Abstract # 82:

Scheduled for Friday, June 20, 2008 04:45 PM-04:55 PM: Session 10 (Meeting Room 1GHI) Oral Presentation

Long-term HPA Profile Predicts Object Permanence Performance in Infant Rhesus Macaques (Macaca mulatta)

A. M. Dettmer1, M. F. S. X. Novak2, S. J. Suomi2 and M. A. Novak1
1Neuroscience & Behavior Program, University of Massachusetts, Amherst, MA 01003, USA, 2Laboratory of Comparative Ethology, National Institutes of Health (NICHD), Poolesville, MD, 20837, USA
     Lower plasma cortisol levels have been linked to superior cognitive performance in juvenile and adult monkeys. However, there is no information on whether this same relationship is present in infant primates. Moreover, previous studies have relied on “point” samples of HPA activity and have not determined whether long-term cortisol concentrations predict cognitive performance. To test the hypothesis that cognitive performance in infants can be predicted by long-term cortisol concentrations, we studied 17 nursery-reared rhesus monkeys on four stages of object permanence in the first few months of life and analyzed hair samples collected at 6 months for their cortisol content. Linear regression revealed that infants with lower hair cortisol reached criterion at an earlier age and in fewer sessions on the well [multiple R; R=0.57;n=17;p<0.05; R=0.61;n=17;p=0.01 respectively] and screen [R=0.54;n=17;p<0.05; R=0.59;n=17;p=0.01 respectively] tasks. A similar trend was observed for age at criterion in the A-not-B task [R=0.42;n=17;p<0.10]. Baseline salivary cortisol obtained at day 30 did not predict performance on any of the tasks. This study is the first to use a long-term measure of HPA profile to predict infant monkey cognitive performance. The results are consistent with previous findings in older monkeys correlating lower plasma cortisol with enhanced cognitive performance, and they further suggest that long-term HPA measures may better predict cognitive abilities than conventional short-term measures under some experimental conditions.