Brain processing of visual sexual stimuli in human males

Despite its critical sociobiological importance, the brain processing of vi sual sexual stimuli has not been characterized precisely in human beings. W e used Positron Emission Tomography (PET) to investigate responses of regio nal cerebral blood flow (rCBF) in nine healthy males presented with visual sexual stimuli of graded intensity. Statistical Parametric Mapping was used to locate brain regions whose activation was associated with the presentat ion of the sexual stimuli and was correlated with markers of sexual arousal . The claustnum, a region whose function had been unclear, displayed one of the highest activations. Additionally, activations were recorded in parali mbic areas (anterior cingulate gyrus, orbitofrontal cortex), in the striatu m (head of caudate nucleus, putamen), and in the posterior hypothalamus. By contrast, decreased rCBF was observed in several temporal areas. Based on these results, we propose a model of the brain processes mediating the cogn itive, emotional, motivational, and autonomic components of human male sexu al arousal. Hum. Brain Mapping 11:162-277, 2000. (C) 2000 Wiley-Liss, Inc.