Men who watch a lot of pornography may have reduced activity and lower volume in specific regions of the brain that are associated with motivation and rewards, according to a recent German study.
The study, however, could not prove whether watching porn can lead in brain matter and activity reduction and cannot state it is actually harmful.
The study, published in JAMA Psychiatry, explains that it is not clear whether watching porn can lead to changes in the brain or if people with specific brain types develop the habit of watching more porn, explained Simone Kühn, the study's lead author from the Max Planck Institute for Human Development in Berlin, as reported by Reuters.
"Unfortunately we cannot answer this question based on the results of the present study," said Kühn.
The study results, however, hold to the first evidence of the connection between watching pornography and decrease in brain size and activity in response to sexual stimuli.
For the study, Kühn and her coworker Jurgen Gallinat from Charite University, Berlin, examined 64 healthy men who were in their 21 and 45 years of age and questioned them about their porn-watching habits. They even captured images of those men's brain in order to measure their volume and to observe how the brains responded to pornographic pictures.
"We found that the volume of the so-called striatum, a brain region that has been associated with reward processing and motivated behavior was smaller when more pornography consumption the participants reported. Moreover we found that another brain region, that is also part of the striatum which is active when people see sexual stimuli, shows less activation the more pornography participants consumed," Kühn said.
The researchers while examining the volunteers found that the association between striatum and prefrontal cortex - the outer regions of the brain that is related to decision making and behavior - reduces with increased watching of pornography.
"Everything is going to be bad in excess and it's probably not terrible in moderation. It is possible that there are individuals with a certain kind of brain that are more susceptible to these kinds of behaviors. Or, it's possible it's the excessive use (of porn) that's perpetuating itself to causing brain changes. Or, it could be both." said Dr. Gregory Tau of the Columbia University / New York State Psychiatric Institute in New York.
More research on the study will open up to hypothesis to know if porn really leads to brain changes, said Tau, who was not directly involved in the research.
Apart from brain changes observed from watching porn, other behaviors such as driving a taxi, or reading are also connected to changes in brain functioning and reduction in size. Any excessive activity can affect the brain structure and function, explained Kühn.