Neuroanatomical correlates of visually evoked sexual arousal in human males.

Brain areas activated in human male sexual behavior have not been character ized precisely. For the first time, positron emission tomography (PET) was used to identify, the brain areas activated in healthy males experiencing v isually evoked sexual arousal. Eight male subjects underwent six measuremen ts of regional brain activity following the administration of [O-15]H2O as they viewed three categories of film clips: sexually explicit clips, emotio nally neutral control clips, and humorous control clips inducing positive b ut nonsexual emotions. Statistical Parametric Mapping was used to identify brain regions demonstrating apr increased activity associated with the sexu al response to the visual stimulus. Visually evoked sexual arousal was char acterized by a threefold pattern of activation: the bilateral activation of the inferior temporal cortex, a visual association area the activation of the right insula and right inferior frontal cortex, which art! two paralimb ic areas relating highly processed sensory information with motivational st ates; and the activation of the left anterior cingulate cortex another para limbic area known to control autonomic and neuroendocrine functions. Activa tion of some of these areas was positively correlated with plasma testoster one levels. Although this study should be considered preliminary, it identi fied brain regions whose activation was correlated with visually evoked sex ual arousal in males.