Abstract

The development, expression, and extinction of a novel conditioned sexual behavior, conditioned ejaculatory preference (CEP), were studied. Male rats allowed to copulate with sexually-receptive females bearing an artificial odor (almond or lemon) displayed a subsequent preference for a female bearing that odor over a female that did not. Males receiving explicitly-unpaired or randomly-paired training failed to display this preference, implicating classical conditioning mechanisms in the development of this behavior. Examination of the time course of the development of CEP found that it develops rapidly, demonstrating the importance of early sexual experience in the determination of sexual partner preferences. Extinction occurred during copulation tests with one scented and one unscented female. Further, the rate of extinction was faster following massed training than distributed training. Analysis of the components of copulation required to support the development of CEP revealed that ejaculation was necessary, but not sufficient to support CEP. Rather CEP development is critically dependent upon the presence of a scented female during the postejaculatory period. Finally, the nature of the conditioned response mediating CEP was shown to be a bias of copulatory responses toward the scented female near the point of ejaculation, not facilitated ejaculation per se . The present findings are interpreted in Pavlovian and incentive motivational models to provide a framework for understanding the role of learning in sexual partner preference.