clitoris and vagina are represented in the genital brain

Brain control of the clitoris and vagina, as well as of the nipple, was not known in detail until a decade ago. Komisaruk and colleagues at the Psychology Department of Rutgers University, in Newark, New Jersey, USA, established what they called the genital sensory cortex in women.

Komisaruk BR, Wise N, Frangos E, Liu W‐C, Allen K, and Brody S. Women’s clitoris, vagina and cervix mapped on the sensory cortex: fMRI evidence. J Sex Med 2011; 8:2822–2830.

In their experiment, the women applied clitoral, vaginal, and cervical self‐stimulation while the regional brain responses were identified with functional MRI. Previously, the same regions had been identified in the Penfield homunculus based on electrical stimulation of the brain in men, and male anatomy was already relatively well studied.

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Knowledge of the male neurological anatomy and function was already relatively well known.

Kell C.A et al The sensory cortical representation of the human penis: Revisiting somatotopy in the male homunculus. J Neurosci. 2005; 25: 5984-5987

Georgiadis J. and Holstege G. Human brain activation during sexual stimulation of the penis. J Comp Neurol. 2005; 493: 33-38

Bradley W.E. et al Human cerebrocortical potentials evoked by stimulation of the dorsal nerve of the penis. Somatosens Mot Res. 1998; 15: 118-127

Makela J.P. et al. Dorsal penile nerve stimulation elicits left‐hemisphere dominant activation in the second somatosensory cortex. Hum Brain Mapp. 2003; 18: 90-99

Nakagawa et al. Somatosensory evoked magnetic fields elicited by dorsal penile, posterior tibial, and median nerve stimulation. Electroencephalogr Clin Neurophysiol. 1998; 108: 57-61

Narici L. et al Neuromagnetic somatosensory homunculus: A non‐invasive approach in humans. Neurosci Lett. 1991; 2: 51-54

The Rutgers group set out towards understanding the neural systems underlying female sexual response. They confirmed the anatomical and functional female data, and reviewed the relevant literature in a series of papers.

Komisaruk B.R. et al Brain activation during vaginocervical self‐stimulation and orgasm in women with complete spinal cord injury: fMRI evidence of mediation by the Vagus nerves. Brain Res. 2004; 1024: 77-88

Komisaruk B.R. et al The science of orgasm. The Johns Hopkins University Press, 2006

Komisaruk B.R. et al Women’s clitoris, vagina and cervix mapped on the sensory cortex, using fMRI. Soc Neurosci. 2009; 562: 18

In the original investigation they mapped the sensory cortical fields of the clitoris, vagina, uterine cervix and nipple, Sensory cortical responses to clitoral, vaginal, cervical, and nipple self‐stimulation were mapped using functional magnetic resonance imaging (fMRI). For points of reference on the sensory homunculus, they mapped responses to stimulation of the thumb and great toe. Clitoral, vaginal, and cervical self‐stimulation activated regions clustered in the medial cortex of the parietal lobe, the so-called medial paracentral lobule. Nipple self‐stimulation activated the genital sensory cortex and the thoracic region of the sensory homunculus.