eprintid: 2874
rev_number: 7
eprint_status: archive
userid: 72
dir: disk0/00/00/28/74
datestamp: 2015-11-10 12:03:08
lastmod: 2016-09-13 09:48:12
status_changed: 2015-11-10 12:03:08
type: article
metadata_visibility: show
creators_name: Ricciardi, Emiliano
creators_name: Handjaras, Giacomo
creators_name: Bernardi, Giulio
creators_name: Pietrini, Pietro
creators_name: Furey, Maura L.
creators_id: emiliano.ricciardi@imtlucca.it
creators_id: 
creators_id: 
creators_id: pietro.pietrini@imtlucca.it
creators_id: 
title: Cholinergic enhancement reduces functional connectivity and BOLD variability in visual extrastriate cortex during selective attention
ispublished: pub
subjects: RC0321
divisions: CSA
full_text_status: none
keywords: Functional magnetic resonance imaging
abstract: 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’.
date: 2013-01
date_type: published
publication: Neuropharmacology
volume: 64
publisher: Elsevier
pagerange: 305 - 313
id_number: doi:10.1016/j.neuropharm.2012.07.003
refereed: TRUE
issn: 0028-3908
official_url: http://www.sciencedirect.com/science/article/pii/S0028390812003322
related_url_url: http://www.sciencedirect.com/science/article/pii/S0028390812003322
related_url_type: pub
citation:   Ricciardi, Emiliano and Handjaras, Giacomo and Bernardi, Giulio and Pietrini, Pietro and Furey, Maura L.  Cholinergic enhancement reduces functional connectivity and BOLD variability in visual extrastriate cortex during selective attention.  Neuropharmacology, 64.  305 - 313.  ISSN 0028-3908      (2013)