title: Differential brain processing of audiovisual sexual stimuli in men: comparative positron emission tomography study of the initiation and maintenance of penile erection during sexual arousal.
abstract: The human male psychosexual cycle consists of four phases: excitation, plateau, orgasm, and resolution. Identification of the specific neural substrates of each phase may provide information regarding the brain's pathophysiology of sexual dysfunction. We previously analyzed regional cerebral blood flow (rCBF) with H(2)15O-positron emission tomography (PET) during the excitation phase (initiation of penile erection) induced by audiovisual sexual stimuli (AVSS) and identified activation of the cerebellar vermis, the bilateral extrastriate cortex, and right orbitofrontal cortex, suggesting a role of cognition/emotion in the excitement phase. In the present study, we analyzed rCBF of the same six healthy volunteers during the plateau phase (maintenance of penile erection) induced by AVSS and compared the results with those of the excitation phase. Penile rigidity was monitored in real time with RigiScan Plus during PET scanning. Images were analyzed by statistical parametric mapping (SPM) software, and rCBF in the amygdala, hypothalamus, anterior cingulate, and insula was measured. During the plateau phase, primary subcortical activation was noted in the right ventral putamen, indicating motivational factors in the sexual response via the limbic reward circuit. A significant increase in rCBF in the left hypothalamus was also observed during the plateau phase. The right anterior cingulate and left insula were specifically activated during the excitation phase but not during the plateau phase. These results indicate a significant role of the ventral putamen and the hypothalamus in the plateau phase and confirm that paralimbic and limbic components of the human brain differentially coordinate the sexual response in a psychosexual phase-dependent manner.
authors.affiliation: Department of Urology, Osaka University Graduate School of Medicine, 2-2 Yamadaoka, Suita, Osaka, 565-0871, Japan.
authors.forename: Yasushi
authors.initials: Y
authors.lastname: Miyagawa
authors.forename: Akira
authors.initials: A
authors.lastname: Tsujimura
authors.forename: Kazutoshi
authors.initials: K
authors.lastname: Fujita
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Matsuoka
authors.forename: Tohru
authors.initials: T
authors.lastname: Takahashi
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Takao
authors.forename: Shingo
authors.initials: S
authors.lastname: Takada
authors.forename: Kiyomi
authors.initials: K
authors.lastname: Matsumiya
authors.forename: Yasuhiro
authors.initials: Y
authors.lastname: Osaki
authors.forename: Masashi
authors.initials: M
authors.lastname: Takasawa
authors.forename: Naohiko
authors.initials: N
authors.lastname: Oku
authors.forename: Jun
authors.initials: J
authors.lastname: Hatazawa
authors.forename: Shigeo
authors.initials: S
authors.lastname: Kaneko
authors.forename: Akihiko
authors.initials: A
authors.lastname: Okuyama
mesh_terms: D000328:Adult; D000465:Algorithms; D001921:Brain / Q000000981:diagnostic imaging* / Q000502:physiology*; D001931:Brain Mapping; D003627:Data Interpretation, Statistical; D004644:Emotions / Q000502:physiology; D007839:Functional Laterality / Q000502:physiology; D006801:Humans; D007031:Hypothalamus / Q000502:physiology; D007989:Libido / Q000502:physiology*; D008297:Male; D015233:Models, Statistical; D009042:Motivation; D010410:Penile Erection / Q000502:physiology*; D010775:Photic Stimulation; D049268:Positron-Emission Tomography; D011699:Putamen / Q000502:physiology; D012725:Sexual Behavior / Q000502:physiology*; D013238:Stereotaxic Techniques