Individual Differences in Long-term Cognitive Testing in a Group of Captive Chimpanzees

Abstract

Seven chimpanzees had participated in cognitive tasks from the time they were approximately 18 months to approximately 16 years of age when the data presented here was analyzed. Testing covered a wide range of tasks, which we categorized broadly as measuring their understanding of aspects of either their social or physical environments. Therefore, we could test whether individuals who excelled on ‘social’ tasks, also excelled on ‘physical’ tests. We also categorized our measures as ones of acquisition, criterion, retention or transfer of skill. Thus, we could determine whether individuals who mastered tasks quickly were also those who performed, remembered and generalized tasks most accurately. We were interested in whether there were consistent patterns in cognitive skills across tasks and measures. Results of our analyses indicate that, as with humans, chimpanzees vary in their performance across some measures, although some differences in cognitive skill between individuals are also consistent across measures and tasks. The results have implications for questions concerning domain generality or specificity of cognitive skills in another primate species.//