Hypothalamus, sexual arousal and psychosexual identity in human males: a functional magnetic resonance imaging study

In chapter 12, we discussed the importance of the hypothalamus. It is involved in many involuntary functions, such as temperature control, biological rhythms, and sexual drive. In this article, researchers look at how the hypothalamus is involved with sexual response in males. The researchers wanted to investigate the correlation between cerebral responses during sexual arousal and the DSI, or deep sexual identity, in males. The DSI of the participants is assessed using a test known as the Franck drawing completion test (FDCT). The test provides accordance/non-accordance between self-reported and psychological sexual identity of the participant. They used a sample of 18 healthy, self-professed heterosexual males. The participants were shown 6 erotic videos, 6 sports video, and 12 neutral videos. Neutral videos were shown in between and only used as a relaxing pause between the 2 main stimuli. Cerebral activity of the participants was monitored by functional magnetic resonance imaging. Sexual arousal was found during all erotic videos and none of the control videos. There was a statistically significant positive correlation between the blood oxygen level-dependent signal in the bilateral hypothalamus and the FDCT during the erotic stimuli. An increase in blood oxygen level-dependent activation positively correlated with a higher DSI profile. These results imply that the psychosexual identity of males is related to the functional features of the bilateral hypothalamus. Also, this correlation was found only in the bilateral hypothalamus, which suggests that the psychosexual identity of males is related strictly to this region of the brain. This part of the hypothalamus is thought to be involved with instinctual drives such as reproduction.

Brunetti, M. M., Babiloni, C. C., Ferretti, A. A., Del Gratta, C. C., Merla, A. A., Olivetti Belardinelli, M. M., & Romani, G. L. (2008). Hypothalamus, sexual arousal and psychosexual identity in human males: a functional magnetic resonance imaging study. European Journal of Neuroscience, 27(11), 2922-2927. Retrieved from EBSCOhost. doi:10.1111/j.1460-9568.2008.06241.x