This is the ultra sex nerd post you’ve all been waiting for. Replace your monocles with your dork glasses for a minute and join me in geeking out on two incredible recently published – and non-trivial – items.
The first one comes from The Journal of Sexual Medecine, in Women’s Clitoris, Vagina, and Cervix Mapped on the Sensory Cortex: fMRI Evidence. Hot! The male erotic sensory bits were mapped in the 1950s – we had to wait until 2011 to have proof that our pleasure is not all in our heads, as it were. Anyway, it’s about damn time.
The female sexual brain has been charted. For the first time, the brain regions that respond to stimulation of the clitoris, cervix, vagina and nipples have been mapped in a new study.
Not surprisingly, the brain region associated with sensation from the clitoris was distinct from those that respond to stimulation of the cervix or vagina. Each area of the genitals showed up in its own spot, clustered in one region of the brain — the same region associated with genital stimulation in men — overlapping but separate.
What the researchers did not anticipate was that sensation from the nipples also excited the brain within the same region, right alongside the areas corresponding to genital stimulation, according to lead author Barry Komisaruk, a professor of psychology at Rutgers University. “That was completely unexpected,” he says. It would help explain why the nipples are erogenous zones in women, he says.
Okay, maybe *he* didn’t expect it… For the study, New Scientist’s writer Kayt Sukel bravely put herself forth as a subject, and she writes about stimulating herself as a participant for the brain mapping study in her first-person account, Sex on the brain: Orgasms unlock altered consciousness. Snip:
Komisaruk instructs me to tap my thumb with my finger for 3 minutes, then to simply imagine my finger tapping my thumb for the next 3 minutes as fMRI tracks where blood is flowing in my brain. Immediately after, I follow the same cycle with Kegel exercises – brief squeezes of the pelvic floor muscles – and then clitoral touches. I’m then asked to self-stimulate to orgasm, raising my free hand to indicate climax. Despite the unique situation, I am able to do so without too much trouble.
Next, in an excellent serving of Danish epidemiology we find Male circumcision and sexual function in men and women: a survey-based, cross-sectional study in Denmark (published June 14, 2011; 5,552 participants total, thanks Laust). Regular readers know that male circumcision has become one of my pet obsessions over the past few years. One-third of the world’s men are circumcised – cut cock is not in the majority. I’ve seen a pretty astonishing amount of misinformation about uncut cock being pushed by people with hidden and not-hidden agendas, while the health benefits and pleasure positives are either being ignored or suppressed. It’s weird. So I’m trying to find as many facts as possible to be able to deliver unbiased and accurate information about it.
The study’s abstract is a fine summary of the findings – though I do have a copy of the full text .PDF. They found that there are increased rates of orgasm difficulties in circumcised men and of a variety of sexual troubles among their female sex partners. (Circumcised men had around three times greater odds of frequent orgasm difficulties than uncircumcised men.) There is a significant portion of the paper devoted to circumcision and HIV, notably in its application toward preventing transmission in sub-Saharan Africa.
The study is absolutely fascinating. In the intro, the researchers confront the widespread beliefs surrounding the benefits of circumcision.
Yet, prevention of the rare cases of pathological phimosis remains a leading argument for proponents of routine circumcision. Other claimed benefits of circumcision, such as reduced risks of balanoposthitis, sexually transmitted infections and penile cancer, can be achieved without tissue loss through the maintenance of good penile hygiene combined with proper use of condoms, and whether circumcision reduces the risk of urinary tract infections in infancy has been questioned.
Despite the fact that no professional medical organization recommends routine circumcision, not even in the USA where most newborn boys undergo the operation, it remains a widespread belief that circumcision provides superior penile hygiene and protects against urinary tract infections, phimosis, paraphimosis, balanoposthitis, venereal diseases and cancer. Considering the organ involved with its sensitive anatomical structures, surprisingly few population based studies have been carried out to evaluate circumcision’s possible sexual consequences. A number of methodologically questionable reports have led to claims of impaired, improved or unaltered sexual function in circumcised men and their female partners.
- Women with circumcised partners more often than women with uncircumcised partners reported that their sexual needs were incompletely fulfilled; women with circumcised men also reported more difficulties such as orgasm difficulty, lubrication difficulty, irritation, infections, and painful sex (dyspareunia).
- Circumcised men were more likely than uncircumcised men to report frequent orgasm difficulties.
- The two most common sexual difficulties, premature ejaculation (reported as an occasional or frequent difficulty by 61%) and erectile difficulties (reported by 40%), were equally frequent in the two groups.
- The only behavioural difference was that circumcised men were more likely than uncircumcised men to report a lifetime history of 10 or more sex partners.
- Considering all sexual function difficulties together revealed no difference, but circumcised men were three times more likely than uncircumcised men to experience frequent orgasm difficulties which, according to an international expert panel, are either psychogenic or due to reduced penile sensitivity.
- Robustness analyses showed that these difficulties of circumcised men were not explained by an excess of anxiety or depression in this group. This suggests that reduced penile sensitivity may, at least in part, explain the difference, a situation that has been recognized for centuries and supported by recent neurophysiological studies.
Main post image via Beautiful Agony.