Social preferences by and for pigtailed macaques (Macaca nemestrina) with trisomy 18

Social choices of trisomic macaques (macaca nemestrina) were compared with those of age-matched controls and of infants and adult females without handicaps. All groups chose social over nonsocial stimuli and showed few differences in their preferences for stimulus animals with and without handicaps. On initial encounter, the trisomic monkeys were socially interesting to age-matched controls and to younger animals and adult females. Thus, avoidance of individuals with handicaps probably is not a general primate trait. Even though the trisomic monkeys showed inappropriate social and motor behavior in play groups, their preference for social stimuli demonstrates that the presence of mental retardation and physical handicaps need not reduce positive social motivation even when prior social experiences have been largely negative.