Abstract # 106:

Scheduled for Friday, June 20, 2008 05:00 PM-07:00 PM: Session 12 (Ball Rooms A and B) Poster Presentation

The relationship between cortisol and behavioral indicators of stress during cognitive computerized testing in chimpanzees (PAN TROGLODYTES)

M. R. Heintz1 and L. A. Parr2,3
1University of Chicago, Chicago, IL 60637, USA, 2Yerkes National Primate Research Center, 3Division of Psychiatry and Behavioral Sciences, Emory University
     Laboratories utilize computerized testing procedures to understand cognition in chimpanzees. Subjects willingly perform tasks which often appear to reduce boredom; however, subjects may also display behaviors indicating stress after selecting incorrect answers. We investigated if the difficulty or reward fairness during cognitive tasks correlated with behavioral frustration and salivary cortisol in six captive, nursery-reared chimpanzees (four males & two females, 11-18 yrs of age). Three match to sample (MTS) tasks were administered lasting 15 minutes each. An easy MTS task consisted of matching identical clipart images. A hard MTS task, similar to the Wisconsin Card Sorting Task, consisted of reward contingencies that could change. In the no reward condition, identical to the easy task, the cagemate, not the subject, received the rewards. Testing occurred at the same time each day. Saliva was collected immediately before each test session, immediately after completion of the test session, and 10 and 45 minutes after completion of the test. Testing was video recorded and behavior was scored for frequency of arousal behavior. Results showed a near-significant trend for higher rates of rough scratching in the no reward condition, indicating greater stress and arousal, compared to the easy task [t-test; a=0.05]. However, no significant correlation between testing condition and salivary cortisol was found when tested with a mixed model to account for repeated measures on subjects [a=0.05]. This study suggests that behavioral frustration and cortisol can become dissociated.