Effects of chronically administered antidepressant drugs on animal behavior

We reviewed the literature about the effects of chronically administered antidepressant drugs on animal drive-related behaviors that are increased by platform REM Sleep Deprivation (RSD): intracranial self-stimulation, locomotion, aggression, feeding, grooming and sex. We found no previous review of behavioral effects of chronic antidepressant drugs; about 200 papers on behavioral effects of one dose of antidepressant drugs; and only 14 papers on behavioral effects of chronically administered antidepressant drugs. With one dose, antidepressant drugs usually did not increase animal behaviors. With chronic administration, antidepressant drugs increased intracranial self-stimulation, locomotion, and affective aggression. Chronic drug effects on feeding, grooming, and sex were not studied. These findings are consistent with the hypothesis that antidepressant drugs increase animal drive-related behaviors by RSD because RSD precedes tested behavior with chronic drug administration but not with one dose. The findings, plus a critical review of RSD by pendulum and by midbrain stimulation, support the hypotheses (1) that in animals all methods of RSD increase drive-related behaviors; and (2) that in humans antidepressant drugs improve depression by RSD which enhances such behaviors.