WEDNESDAY, Sept. 12, 2012 (HealthDay News) -- As a species, humans are disgusted by many things. But somehow, they keep reproducing even though sex can be a bit, well, icky.
Why?
A small new study suggests sexual arousal makes people more willing to accept things that might otherwise disgust them.
The research is limited: It only looked at women and their willingness to deal with normally disgusting things when they were (or weren't) sexually aroused. But there's more to the findings than "pop psychology," said study author Charmaine Borg, a graduate student at the University of Groningen in the Netherlands.
When sexual arousal is low, which can occur due to a disorder, women might become more disgusted by sex and want to avoid it, she said. This can result in "a downward spiral," she suggested, in which "lack of sexual arousal may interfere with functional sex as it may prevent the reduction of disgust."
Sex can seem inherently gross, Borg said, because it involves things such as saliva, semen and sweat, which people typically stay away from to avoid contamination.
But still, people -- or at least most people -- want to have sex. Borg quoted Sigmund Freud as saying: "A man, who will kiss a pretty girl's mouth passionately, may perhaps be disgusted by the idea of using her toothbrush."
In the new study, which appears in the September issue of the journal PLoS One, researchers assigned 90 women to one of three groups. The researchers tried to arouse one group by showing them "female-friendly" erotica, while another group watched a clip of high-energy outdoor activities such as rafting and sky diving. The third group watched a video of a train ride in the hope that they wouldn't be stimulated at all.
Then the researchers asked the women to accomplish several tasks, some of which would normally be seen as gross, such as drinking from a cup with a real-seeming bug in it (the insect was actually fake), wiping their hands with what appeared to be a used tissue, eating a cookie that was next to a worm or putting their finger in a tray of used condoms.
"The group of women that were sexually aroused were more willing than the other groups to do the tasks requested and did significantly more tasks than the other groups," Borg said. "Sexual arousal seems to be playing an active role in here, making us do things that we would not necessarily consider otherwise."
Does the same go for men? Other research suggests that it does, Borg said.
So what's going on? Is it purely a case of sexual arousal distracting women? Borg doesn't think so, because the women who watched the high-energy outdoor videos -- which stimulated them in a nonsexual way -- still weren't as willing to tackle the gross tasks as the sexually aroused women.
Clark McCauley, a professor of sciences and mathematics at Bryn Mawr College who has studied disgust, said sexual arousal didn't seem to make a huge difference in creating more tolerance for disgusting things. "It seems likely that the big effect in reducing disgust is for disgust stimuli relating to a physically present and willing partner," he said. "In which case, this study is only preliminary for understanding how sexual arousal reduces disgust."
Unfortunately, McCauley said, the researchers "didn't ask their subjects about their sexual experience and whether they ever felt disgusted before, during or after sex. Or disgusted when thinking about sex at a time when they are not aroused."
More information
For details on sexual health, visit the U.S. National Library of Medicine.
