Location of Brain Electrical Source Activation according to Visually Stimulated Sexual Arousal: A Cross Spectral Analysis using Low Resolution Brain Electromagnetic Tomography (LORETA)

Purpose: Low resolution brain electromagnetic tomography (LORETA) is a kind of functional imaging technique and it is also an up-to-date technique for conducting electroencephalography (EEG) analysis. We tried to investigate the locations on the cerebral cortex that are activated by visually stimulated sexual arousal. Materials and Methods: Thirty-three male volunteers (age range: 24.7±1.7 years) among all the right-handed medical students at our university were enrolled in this study. The EEGs included the segments recorded during resting, watching a music-video, intermission and watching a porno-video. The LORETA images of the cross-spectral analysis were obtained with using segments of LORETA-KEY (KEY Institute for Brain-Mind Research, Switzerland) software. Results: In the statistical nonparam etric m aps (SnPM) of each spectrum and the delta, theta and alpha waves did not show the increased current density. The beta 1, 2 and 3 activity showed the point of maximal current densities in the anterior parahippocampal gyrus of the left limbic lobe and the superior temporal gyrus of both temporal lobes, the superior temporal gyrus of the right temporal lobe, the precuneus of the right parietal lobe, the medial frontal gyrus of the left frontal lobe, the middle occipital gyrus of the right occipital lobe, the superior temporal gyrus of both temporal lobes and the superior frontal gyrus of the right frontal lobe. Conclusions: The sexual arousal by visual stimulation may activate the anterior parahippocampal gyrus of the left limbic lobe, the superior temporal gyrus of both temporal lobes, the precuneus of the right parietal lobe, the medial frontal gyrus of the left frontal gyrus, and the middle occipital gyrus of the right occipital lobe. (Korean J Urol 2006;47:779-785)