Where Does the Female Orgasm Live in the Brain?

Where in the brain does the female orgasm live? You might assume that the answer to this question is already known. It’s not. For many years, the precise location of the human female genital representation has been controversial. A better understanding of the location will allow scientists to determine whether repeated sexual behavior induces changes in its structure or connectivity.

Initial studies in the 1950s placed the genital sensory cortex below the foot area. Later studies placed it adjacent to the hip and knee cortical areas. Both conclusions proved to be incorrect. The mode of stimulation that was used in earlier studies contributed to the heterogeneous results concerning the location of the genital field in female humans. One problem was that the electrical stimulation utilized in these early studies is not equivalent to manual sensory stimulation. Furthermore, self-delivered or partner-delivered stimulation involved touching of areas adjacent to the genitals that may have confounded the neurological representation.

A recent study published in the Journal of Neuroscience mapped the female genital field in 20 adult women using fMRI in response to sensory stimulation of the clitoris, as compared to sensory stimulation of a control region, in this case, the right hand. In addition, this study examined the capacity for structural change following repeated activation of this brain region by physiologically relevant clitoral stimulation. Given that the human brain has a substantial capacity for plasticity as a function of experience, this study also investigated whether the human genital sensory cortical area field is capable of structurally adapting as a function of sexual behavior.

The current study mapped the most activated individual genital cortical sensory areas per hemisphere for each woman and measured changes in thickness. The study discovered that the thickness of the individually mapped genital cortical sensory areas varies with the frequency of sexual intercourse in the previous 12 months. Specifically, the area of interest was identified in the dorsolateral postcentral gyrus in the anterior parietal Brodman areas BA3a, BA3b, BA1, and BA2. (If you would like to learn more about the functions of this region, please see the references below.) Most importantly, the individual location of peak neural activations in response to clitoral stimulation varied considerably between women, however, the region of interest did not change.

Unexpectedly, the thickness of the left, but not the right, genital sensory cortical areas, of the individually mapped brain regions from each woman, varied with the frequency of sexual intercourse. The discovery that the changes only occurred in the left hemisphere is surprising given that the neural representation of the clitoris is bilateral. However, left-hemisphere dominance of neural plasticity has been previously reported for structural changes associated with learning and motor skill training.

In summary, these data are consistent with the hypothesis that the female genital cortical sensory field in the left hemisphere of the brain has capacity for structural plasticity depending on its use, commensurate with the general “use-it-or-lose-it” principle of experience-dependent plasticity. The functional consequences of these changes in structure remain to be determined.