Sex Differences Can Influence Behavioral Responses

In both animal experimentation and clinical medicine the impacts of sex differences on hormone/behavior relations are very obvious and pervasive. In animals and human beings the most obvious neuroendocrine sex difference is the ability of the female to demonstrate an ovulatory surge of luteinizing hormone whereas the male cannot. In mammalian animals the same schedule of estrogen priming followed by progesterone amplification leads to female-typical courtship behaviors followed by lordosis behavior in the female, but not in the male. Long-term testosterone treatment of laboratory animals leads to intromission and ejaculation in the male but not in the female, even though simple mounting behavior might be exhibited by both sexes. Organizational effects are exerted early in life, during brain development, and affect later responses to stimuli and hormones in adulthood. Activational effects are exerted in adulthood and more directly facilitate or repress specific classes of behaviors in animals and humans. As a result, genetic sex and social gender roles are usually consonant.