A new study has found that pornography triggers brain activity in people with compulsive sexual behavior — sometimes known as sex addiction — similar to that triggered by drugs in the brains of drug addicts.
Researchers at the University of Cambridge note that as many as one in 25 adults is affected by compulsive sexual behavior, described as an obsession with sexual thoughts, feelings, or behavior they are unable to control. This can have a significant impact on their lives, leading to distress and feelings of shame, they note.
For the study, researchers examined the brain activity of 19 men affected by compulsive sexual behavior and compared them to the same number of healthy volunteers. The researchers report that the 19 men started watching pornography at earlier ages and in higher proportions when compared to the healthy volunteers.
“The patients in our trial were all people who had substantial difficulties controlling their sexual behavior and this was having significant consequences for them, affecting their lives and relationships,” said Dr. Valerie Voon, a Wellcome Trust Intermediate Clinical Fellow at the University of Cambridge.
“In many ways, they show similarities in their behavior to patients with drug addictions. We wanted to see if these similarities were reflected in brain activity, too.”
The men were shown a series of short videos featuring either sexually explicit content or sports. Their brain activity was monitored using functional magnetic resonance imaging (fMRI), which uses a blood oxygen level dependent (BOLD) signal to measure brain activity.
The researchers found that three regions were more active in the brains of the men with compulsive sexual behavior — the ventral striatum, dorsal anterior cingulate, and amygdala. These regions also are activated in drug addicts when shown drug stimuli, the researchers reported.
The ventral striatum is involved in processing reward and motivation, while the dorsal anterior cingulate is involved in anticipating rewards and drug cravings. The amygdala is involved in processing the significance of events and emotions, the researchers explained.
The researchers also asked the men to rate the level of sexual desire they felt while watching the videos, and how much they liked the videos.
As anticipated, the men with compulsive sexual behavior showed higher levels of desire during the sexually explicit videos. This desire was correlated with higher interactions between the dorsal cingulate, ventral striatum, and amygdala.
But the researchers note that the men reported they did not necessarily like the videos.
The researchers also found a correlation between brain activity and age. The younger the man, the greater the level of activity in the ventral striatum in response to pornography, they found. This association was strongest in the men with compulsive sexual behavior, they add.
The frontal control regions of the brain — essentially, the “brakes” on compulsivity — continue to develop into the mid-20s and this imbalance may account for greater impulsivity and risk-taking behaviors in younger people, the researchers hypothesize.
The findings related to age suggest that the ventral striatum may be important in the developmental of compulsive sexual behaviors, as it is in drug addiction, although direct testing of this possibility is needed, the researchers noted.
“There are clear differences in brain activity between patients who have compulsive sexual behavior and healthy volunteers. These differences mirror those of drug addicts,” Voon said.
“Whilst these findings are interesting, it’s important to note, however, that they could not be used to diagnose the condition. Nor does our research necessarily provide evidence that these individuals are addicted to porn — or that porn is inherently addictive. Much more research is required to understand this relationship between compulsive sexual behavior and drug addiction.”
The study was published in the journal PLOS ONE.
Source: University of Cambridge