Can a person’s promiscuous tendencies be determined by their neurological response to pornographic images? A study conducted at the University of California, Los Angeles, has revealed that a person’s brain activity after viewing a sexual image could determine how many sexual partners they have been involved with.

"These are the first data we know of that link brain responses to actual sexual risk behaviors," research scientist in the department of psychiatry in the UCLA Semel Institute for Neuroscience and Human Behavior, Nicole Prause, said in a statement. "If your brain responds very strongly even to very tame pictures of sex, then you seem to be easily sexually excited in the real world, too. If we show very explicit sex pictures, eventually everyone's brain responds strongly. It is those weaker images, just hinting at sex, that show the difference."

Prause and her colleagues recruited 40 male and 22 female study participants between the ages of 18 and 40. Each respondent was asked to fill out a survey that included the question, “How many partners have you had sexual intercourse with in the last 12 months?" Following the questionnaire, they were shown 225 images that were either non-sexual, pleasant (such as a picture of someone skydiving), neutral (such as a portrait), and sexual (ranging from G-rated to explicit).

The research team used electroencephalogram (EEG) to measure the brain’s electrical activity when viewing an image that had nothing to do with sex, an image with some romance, or a pornographic image. Positive potential brain activity determined the emotional intensity of each participant’s response to the image. Individuals who reported a high number of sexual partners in the questionnaire part of the study also exhibited the same positive potential response to the variety of sexual images.

"This pattern helps tell us why people may choose to pursue new sex partners," Prause added. "For example, some researchers have suggested that people may pursue new partners to experience sexual excitement that they did not experience in their regular lives or with their regular partner. These results, she said, "suggest that new partners actually might be pursued because people have high sexual excitement in response to any potential partner, whether regular or new. This distinction is very important if we want to help people feel in control of their sexual urges."

Source: Steele V, Staley C, Sabatinelli D, Prause N. Late positive potential to explicit sexual images associated with the number of sexual intercourse partners. Social Cognitive and Affective Neuroscience. 2014.