What turns you on? Our sexual affinities live on a spectrum, both narrow and wide. We enjoy what we enjoy – and maybe more? In today’s sex science news, where I tell you about a new sex study that just got published, we’re going to talk about research that measured sexual arousal in men and women by taking the temperature of their genitals when watching porn.
In previous studies, when men who identify as straight were shown porn, their genitals (penises) got aroused only to sexual images of women and not to images of men — what we call “gender specific or categorical reactions”. When women who identify as straight were shown porn, their genitals (vaginas) were equally aroused to both images of men and women. So, straight women’s vaginas acted bisexually, whereas straight men’s penises did not.
A major source of criticism with this line of research has been that we’re measuring arousal in men and women with different techniques and equipment. Men’s arousal has typically been measured men with what is called a penile plethysmograph (PPG), a string that men put around their penis that measures the size of their erection – pretty straightforward. For women, on the other hand, we’ve used a device called a vaginal photoplethysmograph (VPP), a tampon-sized photosensitive camera goes inside the vagina and measures blood flow through the genitals through light — the redder it gets, the more blood flow.
While both devices rely on the well-established fact that genitals engorge with blood when people get aroused; they measure this engorgement very differently. So it was possible that this gender-specificity in men’s arousal, but the gender non-specificity in women’s arousal was due to the different methodology.
This is where this new study comes in. Published last week in the Journal of Psychophysiology, this study used the exact same methodology to measure genital arousal men and women while watching porn: the thermographic camera.
How? Once left alone in the lab, male and female study participants strip from the waste down, spread eagle on a comfy chair in front of a thermographic cameras, and start watching gender specific porn (either men or women masturbating (this is done so that a stimulus of only one gender is present per clip). The cameras measure how much heat was generated in the genital area while they watched the erotic films: the more heat, the more arousal.
What they found with this thermo-imaging is the same thing that prior studies have found with the PPG and the VPG: Straight men’s genitals got heated only when watching women (but not men) masturbating, whereas straight women’s genitals got heated up watching both men or women. This suggests that the gender-categorical responding of straight men’s penises, but the gender-nonspecific responding of straight women’s genitals is real, not an artifact of different methodologies.
Of course, this is what the vaginas (and penises) are saying. Genital arousal is not the same as psychological arousal and desire. In fact, there are reasons to believe that, especially for women, genital arousal may not be the best predictor of psychological arousal, desire, or sexual orientation. So please don’t take these results to mean that all straight women are actually bisexual, or that they want to have a threesome with you and another woman. The best way to detect a woman’s “true” sexual orientation is to ask her about it.