Women sniff out sexy men

Last updated: Tuesday, January 13, 2009 Print

Sex is all in the sweat.

All socio-emotional meanings, including sexual ones, are conveyed in human sweat, according to a study published in the Journal of Neuroscience.

Scientists have long known that animals use scent to communicate. So Denise Chen, assistant professor of psychology at Rice University in the US, looked at how the brains of female volunteers processed and encoded the smell of sexual sweat from men. The results indicated that we operate the same way as animals do.

The experiment directly studied natural human sexual sweat using functional magnetic resonance imageing (fMRI). Nineteen healthy female subjects inhaled olfactory stimuli from four sources, one of which was sweat gathered from sexually aroused males.

The research showed that several parts of the brain are involved in processing the emotional value of the olfactory information. These include the right fusiform region, the right orbitofrontal cortex and the right hypothalamus.

"With the exception of the hypothalamus, neither the orbitofrontal cortex nor the fusiform region is considered to be associated with sexual motivation and behaviour," Chen said. "Our results imply that the chemosensory information from natural human sexual sweat is encoded more holistically in the brain rather than specifically for its sexual quality."

"Humans are evolved to respond to salient socio-emotional information", the authors wrote. "Distinctive neural mechanisms underlie the processing of emotions in facial and vocal expressions. The findings help explain the neural mechanism for human social chemosignals."

The research appeared in the December 31 issue of the Journal of Neuroscience and was supported in part by the US National Institutes of Health.

(EurekAlert, January 2009)