ABSTRACT
Introduction Penile erection is initiated after central processing and integration of stimuli (e.g. tactile, visual, olfactory, and imaginative). Signals are generated to the peripheral tissues and the final response is mediated by co-ordinated spinal activity in the autonomic pathways (to the penis) and somatic pathways (to the perineal striated muscles). The central regulation of penile erection involves many transmitters and transmitter systems, the details of which are still not completely known. Some of the anatomical areas of the brain that relate to sexual function have been defined, including the medial amygdala, medial preoptic area (MPOA), paraventricular nucleus (PVN), periaqueductal gray, and ventral tegmentum. 1-3 In rats, electrical stimulation of the MPOA, 4 the PVN, 5 or the hippocampal formation 6 can elicit an erectile response.
