PhD ceremony Mr. H.K. Huynh: Imaging neurophysiology of human sexuality using positron emission tomography

PhD ceremony: Mr. H.K. Huynh

Dissertation: Imaging neurophysiology of human sexuality using positron emission tomography

Promotor(s): prof. R.A.J.O. Dierckx

Faculty: Medical Sciences

Neurophysiology is a branch of physiology and neuroscience that focuses on the functioning of the different parts of the nervous system. The aim of this thesis is to improve our understanding of the neurophysiology of human sexuality by using functional neuroimaging, in particular Positron Emission Tomography (PET). First a short introduction is given to neurophysiology of sexuality as well as PET imaging and the data analysis methods employed in this thesis. Subsequently a more detailed description of the human brain activations during sexual stimulation, ejaculation and orgasm is given and linked to brain circuits involved in the mating behavior of cats. An interesting and important finding is the deactivation of the visual cortex in women during high erotic movies, but not low erotic and neutral movies. Also, we demonstrated for the first time that neuroimaging techniques could identify increases in pituitary activation in 11 healthy women during real orgasm but not in 11 healthy men during ejaculation. The dorsolateral pontine tegmentum and the ventrolateral pons that we found to be activated in ejaculation and orgasm are also involved in micturition. We propose to name these regions respectively the pelvic organ stimulating center (POSC) and the pelvic floor stimulating center (PFSC) which both act as the final brain output for muscle activity involved in micturition, ejaculation and orgasm.