Research coming from the University of Zurich has shown that a person’s sex as well as sexual orientation is linked to the way that person “reads” other’s faces:
Social communication requires the accurate analysis of the intentions of other individuals. To this end, men and women likely adopt strategies of “face reading” in order to successfully interact with potential sexual partners. Thus, it is reasonable to assume differential patterns of activation in the hetero- and homosexual brains in response to faces of the same or opposite sex…
To test this hypothesis, the researchers used functional Magnetic Resonance Imaging (fMRI), a non-invasive technique that permits the localization of regions in the human brain activated during cognition and experience. The researchers scanned 40 subjects (10 heterosexual women, 10 heterosexual men, 10 homosexual women, 10 homosexual men, mean age 26 plus/minus 3 years) that were classified as hetero- or homosexuals on the basis of their self-report. While in the MR scanner, the subjects either passively viewed faces or pressed one of three buttons to indicate whether a face was Attractive, Neutral, or Unattractive, and reaction times were recorded.
The researchers found that, consistent with their hypothesis, the gender of a viewed individual, when the sexual preference of the viewer was taken into account, did make a difference in the reactions seen in the thalamus and the orbitofrontal cortex, a region of the brain’s reward circuitry. Heterosexual women and homosexual men exhibited a significantly greater response to male faces, whereas heterosexual men and homosexual women responded significantly more to female faces.