Abstract # 182:

Scheduled for Sunday, September 18, 2011 07:00 PM-09:00 PM: Session 23 (Salon G (Sixth Floor)) Poster Presentation


EFFECT OF MOTHER'S DOMINANCE RANK ON OFFSPRING TEMPERAMENT IN INFANT RHESUS MONKEYS (MACACA MULATTA)

B. Suarez-Jimenez1, A. Hathaway1, C. Waters1, K. Vaughan1, S. J. Suomi2, P. Noble1 and E. Nelson1
1NIH/NIMH, 9000 Rockville Pike, Bethesda, MD, USA, 2NIH/NICHD
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Individual differences in temperament have been consistently observed in human infants. Several recent studies have also reported temperamental differences in infant rhesus monkeys. While heredity is thought to contribute substantially to temperament, so too are environmental factors such as social context and parenting. In the current study we assessed the contribution of maternal dominance rank to the expression of inhibited temperament in infant rhesus monkeys. Temperament was assessed in 26 infants at both 3 and 6 months of age with a battery that included human intruder test, human intruder-startle, and observations of interactions with the mother. Throughout testing infants lived with their mothers and a small group of other monkeys in indoor outdoor runs. Dominance rank of the mothers within each run was rated as either low/middle (n=18) or high (n=8). Maternal dominance rank interacted with tests such that infants of high ranking mothers displayed a greater context modulation of aggressive behavior and startle. High ranking infants displayed greater inhibition of startle and more aggression directed at the intruder in the stare condition; and spent more time away from mothers (all p<.05) in the interaction tests. These findings suggest that dominance of the mother may influence behavioral reactivity of infants. It is unclear whether this pattern is a result of heredity or parenting style though an interaction of these seems most likely.