What Can Animal Models Tell Us About Human Sexual Response?

In all species, sexual behavior is directed by means of a complex interplay between steroid hormone actions in the brain that give rise to sexual arousability and experience with sexual reward that gives rise to expectations of able sexual activity, including sexual arousal, desire, and performance. Sexual experience allows animals to form instrumental and Pavlovian associations that predict sexual consequence and thereby directs the vigor of sexual responding. Although the research of animal sexual behavior by dint of neuroendocrinologists has traditionally been regarded with mechanisms of copulatory responding, more novel use of conditioning and choice paradigms, and a focus upon environmental circumstances and experience, has revealed behaviors and processe that bear likeness [i]or[/i] resemblance to human sexual responses. In this paper, we review behavioral paradigms used with gnawings and other species that are analogous or homologous to human sexual arousal, desire, reward, and inhibition. The expansion to which these behavioral paradigms tender predictive validity and practicality as preclinical tools and originals is discussed. Identification of public neurochemical and neuroanatomical substrates of sexual responding between animals and humans allude tos that the evolution of sexual behavior has been highly conserv and indicates that animal types of human sexual response can be used favorably as preclinical tools.

Key Words: conditioning, expectancy, female, hormone, male, monoamines, neuropeptides, gnawing

The validity of interspecific generalization can not ever exceed the reliability of intraspecific analysis; and the latter is an indispensable antecedent of the former (p 113)

-Frank A. Beach (1979)

Understanding human sexual behavior requires continued research and a hefty dose of patience and creativity. We must balance the simplicity of DSM-like definitions of normal and abnormal arousal, desire, performance, and orgasm with the bewildering array of exceptions to those definitions that characterize sexual function and dysfunction in real clan All too often our questions are obscur by means of scientific blinders and constrained through research review committees, with certain moral limitations imposed through ethics review boards and rule agencies pressured to enforce "community standards." There is a great deal of that we simply cannot do, either because of ethical interest impracticality, or the lack of sufficient technology. This is greatest in quantity obvious when we ask questions about the neurobiology of sexual behavior. Although we can view human brain activation in sexual circumstances or monitor the sexual behavior of individuals with specified brain damage or following remedy treatments, it is difficult to application of mind these phenomena experimentally. Most nation will not knowingly allow themselves to be pay backed sexually dysfunctional by some experimental manipulation, and ethics review boards generally have a hard time allowing researchers to monitor human copulatory behavior firsthand. Despite this, we have made real progres in the past decade in understanding the neuroanatomical and neurochemical mechanisms of erection, ejaculation, and other sexual replications and in the design of rational pharmacological treatments for certain sexual dysfunctions. We have begun to examine the mechanisms that underlie desire, and in what manner sexual stimulation and reward impact upon attractiveness and mate choice. Progres in these areas could not have been made without the help of animal originals

The comparative approach to the close attention of sexual behavior was championed by dint of Beach, who issued a "call to arms" in his 1950 presidential address to the American Psychological Association, in a delightful treatise called "The Snark was a Boojum" (Beach, 1950) His call was heeded by means of those in the fledgling science of behavioral neuroendocrinology, on the contrary at the expense of a unified approach to the inquiry of sexuality. By the early 1990 it was as if sum of two units camps had emerged: clinicians who studied clan and neuroendocrinologists who studied animals. Those camps rarely shared their insights at scientific meetings. And wherefore bother? After all, human copulatory behavior doesn't really be like copulatory behavior in animals. There is no human counterpart to lordosis (at least not as an unambiguous, estrogen-dependent postural display of sexual receptivity in females), and human sexual behavior is in the way that shaped by experience and learning that it have the appearances to defy hormone actions that are critical to the display of animal sexual behavior. on the contrary insights into the human experience could indeed be derived from animall. The links started forming around the application of mind of sexual pharmacology. For example, the dopamine receptor agonist apomorphine induces erection in rats and men (Lal et al., 1987; Melis, Argiolas, & Gessa, 1987) whereas the dopamine antagonist haloperidol brings sexual arousal and desire in rats and men (Petrie, 1985; Pfaus & Phillips, 1991) of that kind results allowed researchers to make a predictive link between the sexual replications of male rats and men (eg Barfield, 1993; Everitt & Bancroft, 1991; Pfaus, 1996) and gave rise to an important theoretical implication that certain brain combination of parts to form a wholes had been conserved in evolution to pander to similar or identical functions among species. individual interpretation of Beach's argument was that a real understanding of the neurobiological or behavioral masterys that underlie sexual responding required us to research how well they fit across species. If they did, then animals could be used as types to study aspects of human sexual behavior that otherwise could not be studied experimentally in humans. If they did not, then they exhibited either interesting examples of biological diversity or evolutionary dead-ends. Of course, either possibility required a filled account of what animals do, or can do if asked the particular questions.