Alterations in the nocturnal sleep cycle resulting from LSD

Certain neurophysiological similarities during LSD induced awake hallucinatory activity and “dreaming” sleep (REMS) are reviewed and the possible relationship of LSD neuropharmacological action to the hypothetical neurohumoral mechanism underlying REMS is considered.

Abstract

1. Thirty-six LSD doses of 0.08–0.73 μg/kg (6–40 μg total dose) were administered orally to humans either just prior to sleep or 1 h after onset of sleep. All night EEGs and EOGs were recorded on control nights, on nights when LSD was administered, and frequently on nights following those in which the drug was given. 2. On 21 nights following administration of LSD a prolongation of either the first or second REMS period was observed. Additional alterations were: (a) occurrence of brief REMS bursts interrupting phases of SWS; (b) general curtailment of REMS periods subsequent to a prolonged REMS period; (c) increased body movements and arousals frequently occurring in relation to REMS. 3. Certain neurophysiological similarities during LSD induced awake hallucinatory activity and "dreaming" sleep (REMS) are reviewed. The possible relationship of LSD neuropharmacological action to the hypothetical neurohumoral mechanism underlying REMS is considered.