Erotic images spur the brain

Researchers at Washington University School of Medicine officially tell us what we always knew.

WASHINGTON, DC: This surely is a no brainer experiment. A new study published by researchers at the Washington University School of Medicine in the US says that the brain is quickly turned on and tuned in when a person views erotic images. D-uh?

Not really, says its lead author Andrey P Anokhin, a research assistant professor of psychiatry at the medical school. The research was conducted by measuring the brain waves of 264 women as they viewed 55 colour slides with scenes from water skiers to snarling dogs to partly-naked couples in sexually aggressive poses. “The results surprised us,” says Anokhin. “We believed both pleasant and disturbing images would evoke a rapid response, but erotic scenes always elicited the strongest response.”

The study report said that when volunteers viewed erotic visuals, their brains produced electrical responses that were stronger than those elicited by other any other kind of pictures, including those that were overly pleasant or overly violent or disturbing. It added that this difference in immediate brainwave response suggests that different neural circuits may be involved in the processing of erotic images.

A press release by the medical schools says that the volunteers had “electrodes on their scalps measuring changes in the brain’s electrical activity called event-related potentials (ERPs). The researchers learned that regardless of a picture’s content, the brain acts very quickly to classify the visual image. The ERPs begin firing in the brain’s cortex long before a person is conscious of whether they are seeing a picture that is pleasant, unpleasant or neutral.

“But when the picture is erotic, ERPs begin firing within 160 milliseconds, about 20 percent faster than occurred with any of the other pictures. Soon after, the ERPs begin to diverge, with processing taking place in different brain structures for erotic pictures than those that process other images.”

The methodology was simple: Pictures appeared on a screen at 12 to 18 second intervals, and each picture remained on the screen for about 6 seconds. The subjects — all female — were instructed to look at the pictures.

Although it is commonly believed that men respond more subjectively to erotic visuals, Anokhin says the fact that the women’s brains in this study quickly responded to erotic pictures suggests that, perhaps for evolutionary reasons, our brains are programmed to preferentially respond to erotic material. “Usually men subjectively rate erotic material much higher than women,” he says. “But, women have responses as strong as those seen in men.”