Behavioural and Electrophysiological Studies of Sleep and Animal Hypnosis

Abstract

EEG, EMG, and single cell activity were examined under states of animal hypnosis, sleep, and wakefulness. Rabbits and chickens were repetitively hypnotized to determine whether animal hypnosis was caused by a fear reaction. Differential susceptibility of chickens and rabbits to animal hypnosis suggests that more than a "paralysis of terror" is involved in causing this state. There was a difference in theta frequency in records from moving and still animals, and a 13-18 Hz component appeared on many records during synchronized and desynchronized sleep. A large number of cells fired with respect to certain EEG conditions rather than to a behavioural state. EEG and single cell activity obtained during early hypnosis were very similar to those appearing in an animal that was sitting alert.