optic flow provides information on relative motion between the individual and the content of percept. For instance, radial patterns of optic flow are used to estimate time before contact with an approaching object J.J. Gibson, What gives rise to the perception of motion? Psychol. Rev. 75 (1968) 335–346. Similarly, in the tactile modality, radial patterns of stimuli provide information on softness of probed objects A. Bicchi, D. De Rossi, E.P. Scilingo, The role of the contact area spread rate (CASR) in haptic discrimination of softness, \{IEEE\} Trans. Rob. Autom. 16 (2000) 496–504. Optic flow is also invoked to explain several visual illusions, including the well-known “barber-pole” effect N. Fisher, J.M. Zanker, The directional tuning of the barber-pole illusion, Perception 30 (2001) 1321–1336. Here, we introduce a computational model of tactile flow, which is intimately related to existing models for the visual counterpart. The model accounts for psychophysical aspects of dynamic tactile perception and predicts illusory phenomena in the tactile domain, analogous to the barber-pole effect. When subjects touched translating pads with differently oriented gratings, they perceived a direction of motion that was significantly biased towards the orientation of the gratings. Therefore, these findings indicate that visual and tactile flow share similarities at the psychophysical and computational level and may be intended for similar perceptive goals. Results of this analysis have impact on the engineering of better haptic and multimodal interfaces for human–computer interaction.
Antonio Bicchi
Enzo Pasquale Scilingo
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-02-19T13:01:31Z
2016-09-13T09:59:05Z
http://eprints.imtlucca.it/id/eprint/3094
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3094
2016-02-19T13:01:31Z
Imagery and spatial processes in blindness and visual impairment
The objective of this review is to examine and evaluate recent findings on cognitive functioning (in particular imagery processes) in individuals with congenital visual impairments, including total blindness, low-vision and monocular vision. As one might expect, the performance of blind individuals in many behaviours and tasks requiring imagery can be inferior to that of sighted subjects; however, surprisingly often this is not the case. Interestingly, there is evidence that the blind often employ different cognitive mechanisms than sighted subjects, suggesting that compensatory mechanisms can overcome the limitations of sight loss. Taken together, these studies suggest that the nature of perceptual input on which we commonly rely strongly affects the organization of our mental processes. We also review recent neuroimaging studies on the neural correlates of sensory perception and mental imagery in visually impaired individuals that have cast light on the plastic functional reorganization mechanisms associated with visual deprivation.
Zaira Cattaneo
Tomaso Vecchi
Cesare Cornoldi
Irene Mammarella
Daniela Bonino
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-02-19T12:59:25Z
2016-09-13T10:00:02Z
http://eprints.imtlucca.it/id/eprint/3093
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3093
2016-02-19T12:59:25Z
Cholinergic Enhancement Eliminates Modulation of Neural Activity by Task Difficulty in the Prefrontal Cortex during Working Memory
Previously, we demonstrated that enhancing cholinergic activity during a working memory (WM) task improves performance and reduces blood flow in the right anterior middle/superior frontal cortex, an area known to be important for WM. The purpose of this study was to evaluate the interaction between WM task demands and cholinergic enhancement on neural responses in the prefrontal cortex. Regional cerebral blood flow (rCBF) was measured using H215O and positron emission tomography, as 10 young healthy volunteers performed a parametrically varied match-to-sample WM for faces task. For each item, a picture of a face was presented, followed by a delay (1, 6, 11, or 16 sec), then by the presentation of two faces. Subjects were instructed to identify which face they previously had seen. For control items, nonsense pictures were presented in the same spatial and temporal manner. All conditions were performed during an intravenous infusion of saline and physostigmine (1 mg/hr). Subjects were blind to the substance being infused. Reaction time increased significantly with WM delay, and physostigmine decreased reaction time across delay conditions. Significant task-related rCBF increases during saline infusion were seen in superior frontal, middle frontal, and inferior frontal regions, and the response magnitudes in the regions increased systematically with task difficulty. In all of these prefrontal regions, physostigmine administration significantly reduced rCBF during task, particularly at longer task delays, so that no correlation between task delay and rCBF was observed. In the ventral visual cortex, physostigmine increased rCBF at longer task delays in medial regions, and decreased rCBF over delay conditions in lateral cortical areas. These results indicate that, during cholinergic potentiation, brain activity in prefrontal regions is not modulated by increases in WM task demands, and lends further support to the hypothesis that cholinergic modulation enhances visual processing, making the task easier to perform, and thus, compensate for the need to recruit prefrontal cortical regions as task demands increase.
Maura L. Furey
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Mark B. Schapiro
Stanley I. Rapoport
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-02-19T12:42:01Z
2016-09-13T10:00:28Z
http://eprints.imtlucca.it/id/eprint/3090
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3090
2016-02-19T12:42:01Z
Differential modulation of neural activity throughout the distributed neural system for face perception in patients with Social Phobia and healthy subjects
Social Phobia (SP) is a marked and persistent fear of social or performance situations in which the person is exposed to unfamiliar people or to possible scrutiny by others. Faces of others are perceived as threatening by social phobic patients (SPP). To investigate how face processing is altered in the distributed neural system for face perception in Social Phobia, we designed an event-related fMRI study in which Healthy Controls (HC) and {SPP} were presented with angry, fearful, disgusted, happy and neutral faces and scrambled pictures (visual baseline). As compared to HC, {SPP} showed increased neural activity not only in regions involved in emotional processing including left amygdala and insula, as expected from previous reports, but also in the bilateral superior temporal sulcus (STS), a part of the core system for face perception that is involved in the evaluation of expression and personal traits. In addition {SPP} showed a significantly weaker activation in the left fusiform gyrus, left dorsolateral prefrontal cortex, and bilateral intraparietal sulcus as compared to HC. These effects were found not only in response to emotional faces but also to neutral faces as compared to scrambled pictures. Thus, {SPP} showed enhanced activity in brain areas related to processing of information about emotional expression and personality traits. In contrast, brain activity was decreased in areas for attention and for processing other information from the face, perhaps as a result of a feeling of wariness. These results indicate a differential modulation of neural activity throughout the different parts of the distributed neural system for face perception in {SPP} as compared to HC.
Claudio Gentili
Maria Ida Gobbini
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Nicola Vanello
Pietro Pietrini
pietro.pietrini@imtlucca.it
James V. Haxby
Mario Guazzelli
2016-02-19T12:34:59Z
2016-09-13T10:01:01Z
http://eprints.imtlucca.it/id/eprint/3087
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3087
2016-02-19T12:34:59Z
Imbalanced between attentional and emotional system in social phobics processing social relevant stimulli
Claudio Gentili
Maria Ida Gobbini
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Nicola Vanello
Pietro Pietrini
pietro.pietrini@imtlucca.it
James V. Haxby
Mario Guazzelli
2016-02-19T12:30:14Z
2016-09-13T10:01:13Z
http://eprints.imtlucca.it/id/eprint/3085
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3085
2016-02-19T12:30:14Z
Modulation of specific brain activity by very subtle geometrical perceptual relationships of the Mangina-Test: A functional magnetic resonance imaging study in young healthy adults
Constantine A. Mangina
Helen Beuzeron-Mangina
Silvia Casarotto
Giuseppe A. Chiarenza
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
2016-02-19T12:23:22Z
2016-09-13T10:00:47Z
http://eprints.imtlucca.it/id/eprint/3083
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3083
2016-02-19T12:23:22Z
Imbalanced activation of the distributed neural system for face perception in social phobia
Claudio Gentili
Maria Ida Gobbini
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Nicola Vanello
Pietro Pietrini
pietro.pietrini@imtlucca.it
James V. Haxby
Mario Guazzelli
2016-02-19T12:13:51Z
2016-09-13T09:59:48Z
http://eprints.imtlucca.it/id/eprint/3081
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3081
2016-02-19T12:13:51Z
Tactile perception, emotional responses and personality factors: a preliminary behavioural study
Sabrina Danti
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Claudio Gentili
Mario Guazzelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-02-19T11:46:02Z
2016-09-13T10:01:25Z
http://eprints.imtlucca.it/id/eprint/3079
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3079
2016-02-19T11:46:02Z
Neural correlates of “analytical-specific visual perception” as investigated by the Mangina-Test: A functional magnetic resonance imaging study in young healthy adults
Constantine A. Mangina
Helen Beuzeron-Mangina
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
Giuseppe A. Chiarenza
Silvia Casarotto
2016-02-19T11:37:58Z
2016-09-13T10:06:49Z
http://eprints.imtlucca.it/id/eprint/3078
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3078
2016-02-19T11:37:58Z
Psychophysiological and fMRI neural correlates to stress response: A pilot study
Carlo Pruneti
Nicola Vanello
Rosalba Morese
Claudio Gentili
Federico Fontana
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Chiara Fante
Marco Paterni
Pietro Pietrini
pietro.pietrini@imtlucca.it
Mario Guazzelli
Luigi Landini
Ezio Maria Ferdeghini
2016-02-19T11:32:56Z
2016-09-13T10:00:17Z
http://eprints.imtlucca.it/id/eprint/3077
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3077
2016-02-19T11:32:56Z
The effect of familiarity in metaphor comprehension: An fMRI study
Claudio Gentili
Valentina Bambini
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-02-18T12:10:11Z
2016-09-13T09:59:20Z
http://eprints.imtlucca.it/id/eprint/3072
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3072
2016-02-18T12:10:11Z
Human V4 responds positively to both positive and negative changes in motion coherence from adapted state: An event-related BOLD-fMRI study
Mauro Costagli
Kenichi Ueno
Pei Sun
X.H. Wan
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
Keiji Tanaka
K. Cheng
2016-02-18T10:24:10Z
2016-09-13T09:58:22Z
http://eprints.imtlucca.it/id/eprint/3069
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3069
2016-02-18T10:24:10Z
Covert visual brand recognition results in a distinct modulation of emotional neuronal networks according to the individual preference: a fMRI study
Silvia Casarotto
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
S. Romani
Matteo Corciolani
Daniele Dalli
Pietro Pietrini
pietro.pietrini@imtlucca.it
2016-01-28T11:37:59Z
2017-08-04T10:18:57Z
http://eprints.imtlucca.it/id/eprint/3032
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/3032
2016-01-28T11:37:59Z
Sleep reverts changes in human gray and white matter caused by wake-dependent training
Abstract Learning leads to rapid microstructural changes in gray (GM) and white (WM) matter. Do these changes continue to accumulate if task training continues, and can they be reverted by sleep? We addressed these questions by combining structural and diffusion weighted {MRI} and high-density {EEG} in 16 subjects studied during the physiological sleep/wake cycle, after 12 h and 24 h of intense practice in two different tasks, and after post-training sleep. Compared to baseline wake, 12 h of training led to a decline in cortical mean diffusivity. The decrease became even more significant after 24 h of task practice combined with sleep deprivation. Prolonged practice also resulted in decreased ventricular volume and increased {GM} and {WM} subcortical volumes. All changes reverted after recovery sleep. Moreover, these structural alterations predicted cognitive performance at the individual level, suggesting that sleep's ability to counteract performance deficits is linked to its effects on the brain microstructure. The cellular mechanisms that account for the structural effects of sleep are unknown, but they may be linked to its role in promoting the production of cerebrospinal fluid and the decrease in synapse size and strength, as well as to its recently discovered ability to enhance the extracellular space and the clearance of brain metabolites.
Giulio Bernardi
Luca Cecchetti
luca.cecchetti@imtlucca.it
Francesca Siclari
Andreas Buchmann
Xiaoqian Yu
Giacomo Handjaras
Michele Bellesi
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Steven R. Kecskemeti
Brady A. Riedner
Andrew L. Alexander
Ruth M. Benca
Maria Felice Ghilardi
Pietro Pietrini
pietro.pietrini@imtlucca.it
Chiara Cirelli
Giulio Tononi
2015-12-23T15:17:45Z
2016-09-13T09:55:21Z
http://eprints.imtlucca.it/id/eprint/2976
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2976
2015-12-23T15:17:45Z
Do we really need vision? How blind people "see" the actions of others
Observing and learning actions and behaviors from others, a mechanism crucial for survival and social interaction, engages the mirror neuron system. To determine whether vision is a necessary prerequisite for the human mirror system to develop and function, we used functional magnetic resonance imaging to compare brain activity in congenitally blind individuals during the auditory presentation of hand-executed actions or environmental sounds, and the motor pantomime of manipulation tasks, with that in sighted volunteers, who additionally performed a visual action recognition task. Congenitally blind individuals activated a premotor–temporoparietal cortical network in response to aurally presented actions that overlapped both with mirror system areas found in sighted subjects in response to visually and aurally presented stimuli, and with the brain response elicited by motor pantomime of the same actions. Furthermore, the mirror system cortex showed a significantly greater response to motor familiar than to unfamiliar action sounds in both sighted and blind individuals. Thus, the mirror system in humans can develop in the absence of sight. The results in blind individuals demonstrate that the sound of an action engages the mirror system for action schemas that have not been learned through the visual modality and that this activity is not mediated by visual imagery. These findings indicate that the mirror system is based on supramodal sensory representations of actions and, furthermore, that these abstract representations allow individuals with no visual experience to interact effectively with others.
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Daniela Bonino
Lorenzo Sani
Tomaso Vecchi
Mario Guazzelli
James V. Haxby
Luciano Fadiga
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-12-04T14:16:51Z
2016-09-13T09:53:46Z
http://eprints.imtlucca.it/id/eprint/2969
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2969
2015-12-04T14:16:51Z
The nature of consciousness in the visually-deprived brain
Vision plays a central role in how we represent and interact with the world around us. The primacy of vision is structurally imbedded in cortical organization as about one-third of the cortical surface in primates is involved in visual processes. Consequently, the loss of vision, either at birth or later in life, affects brain organization and the way the world is perceived and acted upon. In this paper, we address a number of issues on the nature of consciousness in people deprived of vision. Do brains from sighted and blind individuals differ, and how? How does the brain of someone who has never had any visual perception form an image of the external world? What is the subjective correlate of activity in the visual cortex of a subject who has never seen in life? More in general, what can we learn about the functional development of the human brain in physiological conditions by studying blindness? We discuss findings from animal research as well from recent psychophysical and functional brain imaging studies in sighted and blind individuals that shed some new light on the answers to these questions.
Ron Kupers
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Maurice Ptito
2015-12-02T15:47:05Z
2016-09-13T09:55:50Z
http://eprints.imtlucca.it/id/eprint/2960
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2960
2015-12-02T15:47:05Z
Cholinergic modulation of visual working memory during aging: a parametric PET study
Age-related differences in the regional recruitment of prefrontal cortex (PFC) during cognitive tasks suggests that aging is associated with functional reorganization. Cholinergic enhancement with physostigmine reduces activity in the {PFC} regions selectively recruited during working memory (WM) and increases activity in visual processing areas, suggesting that augmenting cholinergic function reduces task effort by improving the visual representation of {WM} stimuli. Here, we investigated how cholinergic enhancement influenced {PFC} and visual cortical activity in young and older subjects as {WM} difficulty was altered. Regional cerebral blood flow (rCBF) was measured using H215O-PET in 10 young and 10 older volunteers during a parametrically varied face {WM} task, following an i.v. infusion of saline and physostigmine. Reaction time decreased during physostigmine relative to placebo in both groups. Prefrontal brain regions selectively recruited in each age group that responded differentially to task demands during placebo, had no significant activity during physostigmine. Medial visual processing areas showed task-selective increases in activity during drug in both groups, while lateral regions showed decreased activity in young and increased activity in older participants at longer task delays. These results are consistent with our previous findings, showing that the modulatory role of the cholinergic system persists during aging, and that the effects of cholinergic enhancement are functionally specific rather than anatomically specific. Moreover, the use of the parametric design allowed us to uncover group specific effects in lateral visual processing areas where increasing cholinergic function produced opposite effects on neural activity in the two age groups.
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
Mark B. Schapiro
Stanley I. Rapoport
Maura L. Furey
2015-12-02T15:36:51Z
2016-09-13T09:55:34Z
http://eprints.imtlucca.it/id/eprint/2959
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2959
2015-12-02T15:36:51Z
Neural correlates of “analytical-specific visual perception” and degree of task difficulty as investigated by the Mangina-Test: A functional magnetic resonance imaging (fMRI) study in young healthy adults
The Mangina-Test is a neuropsychometric method for evaluating varying degrees of “analytical-specific perception” as they relate to learning abilities and disabilities. It consists of the identification of simple stimuli which are masked within a complex configuration according to their exact size, dimension, direction, spatial orientation, and shape within a limited span of time. This test has been successfully applied in clinical settings for the assessment of cognitive abilities and disorders in young and elderly populations. This investigation aimed to examine the neural correlates of analytical-specific visual perceptual processes as measured by the Mangina-Test. Functional Magnetic Resonance Imaging (fMRI) was recorded during the administration of a computer-adapted version of the Mangina-Test in twelve young healthy adults. Multiple linear regression analysis was applied to estimate the overall brain activation during task accomplishment. In addition, the fMRI response area was correlated with task difficulty, in order to explore the spatial distribution of brain regions modulated by increasing task demand. Results indicate that a widely distributed bilateral network of brain regions, including the ventral and dorsal occipital cortex, parietal lobule, frontal and supplementary eye field, dorsolateral prefrontal cortex, and supplementary motor area, was significantly activated during test performance. Moreover, increasing difficulty significantly enhanced the neural response of ventral and dorsal occipital regions, frontal eye field, and superior parietal sulcus bilaterally, as well as the right dorsolateral prefrontal cortex. Conversely, neural activity in the left temporo-parietal junction, inferior frontal gyrus, and bilateral middle-superior temporal cortex was inversely correlated with task difficulty. Results also indicate that performance in the Mangina-Test requires an optimal integration between the enhancement of activity in specific task-related cortical areas and suppression of interfering noise from unrelated brain regions.
Constantine A. Mangina
Helen Beuzeron-Mangina
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
Giuseppe A. Chiarenza
Silvia Casarotto
2015-12-02T15:24:06Z
2016-09-13T09:55:03Z
http://eprints.imtlucca.it/id/eprint/2958
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2958
2015-12-02T15:24:06Z
Beyond amygdala: default mode network activity differs between patients with social phobia and healthy controls
The Default Mode Network (DMN) is a constellation of brain areas that decrease their activity during a wide number of different goal-oriented tasks as compared to passive “rest” tasks. {DMN} can be modulated by different factors such as emotional states, cognitive load of the task and psychopathology, including anxiety. Moreover, {DMN} seems to play a pivotal role in social cognition. For example, the ability to predict another person's behaviour taking his or her perspective modulates the activity of the DMN. Recent data from autistic patients support a role of {DMN} in social cognition as well. Social Phobia (SP) is an anxiety disorder characterized by an abnormal distress in situations that require social interaction. To date, no study has assessed {DMN} in Social Phobia. To determine potential differences in {DMN} activity between Social Phobia patients (SPP) and healthy control (HC) subjects we examined functional magnetic resonance imaging (fMRI) data obtained during a face perception study with emotional and neutral stimuli. As compared to HC, {SPP} showed a lower deactivation in the precuneus and posterior cingulate regions (PCun/PCC) during task conditions. These regions are part of the so-called “Theory of Mind” circuit and in particular they are involved in the evaluation of one's own emotional state. Because of the role of the PCun/PCC in self-state perception and attribution and, more in general, the role of the {DMN} in social cognition, we suggest that its impairment in the {DMN} network in {SPP} might be relevant in the development of the feeling of wariness of others’ judgment and may be related to the so-called self-focused attention. Self-focused attention is the awareness of self-referent information, and is present in many emotional disorders and may additionally prevent individuals from observing external information that could disconfirm their own fears. Moreover, the abnormal modulation of activity in the {DMN} may reflect persistent rumination or anxiety-related thoughts that are not modulated by the switch from rest to task.
Claudio Gentili
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Maria Ida Gobbini
Maria Filomena Santarelli
James V. Haxby
Pietro Pietrini
pietro.pietrini@imtlucca.it
Mario Guazzelli
2015-12-02T14:45:09Z
2016-09-13T09:56:06Z
http://eprints.imtlucca.it/id/eprint/2957
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2957
2015-12-02T14:45:09Z
Modulation of specific brain activity by the perceptual analysis of very subtle geometrical relationships of the Mangina-Test stimuli: a functional magnetic resonance imaging (fMRI) investigation in young healthy adults
The Mangina-Test provides a neuropsychometric assessment of varying degrees of “Analytical-Specific Visual Perception”, i.e., the ability to identify simple stimuli inserted into more complex ones according to their exact geometrical properties in a limited span of time. Perceptual analysis of stimuli dealing with the exact discrimination of size and dimension is related more to mathematical abilities (MATH), while perceptual analysis of direction and spatial orientation is related more to abilities in reading and reading comprehension (READ). Some stimuli are {MIXED} since they deal with both of the above features combined. We previously determined the distributed neuronal network of analytical-specific visual perceptual processes as measured by the Mangina-Test. Here, we aim at further assessing as to how brain activity is differentially modulated by the discrimination of very subtle category-specific perceptual relationships. Brain activity was measured by functional magnetic resonance imaging in 12 young healthy subjects while they performed a computer-adapted version of the Mangina-Test. Behavioral results of the present study indicate that performance was not different among stimulus categories. However, brain functional data show that analytical-specific perceptual processes for MATH, {READ} and {MIXED} stimuli rely on partially distinct brain circuits. Bilateral posterior parietal, premotor and prefrontal regions along with the anterior cingulate appeared to be more activated by {MATH} stimuli, while {READ} stimuli predominantly activated bilateral medial occipito-temporal, amygdala/parahippocampal and sensorimotor cortices, and the right inferior frontal cortex. Moreover, the posterior parahippocampal cortex showed a higher activity specifically for {MIXED} stimuli. Altogether, these findings demonstrate that in the Mangina-Test, the exact discrimination of very subtle perceptual relationships between geometrical stimuli distinctly modulates cerebral activity, so that category-specific brain responses can be related to identifiable cognitive abilities.
Constantine A. Mangina
Helen Beuzeron-Mangina
Silvia Casarotto
Giuseppe A. Chiarenza
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
2015-12-01T12:42:36Z
2016-09-13T09:53:21Z
http://eprints.imtlucca.it/id/eprint/2942
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2942
2015-12-01T12:42:36Z
Conditional granger causality analysis of fMRI data shows a direct connection from LGN to hMT+ bypassing V1
The human middle temporal complex (hMT+) is devoted to motion perception. To determine whether motion-related neural information may reach hMT+ directly from the thalamus, by-passing the primary visual cortex (V1), we measured effective connectivity in an optic flow fMRI experiment in humans. Conditional Granger Causality analysis was employed to measure direct influences between the lateral geniculate nucleus (LGN) and hMT+, discarding indirect effects mediated by V1. Results indicated the existence of a bilateral alternative pathway for visual motion processing that allows for a direct flow of information from LGN to hMT+. This direct link may play a role in blindsight.
Anna Gaglianese
Mauro Costagli
Giulio Bernardi
Lorenzo Sani
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-24T12:56:57Z
2016-09-13T09:53:34Z
http://eprints.imtlucca.it/id/eprint/2934
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2934
2015-11-24T12:56:57Z
Functional inhibition of the human middle temporal cortex affects non-visual motion perception: a repetitive transcranial magnetic stimulation study during tactile speed discrimination
The visual motion-responsive middle temporal complex (hMT+) is activated during tactile and aural motion discrimination in both sighted and congenitally blind individuals, suggesting a supramodal organization of this area. Specifically, non-visual motion processing has been found to activate the more anterior portion of the hMT+. In the present study, repetitive transcranial magnetic stimulation (rTMS) was used to determine whether this more anterior portion of hMT+ truly plays a functional role in tactile motion processing. Sixteen blindfolded, young, healthy volunteers were asked to detect changes in the rotation velocity of a random Braille-like dot pattern by using the index or middle finger of their right hand. rTMS was applied for 600 ms (10 Hz, 110% motor threshold), 200 ms after the stimulus onset with a figure-of-eight coil over either the anterior portion of hMT+ or a midline parieto-occipital site (as a control). Accuracy and reaction times were significantly impaired only when TMS was applied on hMT+, but not on the control area. These results indicate that the recruitment of hMT+ is necessary for tactile motion processing, and thus corroborate the hypothesis of a ‘supramodal’ functional organization for this sensory motion processing area.
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Demis Basso
Lorenzo Sani
Daniela Bonino
Tomaso Vecchi
Pietro Pietrini
pietro.pietrini@imtlucca.it
Carlo Miniussi
2015-11-24T12:38:55Z
2016-09-13T09:52:11Z
http://eprints.imtlucca.it/id/eprint/2933
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2933
2015-11-24T12:38:55Z
New light from the dark: what blindness can teach us about brain function
Purpose of review: In this review, we discuss findings from some recent brain imaging studies that shed new light on our understanding of the role of visual experience on the development of the brain morphological and functional architecture in humans. To what extent is vision truly necessary to ‘see’ the world around us?
Recent findings: Congenitally blind and sighted individuals present analogous cognitive and social performances. Findings from structural and functional brain studies in both sighted and congenitally blind individuals have shown the existence of supramodal brain regions able to process external information regardless of the sensory modality through which such an information has been acquired. This more abstract nature of functional cortical organization may enable congenitally blind individuals to acquire knowledge, form mental representations of and interact effectively with an external world that they have never seen.
Summary: Altogether, findings from both behavioural and imaging studies indicate that the brain functional organization is to a large extent independent from visual experience and able to process information in a supramodal fashion. The study of the blind brain is a very powerful approach to understanding not only the cross-modal plastic, adaptative modifications that occur in the ‘visual’ regions but primarily the functional architecture of the human brain itself.
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-18T11:23:28Z
2016-09-12T11:46:49Z
http://eprints.imtlucca.it/id/eprint/2923
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2923
2015-11-18T11:23:28Z
A MR Compatible Sensing Glove for Brain Studies
Nicola Vanello
Valentina Hartwig
Mario Tesconi
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Giuseppe Zupone
Alessandro Tognetti
Daniela Bonino
Enzo Pasquale Scilingo
Fabrizio Cutolo
Giulio Giovannetti
Pietro Pietrini
pietro.pietrini@imtlucca.it
Danilo De Rossi
Luigi Landini
2015-11-18T11:19:55Z
2016-09-13T09:54:19Z
http://eprints.imtlucca.it/id/eprint/2922
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2922
2015-11-18T11:19:55Z
Cholinergic Effects in Visual Areas during Object and Spatial Working Memory Encoding: an fMRI study
Giacomo Handjaras
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
James V. Haxby
Pietro Pietrini
pietro.pietrini@imtlucca.it
Maura L. Furey
2015-11-18T11:03:28Z
2016-09-13T09:51:45Z
http://eprints.imtlucca.it/id/eprint/2919
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2919
2015-11-18T11:03:28Z
FMRI Compatible Sensing Glove for Hand Gesture Monitoring
Here we describe and validate a fabric sensing glove for hand finger movement monitoring. After a quick calibration procedure, and by suitably processing of the outputs of the glove, it is possible to estimate hand joint angles in real time. Moreover, we tested the fMRI compatibility of the glove and ran a pilot fMRI experiment on the neural correlates of handshaking during human-to-human and human-to-robot interactions. Here we describe how the glove can be used to monitor correct task execution and to improve modeling of the expected hemodynamic responses during fMRI experimental paradigms.
Nicola Vanello
Valentina Hartwig
Enzo Pasquale Scilingo
Daniela Bonino
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Alessandro Tognetti
Pietro Pietrini
pietro.pietrini@imtlucca.it
Danilo De Rossi
Luigi Landini
Antonio Bicchi
2015-11-18T10:59:48Z
2016-09-13T09:49:55Z
http://eprints.imtlucca.it/id/eprint/2918
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2918
2015-11-18T10:59:48Z
Evidence of a direct influence between the thalamus and hMT + independent of V1 in the human brain as measured by fMRI
In the present study we employed Conditional Granger Causality (CGC) and Coherence analysis to investigate whether visual motion-related information reaches the human middle temporal complex (hMT +) directly from the Lateral Geniculate Nucleus (LGN) of the thalamus, by-passing the primary visual cortex (V1). Ten healthy human volunteers underwent brain scan examinations by functional magnetic resonance imaging (fMRI) during two optic flow experiments. In addition to the classical LGN-V1-hMT + pathway, our results showed a significant direct influence of the blood oxygenation level dependent (BOLD) signal recorded in {LGN} over that in hMT+, not mediated by {V1} activity, which strongly supports the existence of a bilateral pathway that connects {LGN} directly to hMT + and serves visual motion processing. Furthermore, we evaluated the relative latencies among areas functionally connected in the processing of visual motion. Using {LGN} as a reference region, hMT + exhibited a statistically significant earlier peak of activation as compared to V1. In conclusion, our findings suggest the co-existence of an alternative route that directly links {LGN} to hMT+, bypassing V1. This direct pathway may play a significant functional role for the faster detection of motion and may contribute to explain persistence of unconscious motion detection in individuals with severe destruction of primary visual cortex (blindsight).
Anna Gaglianese
Mauro Costagli
Giulio Bernardi
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-18T10:56:40Z
2016-09-13T09:49:20Z
http://eprints.imtlucca.it/id/eprint/2917
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2917
2015-11-18T10:56:40Z
Covert brand recognition engages
emotion-specific brain networks
Consumer goods’ brands have become a major driver of consumers’ choice: they have got symbolic, relational
and even social properties that add substantial cultural and affective value to goods and services. Therefore,
measuring the role of brands in consumers’ cognitive and affective processes would be very helpful to better
understand economic decision making. This work aimed at finding the neural correlates of automatic, spontaneous
emotional response to brands, showing how deeply integrated are consumption symbols within the cognitive
and affective processes of individuals. Functional magnetic resonance imaging (fMRI) was measured during a
visual oddball paradigm consisting in the presentation of scrambled pictures as frequent stimuli, colored squares
as targets, and brands and emotional pictures (selected from the International Affective Picture System [IAPS]) as
emotionally-salient distractors. Affective rating of brands was assessed individually after scanning by a validated
questionnaire. Results showed that, similarly to IAPS pictures, brands activated a well-defined emotional network,
including amygdala and dorsolateral prefrontal cortex, highly specific of affective valence. In conclusion, this work
identified the neural correlates of brands within cognitive and affective processes of consumers.
Silvia Casarotto
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
S. Romani
Daniele Dalli
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-18T10:45:00Z
2016-09-13T09:48:25Z
http://eprints.imtlucca.it/id/eprint/2916
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2916
2015-11-18T10:45:00Z
Touching Motion: rTMS on the Human Middle Temporal Complex Interferes with Tactile Speed Perception
Brain functional and psychophysical studies have clearly demonstrated that visual motion perception relies on the activity of the middle temporal complex (hMT+). However, recent studies have shown that hMT+ seems to be also activated during tactile motion perception, suggesting that this visual extrastriate area is involved in the processing and integration of motion, irrespective of the sensorial modality. In the present study, we used repetitive transcranial magnetic stimulation (rTMS) to assess whether hMT+ plays a causal role in tactile motion processing. Blindfolded participants detected changes in the speed of a grid of tactile moving points with their finger (i.e. tactile modality). The experiment included three different conditions: a control condition with no TMS and two TMS conditions, i.e. hMT+-rTMS and posterior parietal cortex (PPC)-rTMS. Accuracies were significantly impaired during hMT+-rTMS but not in the other two conditions (No-rTMS or PPC-rTMS), moreover, thresholds for detecting speed changes were significantly higher in the hMT+-rTMS with respect to the control TMS conditions. These findings provide stronger evidence that the activity of the hMT+ area is involved in tactile speed processing, which may be consistent with the hypothesis of a supramodal role for that cortical region in motion processing.
Demis Basso
Andrea Pavan
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Sabrina Fagioli
Tomaso Vecchi
Carlo Miniussi
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-18T10:41:55Z
2016-09-13T09:50:51Z
http://eprints.imtlucca.it/id/eprint/2915
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2915
2015-11-18T10:41:55Z
The neural mechanisms of reliability weighted integration of shape information from vision and touch
Behaviourally, humans have been shown to integrate multisensory information in a statistically-optimal fashion by averaging the individual unisensory estimates according to their relative reliabilities. This form of integration is optimal in that it yields the most reliable (i.e. least variable) multisensory percept. The present study investigates the neural mechanisms underlying integration of visual and tactile shape information at the macroscopic scale of the regional {BOLD} response. Observers discriminated the shapes of ellipses that were presented bimodally (visual–tactile) or visually alone. A 2 × 5 factorial design manipulated (i) the presence vs. absence of tactile shape information and (ii) the reliability of the visual shape information (five levels). We then investigated whether regional activations underlying tactile shape discrimination depended on the reliability of visual shape. Indeed, in primary somatosensory cortices (bilateral BA2) and the superior parietal lobe the responses to tactile shape input were increased when the reliability of visual shape information was reduced. Conversely, tactile inputs suppressed visual activations in the right posterior fusiform gyrus, when the visual signal was blurred and unreliable. Somatosensory and visual cortices may sustain integration of visual and tactile shape information either via direct connections from visual areas or top-down effects from higher order parietal areas.
Hannah B. Helbig
Marc O. Ernst
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
Axel Thielscher
Katja M. Mayer
Johannes Schultz
Uta Noppeney
2015-11-18T10:34:31Z
2017-08-04T10:19:56Z
http://eprints.imtlucca.it/id/eprint/2913
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2913
2015-11-18T10:34:31Z
Spatial processing in the human dorsal pathway relies on supramodal functional connectivity maps
Luca Cecchetti
luca.cecchetti@imtlucca.it
Giacomo Handjaras
Giulio Bernardi
Daniela Bonino
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-18T10:30:20Z
2016-09-13T09:51:22Z
http://eprints.imtlucca.it/id/eprint/2912
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2912
2015-11-18T10:30:20Z
Cholinergic enhancement reduces functional connectivity and BOLD variability in visual extrastriate cortex during selective attention
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Giacomo Handjaras
Giulio Bernardi
Pietro Pietrini
pietro.pietrini@imtlucca.it
Maura L. Furey
2015-11-18T10:18:00Z
2016-09-13T09:50:23Z
http://eprints.imtlucca.it/id/eprint/2911
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2911
2015-11-18T10:18:00Z
Ventral and Dorsal Stream Dissociation During Action Recognition in the Human Brain
Giacomo Handjaras
Giulio Bernardi
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
2015-11-17T11:25:36Z
2016-09-13T09:48:43Z
http://eprints.imtlucca.it/id/eprint/2907
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2907
2015-11-17T11:25:36Z
Expertise modulates brain activity during passive driving: a study in professional and naïve drivers
Giulio Bernardi
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Giacomo Handjaras
Ferdinando Franzoni
Fabio Galetta
Gino Santoro
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-13T12:16:11Z
2016-09-13T09:52:01Z
http://eprints.imtlucca.it/id/eprint/2896
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2896
2015-11-13T12:16:11Z
Decomposing metaphor processing at the cognitive and neural level through functional magnetic resonance imaging
Prior neuroimaging studies on metaphor comprehension have tended to focus on the role of the right hemisphere, without reaching consensus and leaving aside the functional architecture of this process. The present work aimed to break down metaphor comprehension into its functional components. The study rationale is two-fold: on the one hand, the large-scale network model as emerging in cognitive neuroscience led us to a consideration of metaphor as supported by a distributed and bilateral network; on the other hand, we based on the accounts of figurative language put forward in pragmatics and cognitive science to postulate a decomposition of such a network into multiple sub-systems. During scanning, participants implicitly processed metaphorical (familiar and unfamiliar) and non-metaphorical passages, while being explicitly involved in an adjective matching task to be performed after reading the target passages. Several regions showed greater activity to metaphors as compared to non-metaphors, including left and right inferior frontal gyrus, right superior temporal gyrus, left angular gyrus, and anterior cingulate. This pattern of activations, markedly bilateral, can be decomposed into circumscribed functional sub-systems mediating different aspects of metaphor resolution, as foreseen in the pragmatic and cognitive literature: (a) the conceptual/pragmatic machinery in the bilateral inferior frontal gyrus and in the left angular gyrus, which supports the integration of linguistic material and world knowledge in context; (b) the attentional component in the anterior cingulate and prefrontal areas, which is set to monitor and filter for the relevant aspects of context and for the appropriate meanings; (c) the Theory of Mind system along the right superior temporal sulcus, which deals with the recognition of speakers’ communicative intentions and is more extensively activated by unfamiliar metaphors. The results have several implications for the field of neuropragmatics, especially on the neuropsychological side and on the right hemisphere hypothesis.
Valentina Bambini
Claudio Gentili
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pier Marco Bertinetto
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-11T16:19:51Z
2016-09-13T09:52:23Z
http://eprints.imtlucca.it/id/eprint/2895
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2895
2015-11-11T16:19:51Z
Distinct neural systems involved in agency and animacy detection
We designed an fMRI experiment comparing perception of human faces and robotic faces producing emotional expressions. The purpose of our experiment was to investigate engagement of different parts of the social brain by viewing these animate and inanimate agents. Both human and robotic face expressions evoked activity in face-responsive regions in the fusiform gyrus and STS and in the putative human mirror neuron system. These results suggest that these areas mediate perception of agency, independently of whether the agents are living or not. By contrast, the human faces evoked stronger activity than did robotic faces in the medial pFC and the anterior temporal cortex—areas associated with the representation of others' mental states (theory of mind), whereas robotic faces evoked stronger activity in areas associated with perception of objects and mechanical movements. Our data demonstrate that the representation of the distinction between animate and inanimate agents involves areas that participate in attribution of mental stance.
Maria Ida Gobbini
Claudio Gentili
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Claudia Bellucci
Pericle Salvini
Cecilia Laschi
Mario Guazzelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-11T15:27:34Z
2016-09-13T09:47:16Z
http://eprints.imtlucca.it/id/eprint/2893
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2893
2015-11-11T15:27:34Z
Hypersensitivity to pain in congenital blindness
Vision is important for avoiding encounters with objects in the environment that may imperil physical integrity. We tested whether, in the absence of vision, a lower pain threshold would arise from an adaptive shift to other sensory channels. We therefore measured heat and cold pain thresholds and responses to suprathreshold heat stimuli in 2 groups of congenitally blind and matched normal‐sighted participants. We also assessed detection thresholds for innocuous warmth and cold, and participants’ attitude toward painful encounters in daily life. Our results show that, compared to sighted subjects, congenitally blind subjects have lower heat pain thresholds, rate suprathreshold heat pain stimuli as more painful, and have increased sensitivity for cold pain stimuli. Thresholds for nonpainful thermal stimulation did not differ between groups. The results of the pain questionnaires further indicated that blind subjects are more attentive to signals of external threats. These findings indicate that the absence of vision from birth induces a hypersensitivity to painful stimuli, lending new support to a model of sensory integration of vision and pain processing.
Hocine Slimani
Sabrina Danti
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
Maurice Ptito
Ron Kupers
2015-11-11T15:09:01Z
2016-09-13T09:46:52Z
http://eprints.imtlucca.it/id/eprint/2892
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2892
2015-11-11T15:09:01Z
How the brain heals emotional wounds: the functional neuroanatomy of forgiveness
In life, everyone goes through hurtful events caused by significant others: a deceiving friend, a betraying partner, or an unjustly blaming parent. In response to painful emotions, individuals may react with anger, hostility, and the desire for revenge. As an alternative, they may decide to forgive the wrongdoer and relinquish resentment. In the present study, we examined the brain correlates of forgiveness using functional Magnetic Resonance Imaging (fMRI). Healthy participants were induced to imagine social scenarios that described emotionally hurtful events followed by the indication to either forgive the imagined offenders, or harbor a grudge toward them. Subjects rated their imaginative skills, levels of anger, frustration, and/or relief when imagining negative events as well as following forgiveness. Forgiveness was associated with positive emotional states as compared to unforgiveness. Granting forgiveness was associated with activations in a brain network involved in theory of mind, empathy, and the regulation of affect through cognition, which comprised the precuneus, right inferior parietal regions, and the dorsolateral prefrontal cortex. Our results uncovered the neuronal basis of reappraisal-driven forgiveness, and extend extant data on emotional regulation to the resolution of anger and resentment following negative interpersonal events.
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Giuseppina Rota
Lorenzo Sani
Claudio Gentili
Anna Gaglianese
Mario Guazzelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-11T10:34:47Z
2017-08-04T10:19:38Z
http://eprints.imtlucca.it/id/eprint/2891
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2891
2015-11-11T10:34:47Z
Brain modeling of noun representations in sighted and blind individuals
Giacomo Handjaras
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
A. Lenci
Andrea Leo
Luca Cecchetti
luca.cecchetti@imtlucca.it
G. Marotta
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-10T13:25:28Z
2016-09-13T09:47:28Z
http://eprints.imtlucca.it/id/eprint/2885
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2885
2015-11-10T13:25:28Z
Cholinergic enhancement differentially modulates neural response to encoding during face identity and face location working memory tasks
Potentiation of cholinergic transmission influences stimulus processing by enhancing signal detection through suppression and/or filtering out of irrelevant information (bottom-up modulation) and with top-down task-oriented executive mechanisms based on the recruitment of prefrontal and parietal attentional systems. The cholinergic system also plays a critical role in working memory (WM) processes and preferentially modulates WM encoding, likely through stimulus-processing mechanisms. Previous research reported increased brain responses in visual extrastriate cortical regions during cholinergic enhancement in the encoding phase of WM, independently addressing object and spatial encoding. The current study used functional magnetic resonance imaging to determine the effects of cholinergic enhancement on encoding of key visual processing features. Subjects participated in two scanning sessions, one during an intravenous (i.v.) infusion of saline and the other during an infusion of the acetylcholinesterase inhibitor physostigmine. In each scan session, subjects alternated between a face identity recognition and a spatial location WM. Enhanced cholinergic function increased neural activity in the ventral stream during encoding of face identity and in the dorsal stream during encoding of face location. Conversely, a reduction in brain response was found for scrambled sensorimotor control images. The cholinergic effects on neural activity in the ventral stream during encoding of face identity were stronger than those observed in the dorsal stream during encoding of face location, likely as a consequence of the role of acetylcholine in establishing the inherently relevant nature of face identity. Despite the limited sample-size, the results suggest the stimulus-dependent role of cholinergic system in signal detection, as they show that cholinergic potentiation enhances neural activity in regions associated with early perceptual processing in a selective manner depending on the attended stimulus feature.
Giacomo Handjaras
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Joanna Szczepanik
Pietro Pietrini
pietro.pietrini@imtlucca.it
Maura L. Furey
2015-11-10T13:21:36Z
2016-09-13T09:51:04Z
http://eprints.imtlucca.it/id/eprint/2884
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2884
2015-11-10T13:21:36Z
Increased BOLD Variability in the Parietal Cortex and Enhanced Parieto-Occipital Connectivity during Tactile Perception in Congenitally Blind Individuals
Previous studies in early blind individuals posited a possible role of parieto-occipital connections in conveying nonvisual information to the visual occipital cortex. As a consequence of blindness, parietal areas would thus become able to integrate a greater amount of multimodal information than in sighted individuals. To verify this hypothesis, we compared fMRI-measured BOLD signal temporal variability, an index of efficiency in functional information integration, in congenitally blind and sighted individuals during tactile spatial discrimination and motion perception tasks. In both tasks, the BOLD variability analysis revealed many cortical regions with a significantly greater variability in the blind as compared to sighted individuals, with an overlapping cluster located in the left inferior parietal/anterior intraparietal cortex. A functional connectivity analysis using this region as seed showed stronger correlations in both tasks with occipital areas in the blind as compared to sighted individuals. As BOLD variability reflects neural integration and processing efficiency, these cross-modal plastic changes in the parietal cortex, even if described in a limited sample, reinforce the hypothesis that this region may play an important role in processing nonvisual information in blind subjects and act as a hub in the cortico-cortical pathway from somatosensory cortex to the reorganized occipital areas.
Andrea Leo
Giulio Bernardi
Giacomo Handjaras
Daniela Bonino
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-10T13:06:53Z
2016-09-13T09:47:03Z
http://eprints.imtlucca.it/id/eprint/2880
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2880
2015-11-10T13:06:53Z
How skill expertise shapes the brain functional architecture: an fMRI study of visuo-spatial and motor processing in professional racing-car and naïve drivers
The present study was designed to investigate the brain functional architecture that subserves visuo-spatial and motor processing in highly skilled individuals. By using functional magnetic resonance imaging (fMRI), we measured brain activity while eleven Formula racing-car drivers and eleven ‘naïve’ volunteers performed a motor reaction and a visuo-spatial task. Tasks were set at a relatively low level of difficulty such to ensure a similar performance in the two groups and thus avoid any potential confounding effects on brain activity due to discrepancies in task execution. The brain functional organization was analyzed in terms of regional brain response, inter-regional interactions and blood oxygen level dependent (BOLD) signal variability. While performance levels were equal in the two groups, as compared to naïve drivers, professional drivers showed a smaller volume recruitment of task-related regions, stronger connections among task-related areas, and an increased information integration as reflected by a higher signal temporal variability. In conclusion, our results demonstrate that, as compared to naïve subjects, the brain functional architecture sustaining visuo-motor processing in professional racing-car drivers, trained to perform at the highest levels under extremely demanding conditions, undergoes both ‘quantitative’ and ‘qualitative’ modifications that are evident even when the brain is engaged in relatively simple, non-demanding tasks. These results provide novel evidence in favor of an increased ‘neural efficiency’ in the brain of highly skilled individuals.
Giulio Bernardi
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Lorenzo Sani
Anna Gaglianese
Alessandra Papasogli
Riccardo Ceccarelli
Ferdinando Franzoni
Fabio Galetta
Gino Santoro
Rainer Goebel
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-10T13:05:06Z
2016-09-13T09:51:33Z
http://eprints.imtlucca.it/id/eprint/2881
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2881
2015-11-10T13:05:06Z
Where the brain appreciates the final state of an event: The neural correlates of telicity
In this study we investigated whether the human brain distinguishes between telic events that necessarily entail a specified endpoint (e.g., reaching), and atelic events with no delimitation or final state (e.g., chasing). We used functional magnetic resonance imaging to explore the patterns of neural response associated with verbs denoting telic and atelic events, and found that the left posterior middle temporal gyrus (pMTG), an area consistently engaged by verb processing tasks, showed a significantly higher activation for telic compared with atelic verbs. These results provide the first evidence that the human brain appreciates whether events lead to an end or a change of state. Moreover, they provide an explanation for the long-debated question of which verb properties modulate neural activity in the left pMTG, as they indicate that, independently of any other semantic property, verb processing and event knowledge in this area are specifically related to the representation of telicity.
Domenica Romagno
Giuseppina Rota
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-10T13:02:15Z
2016-09-13T09:50:07Z
http://eprints.imtlucca.it/id/eprint/2879
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2879
2015-11-10T13:02:15Z
Emotional dysregulation in social anxiety insights from an fMRI resting-state study
The relationship between Social Phobia (SP) and subclinical social anxiety (SA), as well as with normal shyness is not completely defined. We used the Hurst Exponent (HE) to test the hypothesis that, even in a not socially anxious condition, relevant regions for the neurobiology of SP will display a relation between Social Anxiety levels as measured by psychological scales and HE of the BOLD signal. Resting-state fMRI time series were recorded in 26 subjects (12 F; mean age ± SD. = 26 ± 3). All the subjects were drug free and did notrefer any psychiatric disorder in the anamnesis. Each subject completed the following scales: Brief Fear of Negative Evaluation (BFNE), Interaction Anxiousness Scale (IAS), Liebowitz Social Anxiety scale (LSAS), Social Anxiety Spectrum Self-Report (SHI-SR) and State-Trait Anxiety Scale. The Hurst exponent was estimated by using the discrete second-order derivative approach and its relationship with SA has been tested in the whole brain and in regions known to be involved in SP. LSAS score predicted the HE in the anterior cingulate cortex (ACC), amygdala, cerebellum (all negatively) and precuneus (positively). ROI analysis showed an inverse correlation between LSAS and SHI-SR scores and HE in the amygdala and a direct correlation between IAS and BFNE scores in the precuneus. Our results suggest that the brain pattern of spontaneous activity is influenced by the degree of SA on a continuum in relevant regions for reappraisal and emotional regulation. We discuss our results in the framework of available knowledge on SA including the Clark ]";and Wells (1995) model of SA and the etiologic theories on emotional dysregulation in SA.
Claudio Gentili
Nicola Vanello
Ioana Cristea
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Daniel David
Pietro Pietrini
pietro.pietrini@imtlucca.it
Mario Guazzelli
2015-11-10T12:53:24Z
2017-08-04T10:19:22Z
http://eprints.imtlucca.it/id/eprint/2877
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2877
2015-11-10T12:53:24Z
It’s not all in your car: functional and structural correlates of exceptional driving skills in professional racers
Driving is a complex behavior that requires the integration of multiple cognitive functions. While many studies have investigated brain activity related to driving simulation under distinct conditions, little is known about the brain morphological and functional architecture in professional competitive driving, which requires exceptional motor and navigational skills. Here, 11 professional racing-car drivers and 11 “naïve” volunteers underwent both structural and functional brain magnetic resonance imaging (MRI) scans. Subjects were presented with short movies depicting a Formula One car racing in four different official circuits. Brain activity was assessed in terms of regional response, using an Inter-Subject Correlation (ISC) approach, and regional interactions by mean of functional connectivity. In addition, voxel-based morphometry (VBM) was used to identify specific structural differences between the two groups and potential interactions with functional differences detected by the ISC analysis. Relative to non-experienced drivers, professional drivers showed a more consistent recruitment of motor control and spatial navigation devoted areas, including premotor/motor cortex, striatum, anterior, and posterior cingulate cortex and retrosplenial cortex, precuneus, middle temporal cortex, and parahippocampus. Moreover, some of these brain regions, including the retrosplenial cortex, also had an increased gray matter density in professional car drivers. Furthermore, the retrosplenial cortex, which has been previously associated with the storage of observer-independent spatial maps, revealed a specific correlation with the individual driver's success in official competitions. These findings indicate that the brain functional and structural organization in highly trained racing-car drivers differs from that of subjects with an ordinary driving experience, suggesting that specific anatomo-functional changes may subtend the attainment of exceptional driving performance.
Giulio Bernardi
Luca Cecchetti
luca.cecchetti@imtlucca.it
Giacomo Handjaras
Lorenzo Sani
Anna Gaglianese
Riccardo Ceccarelli
Ferdinando Franzoni
Fabio Galetta
Gino Santoro
Rainer Goebel
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-10T12:03:08Z
2016-09-13T09:48:12Z
http://eprints.imtlucca.it/id/eprint/2874
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2874
2015-11-10T12:03:08Z
Cholinergic enhancement reduces functional connectivity and BOLD variability in visual extrastriate cortex during selective attention
Enhancing cholinergic function improves performance on various cognitive tasks and alters neural responses in task specific brain regions. We have hypothesized that the changes in neural activity observed during increased cholinergic function reflect an increase in neural efficiency that leads to improved task performance. The current study tested this hypothesis by assessing neural efficiency based on cholinergically-mediated effects on regional brain connectivity and BOLD signal variability. Nine subjects participated in a double-blind, placebo-controlled crossover fMRI study. Following an infusion of physostigmine (1 mg/h) or placebo, echo-planar imaging (EPI) was conducted as participants performed a selective attention task. During the task, two images comprised of superimposed pictures of faces and houses were presented. Subjects were instructed periodically to shift their attention from one stimulus component to the other and to perform a matching task using hand held response buttons. A control condition included phase-scrambled images of superimposed faces and houses that were presented in the same temporal and spatial manner as the attention task; participants were instructed to perform a matching task. Cholinergic enhancement improved performance during the selective attention task, with no change during the control task. Functional connectivity analyses showed that the strength of connectivity between ventral visual processing areas and task-related occipital, parietal and prefrontal regions reduced significantly during cholinergic enhancement, exclusively during the selective attention task. Physostigmine administration also reduced BOLD signal temporal variability relative to placebo throughout temporal and occipital visual processing areas, again during the selective attention task only. Together with the observed behavioral improvement, the decreases in connectivity strength throughout task-relevant regions and {BOLD} variability within stimulus processing regions support the hypothesis that cholinergic augmentation results in enhanced neural efficiency. This article is part of a Special Issue entitled ‘Cognitive Enhancers’.
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Giacomo Handjaras
Giulio Bernardi
Pietro Pietrini
pietro.pietrini@imtlucca.it
Maura L. Furey
2015-11-10T11:47:36Z
2016-09-13T09:46:12Z
http://eprints.imtlucca.it/id/eprint/2873
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2873
2015-11-10T11:47:36Z
Morphometric Changes of the Corpus Callosum in Congenital Blindness
We examined the effects of visual deprivation at birth on the development of the corpus callosum in a large group of congenitally blind individuals. We acquired high-resolution T1-weighted MRI scans in 28 congenitally blind and 28 normal sighted subjects matched for age and gender. There was no overall group effect of visual deprivation on the total surface area of the corpus callosum. However, subdividing the corpus callosum into five subdivisions revealed significant regional changes in its three most posterior parts. Compared to the sighted controls, congenitally blind individuals showed a 12 reduction in the splenium, and a 20 increase in the isthmus and the posterior part of the body. A shape analysis further revealed that the bending angle of the corpus callosum was more convex in congenitally blind compared to the sighted control subjects. The observed morphometric changes in the corpus callosum are in line with the well-described cross-modal functional and structural neuroplastic changes in congenital blindness.
Francesco Tomaiuolo
Serena Campana
D. Louis Collins
Vladimir S. Fonov
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Giuseppe Sartori
Pietro Pietrini
pietro.pietrini@imtlucca.it
Ron Kupers
Maurice Ptito
2015-11-10T11:38:27Z
2016-09-13T09:47:40Z
http://eprints.imtlucca.it/id/eprint/2869
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2869
2015-11-10T11:38:27Z
The effects of visual control and distance in modulating peripersonal spatial representation
In the presence of vision, finalized motor acts can trigger spatial remapping, i.e., reference frames transformations to allow for a better interaction with targets. However, it is yet unclear how the peripersonal space is encoded and remapped depending on the availability of visual feedback and on the target position within the individual’s reachable space, and which cerebral areas subserve such processes. Here, functional magnetic resonance imaging (fMRI) was used to examine neural activity while healthy young participants performed reach-to-grasp movements with and without visual feedback and at different distances of the target from the effector (near to the hand–about 15 cm from the starting position–vs. far from the hand–about 30 cm from the starting position). Brain response in the superior parietal lobule bilaterally, in the right dorsal premotor cortex, and in the anterior part of the right inferior parietal lobule was significantly greater during visually-guided grasping of targets located at the far distance compared to grasping of targets located near to the hand. In the absence of visual feedback, the inferior parietal lobule exhibited a greater activity during grasping of targets at the near compared to the far distance. Results suggest that in the presence of visual feedback, a visuo-motor circuit integrates visuo-motor information when targets are located farther away. Conversely in the absence of visual feedback, encoding of space may demand multisensory remapping processes, even in the case of more proximal targets.
Chiara Renzi
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Daniela Bonino
Giacomo Handjaras
Tomaso Vecchi
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-10T11:38:03Z
2016-09-13T09:45:43Z
http://eprints.imtlucca.it/id/eprint/2871
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2871
2015-11-10T11:38:03Z
The blind brain: How (lack of) vision shapes the morphological and functional architecture of the human brain
Since the early days, how we represent the world around us has been a matter of philosophical speculation. Over the last few decades, modern neuroscience, and specifically the development of methodologies for the structural and the functional exploration of the brain have made it possible to investigate old questions with an innovative approach. In this brief review, we discuss the main findings from a series of brain anatomical and functional studies conducted in sighted and congenitally blind individuals by our’s and others' laboratories. Historically, research on the ‘blind brain’ has focused mainly on the cross-modal plastic changes that follow sensory deprivation. More recently, a novel line of research has been developed to determine to what extent visual experience is truly required to achieve a representation of the surrounding environment. Overall, the results of these studies indicate that most of the brain fine morphological and functional architecture is programmed to develop and function independently from any visual experience. Distinct cortical areas are able to process information in a supramodal fashion, that is, independently from the sensory modality that carries that information to the brain. These observations strongly support the hypothesis of a modality-independent, i.e. more abstract, cortical organization, and may contribute to explain how congenitally blind individuals may interact efficiently with an external world that they have never seen.
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Giacomo Handjaras
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-10T11:34:54Z
2016-09-13T09:45:57Z
http://eprints.imtlucca.it/id/eprint/2870
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2870
2015-11-10T11:34:54Z
Modality Dependent Cross-Modal Functional Reorganization Following Congenital Visual Deprivation within Occipital Areas: A Meta-Analysis of Tactile and Auditory Studies
Cross-modal responses in occipital areas appear to be essential for sensory processing in visually deprived subjects. However, it is yet unclear whether this functional recruitment might be dependent on the sensory channel conveying the information. In order to characterize brain areas showing task-independent, but sensory specific, cross-modal responses in blind individuals, we pooled together distinct brain functional studies in a single based meta-analysis according only to the modality conveying experimental stimuli (auditory or tactile).Our approach revealed a specific functional cortical segregation according to the sensory modality conveying the non-visual information, irrespectively from the cognitive features of the tasks. In particular, dorsal and posterior subregions of occipital and superior parietal cortex showed a higher cross-modal recruitment across tactile tasks in blind as compared to sighted individuals. On the other hand, auditory stimuli activated more medial and ventral clusters within early visual areas, the lingual and inferior temporal cortex. These findings suggest a modality-specific functional modification of cross-modal responses within different portions of the occipital cortex of blind individuals. Cross-modal recruitment can thus be specifically influenced by the intrinsic features of sensory information.
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Leonardo Tozzi
Andrea Leo
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-10T11:31:09Z
2016-09-13T09:43:51Z
http://eprints.imtlucca.it/id/eprint/2868
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2868
2015-11-10T11:31:09Z
The direct, not V1-mediated, functional influence between the thalamus and middle temporal complex in the human brain is modulated by the speed of visual motion
Abstract The main visual pathway that conveys motion information to the middle temporal complex (hMT+) originates from the primary visual cortex (V1), which, in turn, receives spatial and temporal features of the perceived stimuli from the lateral geniculate nucleus (LGN). In addition, visual motion information reaches hMT+ directly from the thalamus, bypassing the V1, through a direct pathway. We aimed at elucidating whether this direct route between {LGN} and hMT+ represents a ‘fast lane’ reserved to high-speed motion, as proposed previously, or it is merely involved in processing motion information irrespective of speeds. We evaluated functional magnetic resonance imaging (fMRI) responses elicited by moving visual stimuli and applied connectivity analyses to investigate the effect of motion speed on the causal influence between {LGN} and hMT+, independent of V1, using the Conditional Granger Causality (CGC) in the presence of slow and fast visual stimuli. Our results showed that at least part of the visual motion information from {LGN} reaches hMT+, bypassing V1, in response to both slow and fast motion speeds of the perceived stimuli. We also investigated whether motion speeds have different effects on the connections between {LGN} and functional subdivisions within hMT+: direct connections between {LGN} and MT-proper carry mainly slow motion information, while connections between {LGN} and {MST} carry mainly fast motion information. The existence of a parallel pathway that connects the {LGN} directly to hMT+ in response to both slow and fast speeds may explain why {MT} and {MST} can still respond in the presence of {V1} lesions.
Anna Gaglianese
Mauro Costagli
Kenichi Ueno
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Giulio Bernardi
Pietro Pietrini
pietro.pietrini@imtlucca.it
Kang Cheng
2015-11-10T11:27:57Z
2016-09-13T09:47:52Z
http://eprints.imtlucca.it/id/eprint/2865
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2865
2015-11-10T11:27:57Z
Beyond motor scheme: a supramodal distributed representation in the action-observation network
The representation of actions within the action-observation network is thought to rely on a distributed functional organization. Furthermore, recent findings indicate that the action-observation network encodes not merely the observed motor act, but rather a representation that is independent from a specific sensory modality or sensory experience. In the present study, we wished to determine to what extent this distributed and ‘more abstract’ representation of action is truly supramodal, i.e. shares a common coding across sensory modalities. To this aim, a pattern recognition approach was employed to analyze neural responses in sighted and congenitally blind subjects during visual and/or auditory presentation of hand-made actions. Multivoxel pattern analyses-based classifiers discriminated action from non-action stimuli across sensory conditions (visual and auditory) and experimental groups (blind and sighted). Moreover, these classifiers labeled as ‘action’ the pattern of neural responses evoked during actual motor execution. Interestingly, discriminative information for the action/non action classification was located in a bilateral, but left-prevalent, network that strongly overlaps with brain regions known to form the action-observation network and the human mirror system. The ability to identify action features with a multivoxel pattern analyses-based classifier in both sighted and blind individuals and independently from the sensory modality conveying the stimuli clearly supports the hypothesis of a supramodal, distributed functional representation of actions, mainly within the action-observation network.
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Giacomo Handjaras
Daniela Bonino
Tomaso Vecchi
Luciano Fadiga
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-10T11:26:23Z
2016-09-13T09:45:30Z
http://eprints.imtlucca.it/id/eprint/2867
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2867
2015-11-10T11:26:23Z
Mind the blind brain to understand the sighted one! Is there a supramodal cortical functional architecture?
Abstract While most of the research in blind individuals classically has focused on the compensatory plastic rearrangements that follow loss of sight, novel behavioral, anatomical and functional brain studies in individuals born deprived of sight represent a powerful tool to understand to what extent the brain functional architecture is programmed to develop independently from any visual experience. Here we review work from our lab and others, conducted in sighted and congenitally blind individuals, whose results indicate that vision is not a mandatory prerequisite for the brain cortical organization to develop and function. Similar cortical networks subtend visual and/or non-visual perception of form, space and movement, as well as action recognition, both in sighted and in congenitally blind individuals. These findings support the hypothesis of a modality independent, supramodal cortical organization. Visual experience, however, does play a role in shaping specific cortical sub-regions, as loss of sight is accompanied also by cross-modal plastic phenomena. Altogether, studying the blind brain is opening our eyes on how the brain develops and works.
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Daniela Bonino
Silvia Pellegrini
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-10T11:22:29Z
2016-09-13T09:45:04Z
http://eprints.imtlucca.it/id/eprint/2866
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2866
2015-11-10T11:22:29Z
Local sleep in wakefulness and behavioral performance
Giulio Bernardi
Francesca Siclari
D. Dentico
X. Yu
Corinna Zennig
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
Giulio Tononi
2015-11-10T11:08:27Z
2016-09-13T09:45:17Z
http://eprints.imtlucca.it/id/eprint/2864
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2864
2015-11-10T11:08:27Z
Functional Signalers of Changes in Visual Stimuli: Cortical Responses to Increments and Decrements in Motion Coherence
How does our brain detect changes in a natural scene? While changes by increments of specific visual attributes, such as contrast or motion coherence, can be signaled by an increase in neuronal activity in early visual areas, like the primary visual cortex (V1) or the human middle temporal complex (hMT+), respectively, the mechanisms for signaling changes resulting from decrements in a stimulus attribute are largely unknown. We have discovered opposing patterns of cortical responses to changes in motion coherence: unlike areas hMT+, V3A and parieto-occipital complex (V6+) that respond to changes in the level of motion coherence monotonically, human areas V4 (hV4), V3B, and ventral occipital always respond positively to both transient increments and decrements. This pattern of responding always positively to stimulus changes can emerge in the presence of either coherence-selective neuron populations, or neurons that are not tuned to particular coherences but adapt to a particular coherence level in a stimulus-selective manner. Our findings provide evidence that these areas possess physiological properties suited for signaling increments and decrements in a stimulus and may form a part of cortical vigilance system for detecting salient changes in the environment.
Mauro Costagli
Kenichi Ueno
Pei Sun
Justin L. Gardner
Xiaohong Wan
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
Keiji Tanaka
Kang Cheng
2015-11-10T11:01:36Z
2016-09-13T09:44:33Z
http://eprints.imtlucca.it/id/eprint/2863
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2863
2015-11-10T11:01:36Z
A topographical organization for action representation in the human brain
How the human brain represents distinct motor features into a unique finalized action still remains undefined. Previous models proposed the distinct features of a motor act to be hierarchically organized in separated, but functionally interconnected, cortical areas. Here, we hypothesized that distinct patterns across a wide expanse of cortex may actually subserve a topographically organized coding of different categories of actions that represents, at a higher cognitive level and independently from the distinct motor features, the action and its final aim as a whole. Using functional magnetic resonance imaging and pattern classification approaches on the neural responses of 14 right-handed individuals passively watching short movies of hand-performed tool-mediated, transitive, and meaningful intransitive actions, we were able to discriminate with a high accuracy and characterize the category-specific response patterns. Actions are distinctively coded in distributed and overlapping neural responses within an action-selective network, comprising frontal, parietal, lateral occipital and ventrotemporal regions. This functional organization, that we named action topography, subserves a higher-level and more abstract representation of finalized actions and has the capacity to provide unique representations for multiple categories of actions. Hum Brain Mapp 36:3832–3844, 2015. © 2015 Wiley Periodicals, Inc.
Giacomo Handjaras
Giulio Bernardi
Francesca Benuzzi
Paolo Nichelli
Pietro Pietrini
pietro.pietrini@imtlucca.it
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
2015-11-10T10:57:50Z
2016-09-13T09:43:34Z
http://eprints.imtlucca.it/id/eprint/2862
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2862
2015-11-10T10:57:50Z
Spatial imagery relies on a sensory independent, though sensory sensitive, functional organization within the parietal cortex: A fMRI study of angle discrimination in sighted and congenitally blind individuals
Abstract Although vision offers distinctive information to space representation, individuals who lack vision since birth often show perceptual and representational skills comparable to those found in sighted individuals. However, congenitally blind individuals may result in impaired spatial analysis, when engaging in ‘visual’ spatial features (e.g., perspective or angle representation) or complex spatial mental abilities. In the present study, we measured behavioral and brain responses using functional magnetic resonance imaging in sighted and congenitally blind individuals during spatial imagery based on a modified version of the mental clock task (e.g., angle discrimination) and a simple recognition control condition, as conveyed across distinct sensory modalities: visual (sighted individuals only), tactile and auditory. Blind individuals were significantly less accurate during the auditory task, but comparable-to-sighted during the tactile task. As expected, both groups showed common neural activations in intraparietal and superior parietal regions across visual and non-visual spatial perception and imagery conditions, indicating the more abstract, sensory independent functional organization of these cortical areas, a property that we named supramodality. At the same time, however, comparisons in brain responses and functional connectivity patterns across experimental conditions demonstrated also a functional lateralization, in a way that correlated with the distinct behavioral performance in blind and sighted individuals. Specifically, blind individuals relied more on right parietal regions, mainly in the tactile and less in the auditory spatial processing. In sighted, spatial representation across modalities relied more on left parietal regions. In conclusions, intraparietal and superior parietal regions subserve supramodal spatial representations in sighted and congenitally blind individuals. Differences in their recruitment across non-visual spatial processing in sighted and blind individuals may be related to distinctive behavioral performance and/or mental strategies adopted when they deal with the same spatial representation as conveyed through different sensory modalities.
Daniela Bonino
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Giulio Bernardi
Lorenzo Sani
Claudio Gentili
Tomaso Vecchi
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-10T10:35:05Z
2016-09-13T09:44:05Z
http://eprints.imtlucca.it/id/eprint/2860
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2860
2015-11-10T10:35:05Z
Proneness to social anxiety modulates neural complexity in the absence of exposure: A resting state fMRI study using Hurst exponent
Abstract To test the hypothesis that brain activity is modulated by trait social anxiety, we measured the Hurst Exponent (HE), an index of complexity in time series, in healthy individuals at rest in the absence of any social trigger. Functional magnetic resonance imaging (fMRI) time series were recorded in 36 subjects at rest. All volunteers were healthy without any psychiatric, medical or neurological disorder. Subjects completed the Liebowitz Social Anxiety Scale (LSAS) and the Brief Fear of Negative Evaluation (BFNE) to assess social anxiety and thoughts in social contexts. We also obtained the fractional Amplitude of Low Frequency Fluctuations (fALFF) of the {BOLD} signal as an independent control measure for {HE} data. {BFNE} scores correlated positively with {HE} in the posterior cingulate/precuneus, while {LSAS} scores correlated positively with {HE} in the precuneus, in the inferior parietal sulci and in the parahippocamus. Results from fALFF were highly consistent with those obtained using {LSAS} and {BFNE} to predict HE. Overall our data indicate that spontaneous brain activity is influenced by the degree of social anxiety, on a continuum and in the absence of social stimuli. These findings suggest that social anxiety is a trait characteristic that shapes brain activity and predisposes to different reactions in social contexts.
Claudio Gentili
Nicola Vanello
Ioana Cristea
Daniel David
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Pietro Pietrini
pietro.pietrini@imtlucca.it
2015-11-10T10:32:22Z
2016-09-13T09:43:21Z
http://eprints.imtlucca.it/id/eprint/2859
This item is in the repository with the URL: http://eprints.imtlucca.it/id/eprint/2859
2015-11-10T10:32:22Z
Neural and Behavioral Correlates of Extended Training during Sleep Deprivation in Humans: Evidence for Local, Task-Specific Effects
Recent work has demonstrated that behavioral manipulations targeting specific cortical areas during prolonged wakefulness lead to a region-specific homeostatic increase in theta activity (5–9 Hz), suggesting that theta waves could represent transient neuronal OFF periods (local sleep). In awake rats, the occurrence of an OFF period in a brain area relevant for behavior results in performance errors. Here we investigated the potential relationship between local sleep events and negative behavioral outcomes in humans.Volunteers participated in two prolonged wakefulness experiments (24 h), each including 12 h of practice with either a driving simulation (DS) game or a battery of tasks based on executive functions (EFs). Multiple high-density EEG recordings were obtained during each experiment, both in quiet rest conditions and during execution of two behavioral tests, a response inhibition test and a motor test, aimed at assessing changes in impulse control and visuomotor performance, respectively. In addition, fMRI examinations obtained at 12 h intervals were used to investigate changes in inter-regional connectivity.The EF experiment was associated with a reduced efficiency in impulse control, whereas DS led to a relative impairment in visuomotor control. A specific spatial and temporal correlation was observed between EEG theta waves occurring in task-related areas and deterioration of behavioral performance. The fMRI connectivity analysis indicated that performance impairment might partially depend on a breakdown in connectivity determined by a “network overload.”Present results demonstrate the existence of an association between theta waves during wakefulness and performance errors and may contribute explaining behavioral impairments under conditions of sleep deprivation/restriction.
Giulio Bernardi
Francesca Siclari
Xiaoqian Yu
Corinna Zennig
Michele Bellesi
Emiliano Ricciardi
emiliano.ricciardi@imtlucca.it
Chiara Cirelli
Maria Felice Ghilardi
Pietro Pietrini
pietro.pietrini@imtlucca.it
Giulio Tononi