The relationship of personality dimensions in adult male rhesus macaques to progression of simian immunodeficiency virus disease

Studies of nonhuman primate personality have suggested that physiological c orrelates of relevant behavioral dimensions exist. The present study examin ed personality using techniques similar to those employed in human personal ity research. Adult male rhesus monkeys were each rated on 25 adjectives wh ile living in their natal groups. Approximately 1.5 years later, 18 animals were inoculated with the simian immunodeficiency virus (SIV) and exposed t o socially stable or socially unstable conditions. Behavior, viral load (SN RNA), plasma cortisol concentrations, and the IgG response to SIV and to r hesus cytomegalovirus were measured at regular intervals, Multiple regressi on analyses revealed that the four personality dimensions (Sociability, Con fidence, Equability, Excitability) were correlated with various measures. F ollowing inoculation with SN, animals higher in Sociability showed a more r apid decline in plasma cortisol concentrations, elevations in the anti-RhCM V IgG response, and a decline in SIV RNA. The results indicate that persona lity factors in rhesus monkeys do hale physiological correlates that have s ignificance for disease processes and that in the context of a social manip ulation, Sociability, reflecting the tendency to engage in affiliative inte ractions, is an important factor in explaining outcome measures at early ti me points, (C) 1999 Academic Press.