INDUCTION OF BOTH EMOTIONAL BEHAVIOR AND A NOVEL FORM OF REM SLEEP BY CHEMICAL STIMULATION APPLIED TO CAT MESENCEPHALON

Carbachol injected into the midbrain close to the cerebral aqueduct produced emotional behavior followed by REM sleep from which arousal was impossible by sensory stimulation including surgical incision of the skin. Electrical stimulation applied at the same midbrain loci produced arousal from carbachol induced REM sleep. Injections of carbachol into sites further from the aqueduct elicited only emotional behavior. These findings are relevant to the hypothesis that drugs injected into the brain may act via diffusion into the ventricular system. © 1969.