In recent years, a loss of sexual desire in women called HSDD (hypoactive sexual desire disorder) is generally accepted among scientists, although it remains controversial.
Sex therapists and the medical community agree that a more rigorous definition and diagnosis of HSDD is required. The reality is that most women lose interest in a sexual event at some time in their lives, for any number of good reasons. Many medical professionals are asking that HSDD be defined as a problem of longer duration, than currently required to be considered a psychiatric illness.
A new study of 26 women, carried out at Wayne State University in Detroit and presented to the American Society for Reproductive Medicine conference by lead author Dr Michael Diamond, suggests that the loss of libido is not imagined, but quantifiable in brain scans.
Scanning 19 women diagnosed with HSDD and seven without, Dr Diamond noted measureable brain activity in in response to emotional, erotic media among the seven women without HSDD. Increased activity in the insular cortices - parts of the brain believed to be involved in the processing of emotion - could not be seen on brain scans of the women diagnosed with HSDD.
The functional magnetic resonance imaging scanner measures levels of activation in different parts of the brain by detecting increased blood flow.
Dr Diamond said: “Us being able to identify physiological changes, to me provides significant evidence that it is a true disorder as opposed to a societal construct.” via BBC News
Even if true, the findings don’t confirm a cause. If a woman has lost interest in sex, it may be expected that her brain doesn’t ‘light up’ in response to erotic imagery. It must be confirmed that the HSDD women aren’t suffering from depression, which has a known effect of decreased blood flow in the brain.
A host of physiological symptoms associated with health problems and obesity also impact blood flow in the body and brain. The scan confirmation of HSDD does little to help the medical community understand the reasons behind the libido loss. ‘Altered blood flow’ is a likely result of other conditions, rather than a primary cause of HSDD.
Prior studies about female arousal among women not being treated for HSDD have shown brain activity and physiological responses when watching erotic imagery, even when the women insisted they weren’t aroused. These studies suggest a societal response where the woman isn’t comfortable — for whatever reason — admitting her sexual response, even though her body says otherwise.
In the case of Dr Diamond’s study, mind and body were on the same wave length, sending an indentical message. The woman says she feels a loss of libido and her brain scan backs up that assertion, compared to neurological activity in the brains of women not suffering from HSDD.