Auditory sensory memory impairment in Alzheimer's disease: an event-related potential study.
Auditory event-related potentials (ERP) were recorded from 10 healthy older subjects and 9 patients with Alzheimer's disease (AD) to investigate whether auditory sensory memory is impaired in AD. Standard (85%) and deviant (15%) tones were presented in random order with interstimulus intervals (ISI) of 1 s or 3 s in separate blocks. Deviant tones elicited a specific ERP component called mismatch negativity (MMN) which reflects automatic stimulus change detection and thus presumably, the neural basis of sensory memory in audition. The MMN amplitude decreased as a function of the ISI more in the AD group than in the control group. This suggests that the memory trace decays faster in the AD patients than in age-matched healthy controls.
Pekkonen
E
E
Department of Neurology, University Hospital of Kuopio, Finland.
Jousmäki
V
V
Könönen
M
M
Reinikainen
K
K
Partanen
J
J
D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000150:complications* / Q000523:psychology*; D000704:Analysis of Variance; D005072:Evoked Potentials, Auditory; D005260:Female; D006309:Hearing; D006801:Humans; D008297:Male; D008568:Memory / Q000502:physiology; D008569:Memory Disorders / Q000209:etiology* / Q000523:psychology*; D008875:Middle Aged; D009483:Neuropsychological Tests; D012016:Reference Values; D013997:Time Factors