title: Neural substrates of sexual arousal in heterosexual males: event-related fMRI investigation.
abstract: BACKGROUND
  Sexual behavior is an important role for the survival of species. The advancement of brain imaging methods has enabled the understanding of the brain mechanism related to sexual arousal. The previous studies on the brain mechanism related to sexual arousal have mostly conducted on block design paradigm.
  
  
  METHODS
  Despite its requirement for stricter experimental control, the event-related paradigm is known to be more efficient in detecting instant emotional and cognitive responses. The paradigm also enables the observation of hemodynamic responses through time. Therefore, this study used the event-related fMRI to examine the brain activation in various areas associated with sexual arousal as well as changes in hemodynamic responses with time.
  
  
  RESULTS
  Strong activations were observed in the various areas associated with sexual arousal comprised of various factors: (1) activation areas related to cognitive factors: the occipital lobe and parietal lobe; (2) activation areas related to emotional factors: the thalamus and amygdala; (3) activation areas related to motivational factors: the anterior cingulate gyrus, orbitofrontal cortex, and insula; and (4) activation areas related to physiological factors: the precentral gyrus, putamen, and globus pallidus. We also identified the activation of the putamen and globus pallidus that were not well observed in previous block design studies. In the result of the hemodynamic response, the neural activity in those areas showed more transient aspects of the hemodynamic responses relative to the neural activity of other areas.
  
  
  CONCLUSIONS
  These results suggested that the event-related paradigm is better at detecting the neural activity of the brain regions, which tend to appear suddenly, but disappear soon.
authors.affiliation: Department of Psychology, Brain Research Institute, Chungnam National University, Koong-dong 220, Yusung-gu, Daejeon, Korea. suk6124@naver.com.|Bioimaging Research Team, Division of Bioconvergence Analysis, Korea Basic Science Institute, eongudanji-ro 162, Ochang, Cheongju, Korea. suk6124@naver.com.
authors.forename: Ji-Woo
authors.initials: JW
authors.lastname: Seok
authors.affiliation: Department of Psychology, Brain Research Institute, Chungnam National University, Koong-dong 220, Yusung-gu, Daejeon, Korea. jhsohn@cnu.ac.kr.
authors.forename: Jin-Hun
authors.initials: JH
authors.lastname: Sohn
authors.affiliation: Bioimaging Research Team, Division of Bioconvergence Analysis, Korea Basic Science Institute, eongudanji-ro 162, Ochang, Cheongju, Korea. cheong@kbsi.re.kr.
authors.forename: Chaejoon
authors.initials: C
authors.lastname: Cheong
mesh_terms: D000328:Adult; D001143:Arousal; D001921:Brain / Q000502:physiology*; D001931:Brain Mapping; D020010:Heterosexuality / Q000502:physiology*; D006801:Humans; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D012725:Sexual Behavior / Q000502:physiology*; D055815:Young Adult