title: Face short-term memory-related electroencephalographic patterns can differentiate multi- versus single-domain amnestic mild cognitive impairment.
abstract: Amnestic mild cognitive impairment (aMCI) is characterized by memory deficits alone (single-domain, sd-aMCI) or associated with other cognitive disabilities (multi-domain, md-aMCI). The present study assessed the patterns of electroencephalographic (EEG) activity during the encoding and retrieval phases of short-term memory in these two aMCI subtypes, to identify potential functional differences according to the neuropsychological profile. Continuous EEG was recorded in 43 aMCI patients, whose 16 sd-aMCI and 27 md-aMCI, and 36 age-matched controls (EC) during delayed match-to-sample tasks for face and letter stimuli. At encoding, attended stimuli elicited parietal alpha (8-12 Hz) power decrease (desynchronization), whereas distracting stimuli were associated with alpha power increase (synchronization) over right central sites. No difference was observed in parietal alpha desynchronization among the three groups. For attended faces, the alpha synchronization underlying suppression of distracting letters was reduced in both aMCI subgroups, but more severely in md-aMCI cases that differed significantly from EC. At retrieval, the early N250r recognition effect was significantly reduced for faces in md-aMCI as compared to both sd-aMCI and EC. The results suggest a differential alteration of working memory cerebral processes for faces in the two aMCI subtypes, face covert recognition processes being specifically altered in md-aMCI.
authors.affiliation: INSERM U1039, Faculty of Medicine, La Tronche, France. Marie.P.DeiberIbanez@hcuge.ch
authors.forename: Marie-Pierre
authors.initials: MP
authors.lastname: Deiber
authors.forename: Vicente
authors.initials: V
authors.lastname: Ibáñez
authors.forename: François
authors.initials: F
authors.lastname: Herrmann
authors.forename: Cristelle
authors.initials: C
authors.lastname: Rodriguez
authors.forename: Joan
authors.initials: J
authors.lastname: Emch
authors.forename: Pascal
authors.initials: P
authors.lastname: Missonnier
authors.forename: Philippe
authors.initials: P
authors.lastname: Millet
authors.forename: Gabriel
authors.initials: G
authors.lastname: Gold
authors.forename: Panteleimon
authors.initials: P
authors.lastname: Giannakopoulos
mesh_terms: D000203:Activities of Daily Living; D000368:Aged; D000647:Amnesia / Q000150:complications / Q000175:diagnosis* / Q000523:psychology; D000704:Analysis of Variance; D016022:Case-Control Studies; D060825:Cognitive Dysfunction / Q000150:complications / Q000175:diagnosis* / Q000523:psychology; D004569:Electroencephalography / Q000379:methods; D005074:Evoked Potentials, Visual / Q000502:physiology*; D005145:Face; D005260:Female; D006801:Humans; D008297:Male; D008570:Memory, Short-Term / Q000502:physiology*; D008609:Mental Status Schedule; D008875:Middle Aged; D010364:Pattern Recognition, Visual / Q000502:physiology*; D010775:Photic Stimulation; D011930:Reaction Time / Q000502:physiology; D013997:Time Factors