Some observations on psychosocial stressors, immunity, and individual differences in nonhuman primates.

Many studies would appear to support an important relationship between behavior and the regulation of the immune response, at the core of the developing field of psychoneuroimmunology (PNI). However, wide variations are noted in the strength of this relationship, even for the same species under very similar circumstances. The present paper reviews work from our laboratory in both young and adult pigtail and bonnet macaques describing the ranges of variability in both behavioral and immunological responses to social separation and social conflict. It is shown that the magnitude of immune changes that follow a social stressor often covary with the magnitude of the behavioral changes that are observed. Second, there is support for the observation that there are specific behaviors such as social affiliation that may mitigate untoward behavioral and immunological consequences of social stressors. Finally, studies are reviewed which suggest that assessment of autonomic reactivity as reflected in cardiovascular regulation might provide an important clue to the relative risk for immune modulation under challenge. © 1996 Wiley-Liss, Inc.