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This week we’re running a four-part series about the effects of pornography on the brain. The first step in understanding these effects is to understand the relationship between your noodle and dopamine, and how this interplay makes the pull of porn so strong. I truly feel that understanding this dynamic is the crucial foundation to making a decision about what role you want porn to play in your life, and also to ultimately quitting this habit. So I’ve made this and tomorrow’s post fairly in-depth. But I have also kept the info very accessible, and I think those who read the articles in their entirety will find them worthwhile. But if that’s simply not for you, feel free to skip to the recap at the end.

Dopamine and Your Brain

Our brains are composed of billions of cells called neurons that send messages to each other through an electrical-chemical process. Without getting too technical about how this works, the important thing to understand for this discussion is that the neuron delivering the message releases a chemical called a neurotransmitter into the synapse – the space between the neurons — and over to a receiving neuron. The receiving neuron catches the neurotransmitter with its receptors and then generates electricity so it can communicate to another neuron. This process repeats itself a bajillion (that’s a scientific term) times a day.

Different neurotransmitters communicate different things. What they all have in common is that their primary purpose isn’t to make you “happy” or fulfilled, but to ensure that your carcass survives so that you can pass on your genes.

An integral part of our brain’s system for increasing our chances of survival and reproduction is creating the strong desire and drive to do or seek out those things that will help us fulfill those aims. We have to want to eat, we have to want to seek shelter, and we have to want to have sex. The neurotransmitter that gives us our drive to fulfill these impulses is dopamine.

Dopamine is released whenever we encounter rewards, or “natural reinforcers,” that help us survive. Things like food, sex, novelty (new things may lead to new survival-boosting benefits), and friendship (you’re more likely to survive in a group) sit at the top of the natural reinforcer hierarchy. Once we encounter one of these potent rewards/reinforcers, a neural pathway is created (more on neural pathways below). Dopamine keys in on the reward system in our brain, and drives us to repeat the same behaviors that helped us attain those rewards previously.

The more something helps with our survival and reproduction, the bigger the “squirt” of dopamine our neurons experience, and the stronger the drive to repeat the behavior. For example, different types of food release different levels of dopamine. Because our hunter-gatherer ancestors lived in feast and famine mode, it made evolutionary sense to load up on as many calories as possible while the getting was good. Foods high in fat and sugar provided the most energy benefits, so our ancestors’ brains evolved to release a lot of dopamine when they encountered high fat and high sugar foods. Our brains continue to do the same thing in the modern word, which explains why when given the choice between a Five Guys burger and a dry salad, our gut instinct is to go with the burger and shake. Dopamine drives us towards sweet, carby, and high fat foods.

Sexual stimulation and orgasm give our brain’s reward system the biggest natural shot of dopamine of all. Which makes sense. From an evolutionary perspective, the entire measure of our creation is to reproduce and pass on our genes. So seeking for and wanting sex should be our primary evolutionary drive. That big dopamine shot that results from orgasm then goes on to wire our brain’s reward system to repeat whatever behavior we did to get sex so we can continue to get sex in the future.

Isn’t Testosterone Responsible For My Sex Drive? Contrary to popular belief and cheesy internet ads, it isn’t testosterone that plays a central role in a man’s sexual libido and ability to get an erection, it’s dopamine. Testosterone plays more of a supportive role in our sex drive by stimulating the brain to produce more dopamine. So while low T can result in low libido, it’s because there isn’t enough T to stimulate sufficient dopamine for a healthy sex drive. It is therefore possible for a man to have high total and free testosterone levels, but low dopamine (or blunted dopamine sensitivity – more on that later), and thus a low or absent sex drive. Testosterone’s dopamine-stimulating abilities also explain why testosterone replacement therapy companies advertise that increasing your T can give you more energy and drive to do other stuff in life. It’s not the T itself, but rather the dopamine that T triggers in the brain that gives you that boost. The more you know.

The release of dopamine starts amping up your sex drive when you see someone attractive. This increase will motivate you to do whatever your culture says you need to do to woo that person and eventually get them into bed. If you’re the old-fashioned type, that process can take a while. If you’re a Don Juan and the gal is open to casual sex, maybe a few hours is all you’ll need. Whatever the timetable, dopamine levels and hence sex drive will continue to increase as you move towards consummating your desire. The powerful urge to copulate created by spiking levels of dopamine as you get closer and closer to actually having sex partly explains those moments when people say, “I don’t know what happened. One moment we were on the couch watching Louie and the next minute we were making the beast with two backs.”

Once we achieve whatever reward dopamine was driving us towards, the levels of this neurotransmitter drop off. With sex, dopamine levels peak right around the moment of orgasm (to help wire our brains to seek out sex again in the future), but then decrease afterwards because we’ve accomplished our biological imperative to spread our seed. (Your brain doesn’t know if your seed never made it past the end of your condom. As far as your neurons are concerned, it’s “mission accomplished.”) The post-coitus drop in dopamine partly explains the male “refractory period” after sex. (In case you didn’t know, after a man orgasms, it’s physiologically impossible for him to have another orgasm for a period of time. Could be minutes, could be days. Depends on the guy.) When we orgasm, a hormone called prolactin is released which represses dopamine. No dopamine, no sex drive, no boner.

Porn, Novelty, and the Coolidge Effect

Remember when I mentioned above that one of our evolved natural reinforcers is novelty? Our brains are hardwired to seek out novelty because new things can provide survival and reproductive advantages. Whenever we encounter anything new — a new email, a new gadget, a new food — we get a shot of dopamine, which makes us want to look for more new things. We’ve all got an irrepressible treasure hunter streak in us. Thanks to a process called habituation, the familiar just doesn’t provide the same kind of dopamine hit as the novel. Habituation explains why the new car that we were so motivated to get for months and months doesn’t excite us nearly as much after just a few weeks of driving it around town.

We also get that shot of dopamine whenever we encounter a new attractive woman other than our current partner. Our brains are hardwired to seek out as many different (novel) sexual partners as possible. Again, from a reproductive perspective it makes sense that being exposed to a variety of attractive sex partners would jack up dopamine in our sexual reward circuitry, particularly in men. For males, the goal is to reproduce with as many different females as possible to create as many progeny as possible, with as much genetic variation as possible to increase our possible blood lines.

This drive for multiple new sex partners even when you already have an available and willing one is often called the “Coolidge Effect” after a conversation the president supposedly had with his wife:

The President and Mrs. Coolidge were being shown [separately] around an experimental government farm. When [Mrs. Coolidge] came to the chicken yard she noticed that a rooster was mating very frequently. She asked the attendant how often that happened and was told, “Dozens of times each day.” Mrs. Coolidge said, “Tell that to the President when he comes by.” Upon being told, President asked, “Same hen every time?” The reply was, “Oh, no, Mr. President, a different hen every time.” To which the president replied, “Tell that to Mrs. Coolidge.”

To understand the power the Coolidge Effect has in increasing dopamine levels let’s take a look at two experiments.

In the first, a lucky male rat was placed in a cage with four or five female rats. He immediately had sex with all of them until exhaustion. Panting and rolled over in a sexual stupor, the male rat was nudged and licked by the female rats to keep going, but he didn’t respond. The tuckered-out rodent was no longer interested in doing the deed. But as soon as the researchers put a new female rat in the cage, old Mr. I’m Too Tired became alert and sarged over to have sex with the new female, while still ignoring his old harem. This rat’s ability to have sex with a new female despite having been previously sexually satiated all came down to dopamine. The first crew no longer gave him those potent dopamine squirts because, well, they were now boring. Been there, done that. But the new female caused an uptick in dopamine due to novelty and bam! the male rat’s sex drive was back. The Coolidge Effect explains why people are tempted to cheat, even with someone significantly less attractive that their long-term partner; the pull of novelty, any novelty, can be quite strong.

A similar experiment was done to show the Coolidge Effect in humans. Instead of putting a lone man in a room with four or five different women to have sex with (there likely would have been plenty of volunteers, but the ethicality would have been questionable), researchers showed test subjects an erotic film while their penises were attached to monitors to measure arousal. After 18 viewings of the same film, arousal had decreased dramatically. These guys had gotten used to seeing the same woman having sex with the same dude, so dopamine levels dropped. But on the 19th and 20th viewings, researchers showed a new clip and atten-hut! arousal skyrocketed once again. Sexual novelty increased dopamine levels, which increased sexual arousal.

How Online Porn Has Changed Your Brain

Alright. So what does all of the above have to do with internet porn?

Well, dopamine plays a central role in why you want to look at porn. Understand how dopamine works, and you understand why you are attracted to porn.

Porn is a substitute for actual sex, but your brain doesn’t know that. It reacts to a picture of a naked woman or a video of people having sex the same way it does a real life naked woman or you actually having sex. When encountering sexual images, your brain is going to ramp up dopamine levels, driving you to orgasm — whether that climax is fostered with another human being or is self-induced.

Dopamine also explains why certain types of porn are more compelling than others, and how in extreme cases men prefer porn to actual sex.

A still picture of a naked woman will jack up dopamine levels the first time you see it, but after a while that same picture just won’t do it for you any more. Your brain has become habituated to that stimulus. In order to be aroused again, you’d need to increase dopamine levels by injecting more novelty into your sexual fantasies with a new picture of a different naked woman.

But as time goes on, simply looking at any picture of a naked woman won’t get you aroused. You need something more. Well, you get a bigger squirt of dopamine whenever you watch others have sex in a porn video because the live action activates your mirror neurons, making you feel like you’re the one having sex. The stronger the stimulation, the bigger the shot of dopamine to the reward system, and hence the greater desire you have to watch that porn video.

But as the study above showed, after repeated viewings, even an erotic film can become like watching a boring documentary. It just won’t offer the same kind of dopamine hit you got the first time you watched it, and will eventually fail to arouse you. Again, this is due to habituation. To become sexually aroused again, you need to increase dopamine levels by watching something new, be it a video with a new woman or a video with some new sex practice you’ve never seen before. Add the novelty, increase the dopamine, and sexual arousal returns.

You’re probably seeing a common theme here: novelty. Porn offers the sexual novelty that dopamine has hardwired you to seek. The more you successfully find new sexual experiences, the more dopamine you get, which reinforces the desire to look for even more sexual novelty. Porn’s easy access to new “experiences” is part of what makes it so alluring.

Now before the internet, this wasn’t much of a problem. Once a man in the pre-internet porn years got habituated to his “girly” magazine, he had to trek over to the adult bookshop or the convenience store in the seedy part of town to get a new one. If he wanted to watch a pornographic film, he’d have to go to a XXX theatre or maybe a porno booth in that bookstore where he got his mags. Whether getting magazines or seeing films, it was a lot of rigmarole to get porn, plus there was the risk of getting caught and experiencing social shame. So, many men just didn’t bother. Even when he could have the magazines or videos delivered to his home, that happened maybe once or twice a month. If he had kids, he had to find a place to stash his porn and then find time when his family wasn’t around so he could exhume his collection and view it in privacy. Again, a lot of rigmarole.

So while porn offered some sexual novelty back in the day, there were barriers put in place due to technology (or the lack thereof) and social mores that made access to new and novel porn difficult and time-consuming. Because the dopamine hits from the new and novel didn’t come easy, getting hooked on porn was difficult and most men didn’t experience the many problems that modern porn users report.

Fast-forward to today. Thanks to the internet, you now have an infinite variety of porn on tap 24/7. Dopamine spikes due to sexual novelty have never been easier to achieve. No more trudging to the adult bookstore, no more going to great lengths to hide your porn. Just bring it up on your laptop or mobile device in the privacy of your home or at the bathroom at work. You can have multiple tabs open in your browser for different porn sites featuring a whole host of different virtual sex partners. As Gary Wilson notes in Your Brain on Porn, in “ten minutes, you can ‘experience’ more novel sex partners than your hunter-gatherer ancestors experienced in a lifetime.”

Internet porn doesn’t just provide access to novel sex “partners,” but to novel sexual experiences as well. You’re not just limited to watching a couple have sex missionary style, but can watch a wide variety of sexual acts. Just as novel sex partners will jack up dopamine levels, so will observing different sex acts. And as we’ll discuss tomorrow, dopamine levels also spike when we encounter things that shock us or gross us out. The more intense the emotional experience we have when we encounter porn, the more dopamine is released into our brain’s reward system. Which is why you may find yourself searching for kinkier and kinkier porn even though part of you finds it repulsive. All of this novelty is just a click away. As you experience more and more dopamine squirts to your reward system with new types of porn, connections in your brain’s reward circuitry strengthen, increasing your drive to seek even more sexual novelty. On and on the cycle goes.

Neuroplasticity, or, Why You Have the Urge to Look at Porn Whenever You Get Bored or Open Up Your Web Browser

So dopamine is what drives you to want to look at porn. And thanks to the internet, you have access to an unlimited variety of sexual “experiences” that when viewed, send out squirt after squirt of dopamine in your brain, which drives you to search for more and more porn.

At the same time, without you even knowing it, those dopamine squirts are also strengthening neural connections that are responsible for the behavior that keeps those neurotransmitter hits coming.

Porn is literally rewiring your brain.

You’ve probably heard the phrase “neurons that fire together, wire together.” It aptly describes the way we learn things. Everything you know – how to walk, how to throw a football, who won the World Series in 1989 — is made up of connected neurons firing in sync with one another. The stronger the connection, the less you have to think about doing or remembering the thing you’re trying to recall. You don’t have to think about walking, for instance, because the neurons involved in walking have a strong connection that began being formed as toddler. However, trying to remember information for a history test that you just crammed for the previous night might be more difficult because the neurons involved in that memory haven’t fired enough together to create a strong connection.

Neurons firing and wiring together is also how our habits are formed. When you receive a shot of dopamine after receiving some reward, be it food or sex or novelty, your brain is strengthening the neurons that fired and wired together to achieve the reward so that you will repeat the process and can get it again in the future. This rewiring involves connecting the cues and behavior that led to a respective reward.

This cue-behavior-reward connection is what author Charles Duhigg calls “The Habit Loop,” and understanding it can go a long way in helping you understand your porn habit (and break it).

Habit researchers have shown that almost all cues (the thing that reminds or triggers your brain to seek a reward through a certain behavior) fall into one of five categories:

Location

Time

Emotional State

Other People

Immediately-preceding Action

Again, your brain is paying attention to cues that are connected with the reward. Once it recognizes the cue, dopamine is released to get you craving and wanting to do whatever it takes to get the reward. Think Pavlov’s dogs here. At the beginning of that experiment, it was just food that got the dogs salivating. But then they were introduced to the cue of a metronome, and after a while just that sound would get them salivating for their reward.

With porn, the associated cue could be sitting down at your computer late at night when everyone else is asleep. If you’re John Mayer, the cue would be being in bed when you first get up in the morning. For many guys, being in bed right before they go to sleep is a cue. Coming across a porn image by accident while surfing Tumblr could be a cue to start looking for more porn. Heck, just visiting Tumblr might be a cue to start looking for more porn.

Cues don’t even have to be external. The most common porn surfing cues are emotional states. Many men find themselves surfing for porn when they’re depressed or bored or even distracted. For them, the pleasure of porn offers relief from these unpleasant emotions.

Once the cue triggers the dopamine production that ramps up your motivation to view porn, a behavioral routine is automatically set in motion. A routine is a behavior or set of behaviors that get you to the reward of orgasm. So let’s say your cue to look for porn is when you’re at your computer late at night after everyone has gone to bed. Once that happens, without even really thinking about it, you open up your web browser (in incognito mode, of course) and go right to PornHub to commence a session of porn browsing and masturbating. The cue-behavior/routine-reward circuit is complete. Your brain releases a huge squirt of dopamine right around orgasm, reinforcing the neural connections associated with the cue, routine, and reward so that next time you have the same cue (at your computer late at night), you’ll get that itch to start your routine to get more porn. Repeat this circuit over a period of a few days or weeks, and you’ve got yourself a strong neural connection that leads to you checking out porn without even really thinking about it. That’s how porn can become a strong habit or even an addiction (we’ll talk more about the habit vs. addiction distinction in the next post).

Recap

Let’s review what we’ve covered today.

The reason porn is so alluring is because of dopamine. Dopamine is what makes us crave or seek out evolutionarily advantageous rewards. Sex is the strongest natural reinforcer of behavior and releases the most amount of dopamine in our brain when we successfully orgasm. Our brain doesn’t differentiate between porn-induced sex fantasies and actual sex, so we get the same big squirt of dopamine, and the same incredibly strong drive to orgasm, with porn as we do with real life sex. Basically, when you look at porn, your brain thinks you’re a heroic tribesman out on the savanna, and is shouting “Atta boy! Spread that seed! Spread that seed!” when in reality you’re hunched over your laptop, the light of the screen illuminating your dead-eyed gaze, as you clench a wad of tissues.

The more habituated we get to a stimulus, the less dopamine our brains release in conjunction with it. Getting the same hit as before necessitates seeking out sexual novelty, and high-speed internet porn provides this in spades. This easy access to a wide variety of new sexual scenes and practices makes internet porn all the more alluring and desirable thanks to the dopamine hits your brain gets every time you click over to a new porn clip or picture.

Not only does dopamine create the craving to surf for porn, it’s also strengthening the neural connections in your reward circuitry that are responsible for the behaviors that lead to you actually looking at and masturbating to porn. Your brain comes to associate certain environmental or internal cues with the reward of orgasm so that whenever you encounter these cues, a behavioral routine is initiated that leads you to your favorite porn site. Your brain releases more dopamine in response to successfully getting porn, and orgasming from it, which strengthens this neural cue-routine-reward circuit, making porn surfing a habit that’s extremely difficult to shake.

And there you have the brain science of why internet porn is so incredibly alluring and habit-forming.

But, the question remains…should you even care? Why not just give the old brain what it craves and not worry about it? To the possible negative effects of this course, is where we will turn in part 3.

Read the Other Posts in the Series

Men and Porn: An Introduction

The Possible Pitfalls of Porn

How to Quit Porn

For more information on the science of porn on your brain, make sure to visit YourBrainOnPorn.com

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Tags: men and porn