AMYGDALOID HYPERSEXUALITY IN MALE CATS REEXAMINED

It is widely believed that amygdaloid lesions induce hypersexuality in certain mammals including humans. However, the evidence is so confused as to obscure the real nature of the purported changes. Twelve sexually experienced male cats were given two series of quantitative tests, the conventional sex test and a new selection test in which the animals were presented sequentially with a small stuffed toy panda, moving toy, tranquilized rabbit, tranquilized male and estrous female. Lesions in 8 experimental males were largely confined to the basolateral nuclei and periamygdaloid cortex. In the standard test and in the response to the female in the selection tests, the only significant postoperative change in the major measurements of sexual behavior was a decline in initial mount latency. However, in the selection tests, the major change was an increased tendency to mount less appropriate objects. There was no evidence of hypersexuality, in the sense of a higher level of sexual performance. This change was not interpreted as the disruption of an amygdaloid mechanism directly regulating sexual behavior, but rather as interference with a system which normally modulates approach and withdrawal behavior in response to stimuli that are salient with respect to an existing behavioral setting and set. © 1979.