title: Regional cerebral blood flow changes associated with clitorally induced orgasm in healthy women.
abstract: There is a severe lack of knowledge regarding the brain regions involved in human sexual performance in general, and female orgasm in particular. We used [15O]-H2O positron emission tomography to measure regional cerebral blood flow (rCBF) in 12 healthy women during a nonsexual resting state, clitorally induced orgasm, sexual clitoral stimulation (sexual arousal control) and imitation of orgasm (motor output control). Extracerebral markers of sexual performance and orgasm were rectal pressure variability (RPstd) and perceived level of sexual arousal (PSA). Sexual stimulation of the clitoris (compared to rest) significantly increased rCBF in the left secondary and right dorsal primary somatosensory cortex, providing the first account of neocortical processing of sexual clitoral information. In contrast, orgasm was mainly associated with profound rCBF decreases in the neocortex when compared with the control conditions (clitoral stimulation and imitation of orgasm), particularly in the left lateral orbitofrontal cortex, inferior temporal gyrus and anterior temporal pole. Significant positive correlations were found between RPstd and rCBF in the left deep cerebellar nuclei, and between PSA and rCBF in the ventral midbrain and right caudate nucleus. We propose that decreased blood flow in the left lateral orbitofrontal cortex signifies behavioural disinhibition during orgasm in women, and that deactivation of the temporal lobe is directly related to high sexual arousal. In addition, the deep cerebellar nuclei may be involved in orgasm-specific muscle contractions while the involvement of the ventral midbrain and right caudate nucleus suggests a role for dopamine in female sexual arousal and orgasm.
authors.affiliation: Department of Anatomy and Embryology, University Medical Center Groningen, University of Groningen, Antonius Deusinglaan 1, bldg 3215 room 729, 9713 AV Groningen, the Netherlands. j.r.georgiadis@med.umcg.nl
authors.forename: Janniko R
authors.initials: JR
authors.lastname: Georgiadis
authors.forename: Rudie
authors.initials: R
authors.lastname: Kortekaas
authors.forename: Rutger
authors.initials: R
authors.lastname: Kuipers
authors.forename: Arie
authors.initials: A
authors.lastname: Nieuwenburg
authors.forename: Jan
authors.initials: J
authors.lastname: Pruim
authors.forename: A A T Simone
authors.initials: AA
authors.lastname: Reinders
authors.forename: Gert
authors.initials: G
authors.lastname: Holstege
mesh_terms: D000328:Adult; D001143:Arousal / Q000502:physiology; D001921:Brain / Q000098:blood supply / Q000000981:diagnostic imaging / Q000502:physiology*; D001931:Brain Mapping; D002529:Cerebellar Nuclei / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000502:physiology; D002560:Cerebrovascular Circulation / Q000502:physiology*; D002987:Clitoris / Q000294:innervation / Q000502:physiology*; D003307:Copulation / Q000502:physiology; D015536:Down-Regulation / Q000502:physiology; D005260:Female; D007839:Functional Laterality / Q000502:physiology*; D006801:Humans; D008875:Middle Aged; D009433:Neural Inhibition / Q000502:physiology; D009434:Neural Pathways / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000502:physiology*; D009948:Orgasm / Q000502:physiology*; D017773:Pelvic Floor / Q000294:innervation / Q000502:physiology; D010812:Physical Stimulation; D049268:Positron-Emission Tomography; D017397:Prefrontal Cortex / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000502:physiology; D013003:Somatosensory Cortex / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000502:physiology; D013702:Temporal Lobe / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000502:physiology; D017557:Ventral Tegmental Area / Q000033:anatomy & histology / Q000000981:diagnostic imaging / Q000502:physiology