Development of social behavior in an adult total isolate rhesus monkey (Macaca mulatta).

A 12-year-old female total isolate rhesus monkey was pretested with age mates and subsequently housed for 20 weeks with an infant "therapist" monkey. Daily observations during that period revealed a 24-fold increase in the probability of social behavior. Self-directed behaviors also increased significantly. Disturbance behaviors (self-slapping, self-biting, bizarre limb movements, etc.) remained unchanged. Although problems obviously exist in cross-species generalization, and are here considered, these results emphasize the importance of early therapeutic intervention as well as the need for a more comprehensive approach to both social and disturbance behaviors if the treatment of adults is to be as successful as the treatment of immature isolate subjects.