Social isolation and other behavioral changes in groups of adult vervet monkeys (Cercopithecus aethiops) produced by low, nonchronic doses of d-amphetamine.

Doses (0.1--0.7 mg/kg body weight) d-amphetamine were administered to three independent groups of green vervet monkeys (Cerecopithecus aethiops). Each group formed a triad with one male and two females. Amphetamine changed both the individual and the social behavior patterns significantly. Stereotypy and social isolation (withdrawal) were characteristic features of the amphetaminized animals. Also stereotyped social grooming was observed. The results are discussed in relation to behavior changes seen in amphetamine psychoses and in naturally occurring endogenous psychoses. It is emphasized that the study of patterns of behavior is an important object of research and relevant line in future investigations on psychopathology.