Acute nicotine effects on auditory sensory memory in tacrine-treated and nontreated patients with Alzheimer's disease: an event-related potential study.
The auditory mismatch negativity (MMN) event-related brain potential (ERP) reflects the storage of information in acoustic sensory memory. Thirteen patients with Alzheimer's disease (AD), 6 receiving treatment with the cholinesterase inhibitor, tacrine [tetrahydroaminoacridine (THA)], and 7 receiving no treatment, were administered 2 mg of nicotine polacrilex and placebo. MMNs were recorded with 1- and 3-s interstimulus intervals (ISIs) during pre- and post-placebo/nicotine administration. Amplitudes decreased from pre- to post-placebo recordings in nontreated patients but remained stable in THA-treated patients. Comparison of pre- and post-nicotine MMNs found amplitude increases with nicotine in nontreated but not in THA-treated patients. MMN latencies were shortened by nicotine in both treatment groups. These exploratory findings suggest that nicotine-improved strength of acoustic sensory memory traces and speed of acoustic sensory discrimination in AD are differentially affected by chronic tacrine treatment.
Engeland
C
C
Department of Psychiatry and Psychology, University of Western Ontario, London, ON, Canada.
Mahoney
C
C
Mohr
E
E
Ilivitsky
V
V
Knott
Verner J
VJ
D000161:Acoustic Stimulation / Q000379:methods; D000368:Aged; D000369:Aged, 80 and over; D000544:Alzheimer Disease / Q000188:drug therapy* / Q000503:physiopathology / Q000523:psychology; D000704:Analysis of Variance; D018592:Cross-Over Studies; D004311:Double-Blind Method; D005072:Evoked Potentials, Auditory / Q000187:drug effects* / Q000502:physiology; D005260:Female; D006801:Humans; D008297:Male; D008568:Memory / Q000187:drug effects* / Q000502:physiology; D008875:Middle Aged; D009538:Nicotine / Q000008:administration & dosage*; D013619:Tacrine / Q000627:therapeutic use*
D013619:Tacrine; D009538:Nicotine