Abstract # 175:

Scheduled for Sunday, September 14, 2014 07:00 PM-09:00 PM: Session 22 (Decatur B) Poster Presentation


BEHAVIORAL RESPONSES TO CAGEMATE STRESS ARE INDEPENDENT OF SOCIAL RANK AND PREDICT CORTISOL OUTPUT IN GROUP-HOUSED FEMALE RHESUS MACAQUES (MACACA MULATTA).

J. N. Kohn1,2, Z. P. Johnson1, D. Toufexis3 and M. E. Wilson1
1Yerkes National Primate Research Center, Division of Developmental and Cognitive Neuroscience, 954 Gatewood Rd, Atlanta, GA 30329, USA, 2Emory University, Graduate Program in Neuroscience, 3Department of Psychology, University of Vermont, Burlington, VT
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     Studies of socially housed rhesus macaques indicate that social partners ameliorate the neuroendocrine response to acute stressors, though relatively little is known about the specific behaviors that buffer the stress response and whether buffering differs by social rank. To address this question, we exposed adult female rhesus macaques (n = 20) of the highest and lowest rank within their respective social groups to human intruder stress (20 min) and recorded group-wide behaviors immediately following reintroduction. In order to assess cortisol dynamics, serum cortisol was measured at baseline, 30 min, and 4 hr following stressor onset. Compared to non-testing days, cagemate removal, stress, and reintroduction significantly increased affiliative behavior within the group [F(3, 30) = 6.45, p = 0.017], independent of the stressed cagemate’s social rank. Neither total cortisol output [t(18) = -1.22, p = 0.239] nor cortisol recovery [F(1,20) = 1.98, p=0.176] differed by rank; however, the frequency of anxiety-like behaviors emitted by stressed subjects predicted their own cortisol output [B = 0.53, p = 0.015]. Rank was not a significant predictor [B = 0.26, p = 0.20]; overall model fit was R^2 = 0.353. These results suggest that group housed adult female rhesus macaques increase prosocial behavior following cagemate stress, but that individual temperament, rather than group behavior, modulates the neuroendocrine response to acute psychosocial stressors. Support: NIH Grants MH081816 and P51OD011132.