Neural mediation of mating in male cats: I. Effects of unilateral and bilateral removal of the neocortex.

Abstract

Adult male cats brought into the laboratory did not mate readily with receptive females in initial tests, but following a "conditioning" procedure they copulated consistently and reliably. The number of intromissions per 60-minutes test was the most reliable indicator of mating performance. Normal male cats mounted on the average 89 times, and achieved intromission 5.3 times per hour test. Unilateral removal of the neocortex in 5 of these males had the following effects upon coital activity: (a) increase in the latency of mating, (b) decrease in the frequency of mounting and intromission responses, (c) marked increase in the frequency of grips not followed by mounting, (d) no change in the percentage of mounts resulting in intromission, (e) occasional motor abnormalities such as forced circling, and (f) no detectable diminution of responsiveness to sexual stimuli. Bilateral removal of the neocortex in male cats abolished all sexual behavior except for some vocalization. This result was probably not due to androgenic deficiency, since testes appeared histoiogically normal and since androgen administration had no effect upon decorticated males.