The temporal neocortex was removed in 4 monkeys, and 5 received amygdala destruction. Four control animals received skin and muscle incisions. The monkeys were compared on a visual pattern discrimination task, a food-non-food discrimination, and a rating scale that measured agonistic and approach behavior. Only the cortical lesion disrupted retention of the visual pattern task and neither lesion disrupted performance of the food-non-food task. Both lesions produced oral behavior, increased reaction to stimuli and decreased emotionality. Thus, the major symptoms of the Klüver-Bucy syndrome are produced by destroying either the temporal neocortex or the amygdala.