Sexual behavior in (human) adults

Abstract

It is with great interest and fascination that I listened to Dr. Pfaff’s talk and that I read his and Jessica Mong’s paper on “Hormonal and genetic influences underlying arousal as it drives sex and aggression in animal and human brains”. It is a nice example of the current scientific way of thinking in the field of molecular biology. How neural and genetic mechanisms are thought to be responsible for the expression of sexual arousal and even specific sociosexual behaviors. Or the absence of such an expression for instance in the case of Kallmann’s syndrome in the human male. Molecular biology has dramatically changed the old field of behavioral endocrinology, where the brain used to be more or less a ‘black box’. Science is rapidly unraveling the pathways through which hormones act on the neural tissues underlying sexual arousal and sexual behaviors. Once again, Dr. Pfaff’s presentation nicely illustrates this. As a discussant I would like to bring forward a few hopefully relevant topics, to start the general discussion with Dr. Pfaff. My main question is: how relevant are findings in rodents like mouse and rat for our understanding of human sexuality? Studying the molecular and genetic mechanisms underlying lordosis-behavior in the female rat, what could it teach us about human female sexual behavior? What would be the human equivalent of the lordosis behavior, or for that matter hopping and darting or increased locomotor behavior of the estrous female rat? Are similar estrogenic and progestagenic pathways assumed in the human female? What about lordosis behavior in male rats? We have ample experience in producing male rats, which in adulthood, without any hormone treatment, readily display ‘bisexual behaviors’ [2]. When paired with an estrous female rat these males mount, intromit and ejaculate. When paired with a sexually active male conspecific our males hop