WEDNESDAY, May 17 (HealthDay News) -- A brain imaging study suggests that women who are lesbians respond to putative human pheromones with some similarity to heterosexual men rather than to heterosexual women, according to a report published online May 16 in the Proceedings of the National Academy of Sciences Early Edition.
Using positron emission tomography (PET), Ivanka Savic, M.D., Ph.D., and colleagues from the Karolinska Institute in Stockholm, Sweden, previously found pheromone responses in homosexual men closely mirrored responses in heterosexual women. In the current study, the group used PET analysis to determine the response to two putative pheromones, AND and EST, in 12 lesbian women.
The investigators found that the EST response in lesbians was governed by the anterior hypothalamus as it was in heterosexual men. However, lesbians also responded to AND like heterosexual women, but using the olfactory network rather than the hypothalamus. The differences were still apparent even when limiting the analysis to women with higher expression of homotypical pattern, measured by a scale developed by Alfred Kinsey and colleagues.
The authors suggest the weaker relationship between lesbians and heterosexual men compared with homosexual men and heterosexual women might be because lesbians are more "sex-flexible," as cited in previous studies. "The data support the notion of a coupling between hypothalamic neuronal circuits and sexual preferences and encourage further evaluation of the possible neurobiology of homosexuality and human sexuality in general," they conclude.
Abstract
Full Text (subscription or payment may be required)
