Long-Term Effects of Total Social Isolation Upon Behavior of Rhesus Monkeys

Abstract

8 isolate monkeys were compared in a follow-up study to 8 sophisticated controls in brief cross-sectional pairings with 12 stimulus strangers: 4 adults, 4 age-mates, and 4 juveniles. The isolates were characterized by infantile disturbance, less environmental orality, more fear, more aggression, less sex, less play, and bizarre ritualistic movements. 12-mo. isolates were fearful and nonaggressive but threatened many attacks. 6-mo. isolates were fearful and physically aggressive. The 12-mo. isolates demonstrated practically no positive social behavior. Conclusions are: (a) 6 mo. of social isolation during the first year has negative effects on social behavior up to puberty, (b) abnormal aggression appears in 3-yr.-old 6-mo. isolates, and (c) 12 mo. of isolation suppress or delay this aggression.

Child abuse and neglect: Usefulness of the animal data.

“…Separation from the mother and rearing in isolation resulted in extensive social pathology not limited to parenting. Motherless mothers and other socially deprived rhesus monkeys showed abnormalities in virtually every type of social interaction, including contact, proximity, grooming and play (Sackett, 1965), aggression and avoidance (Mitchell, Raymond, Ruppenthal, & Harlow, 1966), muting (Senko, 1966, as cited in Suomi, 1978), andcomlrmnication (Millel;Caul, & Mirsky, 1967). Therefore, early social deprivation provides, at best, a primate model for social pathology and not one specific to child abuse and neglect.…”

Social Recovery by Isolation-Reared Monkeys

“…While ethical considerations and practical constraints have obviously restricted controlled scientific study of isolation with human subjects, it has been possible to systematically investigate the effects of total social deprivation upon closely related, nonhuman, primate species. The unequivocal finding of numerous researches on macaque monkeys has been that total social isolation for at least the first 6 months of life enormously damages or destroys subsequent social and sexual behavioral capabilities (1)(2)(3). Monkeys so reared were grossly incompetent in interactions with socially normal age-mates.…”

Early social exposure in wild chimpanzees: Mothers with sons are more gregarious than mothers with daughters

“…Comparative research provides insight into the origins and development of sex differences in the absence of human cultural sex socialization. Decades of research in rodent and primate models have demonstrated that social deprivation curtails the development of species-appropriate behaviors (5)(6)(7)(8) and cognition (9,10). Primate mothers are critical for the normal social development of their infants (11)(12)(13), with classic studies demonstrating that maternal deprivation is associated with intense anxiety (14), inappropriate aggression (15), and an inability to form social relationships (16).…”