?url_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.au=Pietrini%2C+Pietro&rft.aulast=Pietrini&rft.aufirst=Pietro&rft.date=2004&rft.issn=0167-8760&rft.title=Cholinergic+enhancement+during+working+memory+improves+information+processing+in+the+human+brain%3A+effects+of+age+and+task+difficulty&rft.btitle=International+Journal+of+Psychophysiology&rft.genre=proceeding