SLEEP · 1994 · 196 citations · 0 references
The present study investigated the hypnotic effects of 5 mg melatonin versus placebo when administered at 1200, 1700, 1900, and 2100 h. Eighteen young adults underwent a 7/13 ultrashort sleep‑wake paradigm after overnight sleep deprivation, receiving 5 mg melatonin in a double‑blind Latin‑square design. After each administration, melatonin significantly increased sleep propensity, theta, delta, and spindle spectral power, decreased alpha, beta, and oral temperature, and the latency to maximum effect shortened linearly from 3 h 40 min at 1200 h to 1 h at 2100 h, indicating a time‑dependent hypnotic effect that may reflect endogenous melatonin’s role in sleep‑wake regulation.
The present study investigated the hypnotic effects of 5 mg melatonin in comparison with placebo when administered at 1200,1700,1900 and 2100 hours. Eighteen young adults were studied with the 7/13 ultrashort sleep-wake paradigm after an overnight sleep deprivation. Melatonin was administered according to a double-blind Latin square design. After each administration, melatonin significantly increased sleep propensity, the spectral power in the theta, delta and spindles bands, and subjective sleepiness. It significantly decreased the power in the alpha and beta bands and oral temperature. The latency to maximum effect varied linearly from 3 hours 40 minutes at 1200 hours to 1 hour at 2100 hours. These findings indicate that melatonin possesses a time-dependent hypnotic effect and suggest that endogenous melatonin may participate in sleep-wake regulation.