And when estrogen, the female hormone
was used, there was only a response in
the olfactory portion of the brains of
straight women. Homosexual men had their
primary response also in the olfactory
area, with a very small reaction in the
hypothalamus, while heterosexual men
responded strongly in the reproductive
region of the brain.
Savic said the group is also doing a
study involving homosexual women but
those results are not yet complete.
In a separate study looking at
people's response to the body odors of
others, researchers in Philadelphia
found sharp differences between gay and
straight men and women.
"Our findings support the contention
that gender preference has a biological
component that is reflected in both the
production of different body odors and
in the perception of and response to
body odors," said neuroscientist Charles
Wysocki, who led the study.
In particular, he said, finding
differences in body odors between gay
and straight individuals indicates a
physical difference.
It's hard to see how a simple choice
to be gay or lesbian would influence the
production of body odor, he said.
Wysocki's team at the Monell Chemical
Senses Center studied the response of 82
heterosexual and homosexual men and
heterosexual and homosexual women to the
odors of underarm sweat collected from
24 donors of varied gender and sexual
orientation.
They found that gay men differed from
heterosexual men and women and from
lesbian women, both in terms of which
body odors gay men preferred and how
their own body odors were regarded by
the other groups.
Gay men preferred odors from gay men,
while odors from gay men were the least
preferred by heterosexual men and women
and by lesbian women in the study. Their
findings, released Monday, are to be
published in the journal Psychological
Science in September.
The Swedish research was funded by
the Swedish Medical Research Council,
the Karolinska Institute and the Magnus
Bergvall Foundation. Wysocki's research
was supported by the Monell Center.
