Denise Chen of Rice University looked at how the brains of female volunteers processed and encoded the smell of sexual sweat from men. Scientists have long known that animals use scent to communicate, but Chen's findings represent an effort to expand knowledge of how humans' sense of smell complement their more powerful senses of sight and hearing.

The researchers studied natural human sexual sweat using functional magnetic resonance imaging. Nineteen healthy female subjects inhaled olfactory stimuli from four sources, one of which was sweat gathered from sexually aroused males.

The study, published in the Journal of Neuroscience, showed that several parts of the brain are involved in processing the emotional value of the olfactory information -- the right fusiform region, the right orbitofrontal cortex and the right hypothalamus.

"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," Chen said in a statement.