I. Feinberg et al., Effects of hypnotics on the sleep EEG of healthy young adults: new data and psychopharmacologic implications, J PSYCH RES, 34(6), 2000, pp. 423-438
Benzodiazepine hypnotics increase NREM sleep and alter its EEG by reducing
delta (0.3-3 Hz) and increasing sigma (12-15 Hz) and beta (15-23 1-12) acti
vity. We tested whether the nonbenzodiazepine hypnotic, zolpidem (10 mg), p
roduced the same pattern of sleep and EEG changes as two "classical" benzod
iazepines, triazolam (0.25 mg) and temazepam (30 mg). Sleep EEG of 16 subje
cts was analyzed with period amplitude analysis for 3 nights during drug ad
ministration or placebo. The effects of zolpidem were in the same direction
but generally of smaller magnitude than those of the classical benzodiazep
ines. These differences are more likely the result of non-equivalent dosage
s than different pharmacologic actions. Period amplitude analysis showed th
at the decreased delta activity resulted mainly from a decrease in wave amp
litude. In contrast, the increased sigma and beta activity were produced by
increased wave incidence. Delta suppression increased with repeated drug a
dministration but sigma and beta stimulation did not. While these findings
have little relevance for the clinical choice of hypnotics they may hold im
portant implications for the brain mechanisms involved in hypnotic toleranc
e and withdrawal delirium. (C) 2001 Elsevier Science Ltd. All rights reserv
ed.