title: EEG power spectra and cognitive change in geriatric psychiatry: a longitudinal study.
abstract: Elderly patients with senile dementia of the Alzheimer type (SDAT), multi-infarct dementia (MID) and functional psychiatric illness, along with elderly control subjects, were studied longitudinally at 6 monthly intervals over a 2 year period, with cognitive testing and EEG power spectral analyses being carried out on each occasion. There was no significant change in the EEG power over time although a significant regression effect was noted for cognitive performance in the SDAT group. A number of between-group differences were apparent. The SDAT patients had more delta and theta power and less alpha power than those with MID and the latter group had a higher percentage of delta and theta power than the functional patients. The functional patients and normal subjects were differentiated from each other by a number of EEG power variables. The implications of these findings with respect to differential diagnosis in geriatric psychiatry are discussed.
authors.affiliation: Department of Psychiatry, Ninewells Hospital and Medical School, Dundee, Scotland, UK.
authors.forename: E P
authors.initials: EP
authors.lastname: Sloan
authors.forename: G W
authors.initials: GW
authors.lastname: Fenton
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000503:physiopathology*; D000704:Analysis of Variance; D001921:Brain / Q000503:physiopathology*; D003071:Cognition / Q000502:physiology*; D015161:Dementia, Multi-Infarct / Q000503:physiopathology*; D004569:Electroencephalography; D006801:Humans; D001523:Mental Disorders / Q000503:physiopathology*; D011581:Psychological Tests; D012815:Signal Processing, Computer-Assisted