Published: 2008-06-23 00:00 | Updated: 2014-04-08 17:05

Brain similarities between homosexuals and opposite sex

In a study recently published in PNAS, scientists at Karolinska Institutet show that the brains of gay men and women in some aspects are similar to the brains of those of the opposite sex.

Using MRI and PET technology Associate Professor Ivanka Savic-Berglund and Senior Physician Per Lindström studied the brains of 90 persons, both heterosexual and homosexual, and found that heterosexual men and homosexual women showed a rightward cerebral asymmetry, whereas volumes of the cerebral hemispheres were symmetrical in homosexual men and heterosexual women. The scientists also found that homosexual men and women showed sex-atypical connections in the part of the brain called amygdala.


PET and MRI show differences in cerebral asymmetry and functional connectivity between homo- and heterosexual subjects.
Savic I, Lindström P
Proc. Natl. Acad. Sci. U.S.A. 2008 Jul;105(27):9403-8