Pornography has pretty much been around since humans first learnt to draw on cave walls. And until quite recently it has been, at least in this journalist’s opinion, a fairly harmless indulgence for most who consume it and even an occasional sexual aid for some.

But the internet has changed the game. Dramatically.

Over the last few years, a host of large, well-respected publications have run piece after piece on studies conducted by large and highly-esteemed institutions involving the effects of internet pornography on the brain. I mention the size and respectability of the publications and institutions because I don’t want you to dismiss the findings as coming from sex-negative, conservative or religious organisations. But more about that later.

Overwhelmingly the studies seem to suggest that exposure to large amounts of internet porn is tied to loss of libido, erectile dysfunction, inability to climax and – get this – smaller brain sizes.

The studies

Time Magazine published an article around the findings of a study conducted at the Max Planck Institute for Human Development in Berlin, Germany. The study "found a significant negative association between reported pornography hours per week and gray matter volume".

This is something that websites yourbrainonporn.com and fightthenewdrug.org discuss at some length. These organisations see the massive scale and availability of modern-day porn as a public health issue and not a moral, political or religious one.

In 2014 Vice ran an interview with Gary Wilson, the guy behind yourbrainonporn, who, according to The Good Men Project is a teacher of anatomy, physiology and pathology.

So the more porn you watch – the smaller your brain gets and the less sexual arousal you will experience.

Wilson is using data that neuroscientists developed around addiction along with 70 or so studies on how internet addiction affects the brain. In a nutshell, he asserts that porn stimulates surges of dopamine secretion in the brain, and that repeated surges lead to desensitisation and depletion. Combining the material (pornography) with the delivery system (the internet) causes a perfect storm in the brain.

The University of Cambridge also did two studies as The Daily Mail reports, which found that the same kind of brain changes happen in porn users as with drug addicts and those who have been watching porn for longer had less activity in their brains’ reward centres. So the more porn you watch – the smaller your brain gets and the less sexual arousal you will experience.

Yikes.

Watch: The great porn experiment

Of course, not all doctors agree. In a 2013 article in Psychology Today David Ley decries the dopamine theory in favour of another study that was undertaken using electroencephalograms (EEGs), still images and questionnaires. But critics doubt the validity of the findings since they used still images instead of movies and there was a level of subjectivity involved in the form of questionnaires. 

Either way, he seems to be the minority in a major sea of cumulative concern as yet another article in Psychology Today acknowledges that “plenty of people out there, including teens and pre-teens with highly plastic brains, find they are compulsively using high-speed Internet porn with their porn tastes becoming out of sync with their real-life sexuality.”

So even while some doctors and sexologists are refuting evidence that porn consumption works on the same centres of the brain as, say, cocaine addiction, one thing seems to be clear:

Even if porn isn’t changing your brain on an addiction level, it is changing your desires and personality. And I quote Troy Patterson writing for Slate:

“Let’s leave aside the question of whether the stuff rewires your brain and simply say it’s no good for your head.”

The impact

As anyone who regularly watches porn will tell you – it gets boring, pretty quickly. So people become dependent on more and more extreme porn and this German study explains why.

And for me, therein lies the rub.

Let’s face it, porn used to be much milder. Sure you could argue that the naughty nudes from the 20s, the pinups from the 50s, the bikini girls from the 70s Scope years and even the bare naked ladies from a 90s Penthouse or Playboy were objectifying women, but you could also argue that it was a celebration of the female form.

Even hardcore blue movies from earlier decades were softer in tone.

Either way, it’s very far removed from today’s high-speed, extreme, sometimes deviant and often violent sex depicted in scenes. Is it any wonder that young men struggle to get aroused by their real life partners or get angry when women don’t want to engage in some acts that are commonplace in mainstream porn?

Not only has the rate of erectile dysfunction in young men skyrocketed, but many young men report altered sexual tastes and real life intimacy and attachment issues.

Yet another report published in Psychology Today concludes that young men are becoming totally hopeless in the bedroom. Not only has the rate of erectile dysfunction in young men skyrocketed (from just 1% in men under 30 as was found by Kinsey in 1948 to 1 in 4 according to WebMD) but many young men report altered sexual tastes and real life intimacy and attachment issues.

In this article Dr Philip Zimbardo asserts that for men raised on porn, real life sex “can be a foreign and anxiety-provoking experience. This is because communication skills are required, their entire body needs to be engaged and they must interact with another three-dimensional flesh-and-blood person who has their own sexual and romantic needs.”

Needs which are blatantly ignored in most mainstream porn.

Trigger warning: sexual violence

Not only does the most popular internet porn seem to be dependent on humiliating and violating the women who appear in it, but it also makes it look like no matter what a man does, the woman will respond positively. 

Watch: Porn and sexual violence - 10 facts from the experts

And when I say most, I mean most. The Daily Telegraph reports that Australian adolescent sexuality expert and researcher Maree Crabbe, did an analysis of the most popular videos and found that 88% of these scenes included physical aggression, including gagging, choking and slapping. 

There are a host of discussion boards from Reddit to Quora wondering why modern porn has become so cruel and the answers seem to lie in the brain desensitisation theory. It's escalating behaviour. In discussions I've had with many people on the subject, a lot of men (and women) confess that they now get aroused by scenes they would have found disturbing just a couple of years ago.

Troy Patterson for Slate perhaps says it best:

“The degradation of women is a foundational premise of [modern pornography] but what once was latent has become a driving point.”  

What about the children?

Of course I am not saying that rough sex is a male only interest. Of course there are women who enjoy it. Of course consenting adults can perform whatever sexual acts blow their hair back. And of course for many rough sex is a successful fantasy – I mean just look at the success of recent BDSM novels like 50 Shades of Grey. I am not discounting that.

But having constant access to hundreds of thousands of videos is blurring the lines between fantasy and reality. Especially in the teenage brain.

But the mass availability and nature of internet porn is eating away at that.

Wilson reckons “when you’re watching these videos of real people having so called “real” sex it completely replaces the imagination. You no longer imagine what it's like. You become a voyeur watching all this action rather than with a still picture imagining the action you can create.”

Think about it. A 13 year-old boy used to be able to see a girl accidentally flash her knickers when sitting down, or a teacher bending over in a tight skirt, and that would be enough to fuel his imagination and sexual fantasies for weeks.

And imagination and fantasising are not just essential for brain development, they're also key ingredients in great sex. But the mass availability and nature of internet porn is eating away at that.

Now, when the hormones strike, all he has to do is unlock his phone and get online and he will be able to watch what even porn stars now call “extreme sex.” And what message is this sending to adolescent girls?

I'm sorry, but I don't think it's sex-negative to think it’s deviant for boys as young as 11 to think gang bangs, double penetration, choking, slapping and gagging is normal.

Yet, that is what we're teaching them. And we have no idea how far reaching the consequences will be.

But if I had to bet, I would say it's going to be dire.

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