Recently Brain Blogger featured an article entitled Your Brain on Sex and Love. While it delineated a few recent studies that focused on what goes on in the brain during sex, few recognize how little is known about human sexuality, particularly the neural and psychological responses that stem from it. Logistically, it is difficult to study human sex in a lab setting, simply because it is difficult for test subjects to engage in intercourse, or even to self-stimulate, in an fMRI scanner. MindHacks explains how the alternative use of PET scanners is still problematic:

[The test subjects] still had some considerable problems to overcome though, not least of which was timing an orgasm to occur during a predefined time-slot, during which brain activity could be monitored. PET requires a radioactive tracer to be injected into the bloodstream, and although the radiation is very weak, it’s best to use only as much as necessary. This means the intuitive approach of continuous scanning and waiting for the pop of the cork is just not feasible.

Female sexuality is particularly enigmatic, simply because the sex function in women is so much more complex than that of their male counterparts. A study conducted by Dutch scientist Gert Holstege and featured in a BigThink article showed that while the areas in male brains activated during orgasm were not surprising, the activated areas in the female brains were slightly different. For one, the female brain becomes noticeably silent in certain areas, like in the lateral orbitofrontal cortex and the dorsomedial prefrontal cortex, two areas in the brain that process feelings and thoughts associated with self-control and social judgement. Holstege noted that “at the moment of orgasm, women do not have any emotional feelings.”

New Scientist published a piece late last year featuring an experiment that revealed that pain processing centers in the brain also activate during female orgasm. Dr. Kamisaruk of Rutgers University, who is an early pioneer of neuroscieintific sex studies of the female orgasm, noted that at the moment of climax, women’s pain threshold drops drastically, and that “the fact that these areas are both active during pain and intense pleasure suggests that they may be involved in the analgesic effects of orgasm.”

While of course the study of men’s sexual response is important, it may be more important from a medical standpoint to delve into the female brain considering the much higher numbers of sexual dysfunction in women. Even women in good health have a difficult time achieving climax. Reportedly, 10% of women have never had an orgasm, and as many as 50% of women have trouble being aroused.

One interesting ability that Kamisaruk found is unique to women is that some women he worked with were able to “think themselves” to orgasm. Without using any external stimulation, women closed their eyes and, using only sometimes erotic imagery but just as commonly very random and abstract thought processes, achieved an orgasm that was indistinguishable from orgasms achieved through self-stimulation. Kamisaruk also observed that when some women visualize a certain part of the body, that part of the body becomes sensitive. Kamisaruk believes that further study on this phenomenon could be helpful beyond simply treating sexual dysfunction, but could aid in pain management and the prevention of obesity, among other common health concerns.

In the final analysis, however, as pointed out in Brain Blogger and the New York Times, sexual dysfunction can be understood on a cultural level as well. Stifled sexual pleasure, particularly in women, can result from cultural taboos and poor relationships. As such, the relatively recent excitement about so-called “women’s Viagra” is still as yet a pipe dream, and would it behoove both the scientist and the average person to understand human sexuality through as many lenses as possible.

References

Komisaruk BR, & Whipple B (2005). Functional MRI of the brain during orgasm in women. Annual review of sex research, 16, 62-86 PMID: 16913288