title: Sexual motivation is reflected by stimulus-dependent motor cortex excitability.
abstract: Sexual behavior involves motivational processes. Findings from both animal models and neuroimaging in humans suggest that the recruitment of neural motor networks is an integral part of the sexual response. However, no study so far has directly linked sexual motivation to physiologically measurable changes in cerebral motor systems in humans. Using transcranial magnetic stimulation in hetero- and homosexual men, we here show that sexual motivation modulates cortical excitability. More specifically, our results demonstrate that visual sexual stimuli corresponding with one's sexual orientation, compared with non-corresponding visual sexual stimuli, increase the excitability of the motor cortex. The reflection of sexual motivation in motor cortex excitability provides evidence for motor preparation processes in sexual behavior in humans. Moreover, such interrelationship links theoretical models and previous neuroimaging findings of sexual behavior.
authors.affiliation: Department of Psychiatry and Psychotherapy.
authors.forename: Martin
authors.initials: M
authors.lastname: Schecklmann
authors.affiliation: Department of Psychiatry and Psychotherapy.
authors.forename: Kristina
authors.initials: K
authors.lastname: Engelhardt
authors.affiliation: Institute of Experimental Psychology, University of Regensburg, Regensburg, Germany.
authors.forename: Julian
authors.initials: J
authors.lastname: Konzok
authors.affiliation: Department of Psychiatry and Psychotherapy, Max Planck Institute of Psychiatry, Munich, Germany, and.
authors.forename: Rainer
authors.initials: R
authors.lastname: Rupprecht
authors.affiliation: Institute of Experimental Psychology, University of Regensburg, Regensburg, Germany.
authors.forename: Mark W
authors.initials: MW
authors.lastname: Greenlee
authors.affiliation: Department for Forensic Psychiatry, University Hospital of Psychiatry, Zurich, Switzerland.
authors.forename: Andreas
authors.initials: A
authors.lastname: Mokros
authors.affiliation: Department of Psychiatry and Psychotherapy.
authors.forename: Berthold
authors.initials: B
authors.lastname: Langguth
authors.affiliation: Department of Psychiatry and Psychotherapy, timm.poeppl@klinik.uni-regensburg.de.
authors.forename: Timm B
authors.initials: TB
authors.lastname: Poeppl
mesh_terms: D000328:Adult; D001143:Arousal / Q000502:physiology; D019054:Evoked Potentials, Motor; D020010:Heterosexuality / Q000502:physiology / Q000523:psychology; D006716:Homosexuality / Q000502:physiology / Q000523:psychology; D006801:Humans; D008297:Male; D009042:Motivation / Q000502:physiology*; D009044:Motor Cortex / Q000502:physiology*; D009415:Nerve Net / Q000502:physiology; D010775:Photic Stimulation; D012725:Sexual Behavior / Q000502:physiology* / Q000523:psychology*; D050781:Transcranial Magnetic Stimulation; D055815:Young Adult
keywords: cortical excitability; motor evoked potentials; sexual motivation; transcranial magnetic stimulation