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For better or worse, the internet brings people together from distant corners of the world, and has information on every conceivable topic. And, of course, that includes porn.

There's some debate about how much of the internet is actually pornographic content. But if you look for it, you'll find it. So how does it affect people's brains, attitudes, and behaviors?

The short answer is, it's complicated, and there's a lot we don't know. But we have studied some of the risks—and yes, even possible benefits—of watching pornography. So you know, some of these studies talk about disturbing behaviors like sexual violence and rape.

Just in case you would like to avoid those things. Most research on pornography is correlational. There aren't volunteers who get randomly assigned to watch a bunch of explicit videos to see what happens to their brains.

Instead, lots of studies involve surveys, asking people about their behaviors and traits, in addition to how much porn they watch. On top of that, everyone who participates needs to consent to being in a study about pornography, which might mean some people self-select out of this. All that to say: we can't be sure if these findings apply to everyone or even most people, but they're a start.

Some research has found that watching a lot of pornography might reflect differences in people's brains, especially in a part called the striatum. The striatum is involved in reward processing, and consistently gets activated during sexual arousal—among other regions. Sexual arousal is a workout for a lot of your brain.

Two MRI studies tested about 70 male participants by showing them sexy pictures. And the men who felt their pornography use was addictive or problematic had more activity in the ventral striatum compared to those who didn't. Another study found that how much porn men watched was negatively correlated with the size of a part of the striatum called the right caudate, as well as the connectivity between the striatum and other parts of the brain.

The researchers of that last study say it's possible that people who watch a lot of pornography stimulate this reward system a lot, and actually rewire their brain to need more stimulation. But they also note that these brain differences might not be caused by porn. In other words, people with a smaller striatum may need more stimulation to experience pleasure, and seek out more pornography.

With this kind of correlational research, you can't really tell which of the two it is. Another question that comes up a lot is whether viewing pornography can be cathartic— basically, a safe outlet for certain emotions. For instance, psychologists have tried to study how it affects aggression.

If you look at the general pattern across the U. S., as pornography has become easier to access over the past few decades, rates of violent crime like rape have gone down. And there's a similar pattern if you look at when pornography has become widely available in other countries, too.

But, like we mentioned before, this is just a correlation and not all studies show this link. For example, a 2016 meta-analysis in the Journal of Communication looked at 22 different studies that asked people about their porn viewing and self-reported sexual aggression— things like using force, verbal harassment, or other threatening behaviors. And they found that more porn viewing was related to higher levels of verbal and physical sexual aggression, particularly if the porn had violent content.

This suggests that behavioral modeling might be at work: that people who see a behavior in others—even on a screen—are more likely to do it themselves. So psychologists have tried to make sense of these contradictory data. One 2012 study published in the Journal of Criminal Justice might help shed some light: the relationship between porn and aggression could have to do with timing.

The researchers asked over 600 adult men who were convicted of sex crimes about their history of watching pornography. They found that regularly watching pornography during adolescence was linked with more severe crimes committed as adults, including more humiliation of their victims, so maybe early exposure to aggressive sexual behavior played a part in that. And if the convicts had reported viewing porn just before their offense, their crimes were less severe, so catharsis may have been involved.

But there are also lots of factors that lead to violent crime. So, again, without causal evidence, we don't know if or how pornography is directly linked. Plus, the sample sizes of studies like that are relatively small, because most people don't commit violent crimes.

It's a little easier to measure something like sexism, since anyone can report their attitudes about men and women. And do, all the time. It's the internet.

According to two studies published in the Journal of Sex Research in 2015 and 2017 that looked at the habits of tens of thousands of Americans, using pornography is associated with more egalitarian views—things like wanting women in the workplace and in positions of power. But the story is different when it comes to rape myths, like the idea that what someone's wearing can excuse violence against them. Surveys of hundreds of college students have found that men and women who view porn—especially violent porn—are more likely to believe rape myths.

Finally, when it comes to your overall well-being, several studies suggest that whether porn is good or bad for you may depend on whether you think it is. One study of over 2000 people found that watching porn was linked with an increase in self-reported symptoms of depression. But that effect was mainly seen in the 10% who watched despite their moral opposition to it.

The researchers supposed that those people were distressed by the dissonance between their moral ideals and their actions. For those who weren't morally opposed, only the people who watched pornography, like, several times a week or more reported more symptoms of depression. And the researchers figured the opposite could be happening here: these people may be depressed and using porn to cope.

So there do seem to be some risks associated with watching a lot of pornography, but it might not be all bad. More than anything, we need more research to really know if and how much it affects us. Because psychology, and the human brain, and our behavior?

It's complicated. Thanks for watching this episode of SciShow Psych! If you want to and have the means to support us as we cover these trickier questions about the human mind, consider heading over to patreon.com/scishow and becoming one of our patrons!

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