Serotonin and behavior: emphasis on motor control.

Electrophysiologic studies of brain serotonergic neurons in behaving animals indicate that their activity is closely related to the sleep-wake-arousal cycle and to certain specific types of repetitive motor activity. A variety of other environmental and physiologic manipulations are ineffective in altering the activity of this neurochemical system. An attempt is made to relate these results to well-known involvement of brain serotonin in human affective disorders.