“It felt like desire, but it was more like compulsion.”
This is how one compulsive pornography user described the experience. This man stated that he spent eight to ten hours a day watching pornography. “Afterwards, I’d feel guilty for wasting the whole day watching, and shame because I couldn’t stop myself,” he explained.
This man’s intense difficulty controlling his impulse to watch pornography are experienced by countless others around the globe. One team of Korean researchers decided to investigate what this kind of out-of-control sexual behavior looks like in the brain.
The researchers built on previous studies, which found that individuals with “problematic hypersexual behavior” (people with sex/porn addiction) experience greater craving for pornography and show differences in the “critical thinking” part of the brain, the prefrontal cortex. Their own study aimed to investigate further the structural and functional brain changes that may make controlling behavior more difficult.
Researchers scanned the brains of 17 young men aged 20-33 with PHB, that is, problematic hypersexual behavior (behavior including pornography use), and compared them with the brains of 17 age-matched healthy controls.
Pornography Research
The study used two MRI techniques to measure brain differences. First, the scientists measured differences in brain structure between the groups, using an MRI technique called Voxel Based Morphometry. Second, they measured differences in temporal lobe functioning using resting-state fMRI. Temporal lobe functioning is important for reward-based learning. It’s therefore associated with addiction.
The researchers reported several important findings:
- The subjects with PHB viewed pornography and engaged in sexual behavior more frequently than the control group. They also scored higher on two sexual-addiction tests. This is important because it refutes a popular myth about pornography addicts, namely that they don’t “watch more pornography; they just feel worse about watching it.” Also, PHB subjects reported becoming sexually active at a younger age than controls, suggesting that early exposure to porn and early sexual activity may be risk factors for developing problematic sexual behavior later on.
- PHB subjects had less gray matter (nerve cells) in the temporal lobes compared to healthy controls. Again, these brain regions are associated with the ability to control sexual behavior.
- PHB subjects had weaker connections between parts of the brain associated with the ability to shift attention: the precuneus and temporal cortex. Discussing the importance of this finding, the researchers stated: “Studies on addiction have reported that participants with addiction have problems with attention shifting, and that this behavioral characteristic is related to altered activation of the precuneus.”
- PHB subjects had reduced connection between parts of the brain that help control impulses called the left superior temporal gyrus (STG) and the right caudate. Even more telling, the study found that the PHB subjects who reported the greatest difficulty in controlling their sexual behavior had the weakest connections. The researchers pointed out that this brain change is related to addiction: “A negative correlation was also observed between the severity of PHB and functional connectivity between these areas…The caudate nucleus is the main subregion of the striatum, and is important for reward-based behavioral learning, intricately associated with pleasure and motivation, and related to the maintenance of addictive behaviors.”
These findings provide evidence that those who struggle to control their sexual behavior and pornography use suffer from an addiction-related brain change called hypofrontality. It can result in poorer decision-making. Frontality refers to the frontal (in this case temporal) brain lobes. Hypo means that these lobes are functioning below normal.
Thanks to technological advances and studies like this one, brain scientists are able to see what ”problematic hypersexual behavior” looks like in the brain. To many experts… it looks like addiction.
