The roots of sexual arousal and sexual orientation

Unlike members of other species that are genetically wired to be attracted to their sexual partners, humans learn the cues that guide them in choosing their sexual partners and that trigger sexual arousal. Genetically wired mechanisms must be directing the acquisition of those cues and organizing them in information structures that underlie human sexual behavior. Individual sexuality is a combination of the genetic mechanisms and information learned through personal experiences. This article focuses on the roots of human sexuality – on genetically embedded mechanisms, common to all humans, around which the wide variety of sexual behaviors is built. It proposes a model that defines the basic mechanisms and their role in developing individual sexuality. It is suggested that three brain areas host the roots of human sexuality: the auditory area, which provides stimuli that serve as cues for the identification of a mate; an emotional area, which provides cues for emotional arousal; and a corporal area, which controls the physiological expressions of arousal. The amygdala is a main candidate for the emotional area, and the hypothalamus for the corporal area, but other areas may also provide those inputs. Experimental observations that support this model are discussed, and an outline of additional experiments for validating the model is proposed. If validated, the model would provide knowledge that fills a gap in the understanding of human sexuality – knowledge that would benefit individuals, the medical profession, and society as a whole.