Handedness and approach-avoidance behavior in chimpanzees (Pan).

The relationship between hand preference and approach-avoidance behavior was examined in 49 chimpanzees (Pan). Ss were presented with 2 sets of novel objects on 4 consecutive days. The objects were presented for 2 hr during each session, and latency to touch any object was recorded for each S. Latency scores were then compared for chimpanzees that had been determined to be non-right- or right-handed. Right-handed Ss approached and touched the objects significantly faster than non-right-handed Ss did. In addition, males touched the objects significantly faster than did females. Correlations in approach-avoidance behavior were significant across stimulus sets and days of testing. The overall results support recent theoretical models linking hemispheric specialization with the expression of positive and negative affective behaviors.