Abstract # 72:

Scheduled for Thursday, August 18, 2005 07:00 PM-09:00 PM: (Cambridge/Oxford Room) Poster Presentation


R. M. Warren and G. P. Sackett
Washington Nat. Primate Research Center, University of Washington, BOX 357330, Seattle, WA 98195, USA
     We previously found that infant temperament measures tested by a familiar observer during a daily weighing procedure habituated over time, regressing toward a common mean with shrinking variability. This study aimed to determine if introduction of a very novel social probe stimulus would offset habituation and maintain earlier temperament differences throughout infancy. Daily weighing temperament measures (response to tester’s approach, presentation of diaper, removal from home cage, clinging on tester’s arm, reaction to weighing scale environment, defecate and/or urinate, irritability, consolability, and vocalizations) were collected from birth through 10 months on 5-32 infant pig-tailed macaques (Macaca nemestrina). This was done by a familiar tester four days each week, and on a probe test once each week by a familiar tester dressed in a novel costume (unfamiliar hats, masks, wigs, clothes, and shoes). Mean daily ratings were plotted by month for each category, with statistical significance (P ≤ 0.05) determined by non-overlapping standard errors. There were significant probe verses familiar differences on all categories. Approach, presentation of diaper, defecate/urinate, consolability, and vocalizations differed beginning at 5 months of age. Irritability differences appeared at 3 months, reaction to environment differences at 6 months. The probe tests did offset habituation and maintain large individual differences, but as in our past work early individual differences in temperament generally did not exhibit continuity over time. Supported by NIH grants RR00166 and HD023274.