Your Brain on Porn (11 page)

[72]
This neurochemical reality primes young brains. They learn to define sex according to whatever stimuli offer the biggest sexual buzz.

Adolescents wire together experiences and arousal much faster and more easily than young adults

will just a few years later. The brain actually shrinks after age 12 as billions of nerve connections are pruned and reorganized. The use-it-or-lose-it principle governs which nerve connections survive.

Once new connections form, teen brains hold tightly to these associations. In fact, research shows that our most powerful and lasting memories arise from adolescence – along with our worst habits.

Before 24/7 streaming porn, the usual sexual cues were other teens, or an occasional centrefold,

or maybe an R-rated movie. The result was pretty predictable: Peers were a turn-on. Now, however:

I'm 25, but I've had highspeed internet access and started streaming porn videos since
age 12. My sexual experience is very limited and the few times I've had sex have been total

disappointments: no erection. Been trying to quit for 5 months now and finally have. I realize
that I've been conditioned to the point where my sexual urges are deeply linked to a computer

screen. Women don't turn me on unless they are made 2-D and behind my glass monitor.

Especially in an overactive adolescent brain, such unconscious wiring can lead to unexpected shifts in sexual tastes. Once again, as psychiatrist Norman Doidge explained in
The Brain That
Changes Itself,
‘Because plasticity is competitive, the brain maps for new, exciting images increased at the expense of what had previously attracted them’
.

If the majority of a teen's masturbation sessions are porn-fuelled, then brain maps related to Jessica in algebra may be crowded out. Spending years before your first kiss hunched over a screen with 10 tabs open, mastering the dubious skills of learning to masturbate with your left hand and hunting for sex acts your dad never heard of, does not prepare you for fumbling your way to first base, let alone satisfying lovemaking.

Fortunately, brain plasticity also works the other way. I see many young guys quit porn and, months later, realise that the fetishes they thought were indelible had faded away. Eventually, they can't believe they once got off to X (and perhaps
only
to X).

Adolescent sexual conditioning likely also accounts for the fact that young men with porn-induced erectile dysfunction need months longer to recover normal sexual function than older men do. This might be because the older men did not start out wiring their sexual response to screens, and still possess well developed ‘real partner’ brain pathways, or brain maps. Typically they had reliable erections with partners for years before they met highspeed tube sites.

Addiction

A second adaptation that may arise from excessive porn consumption is
addiction
. Interestingly, scientists recently showed that methamphetamine and cocaine hijack the
same reward-centre nerve
cells
that evolved for sexual conditioning.
[73]
A second study by some of the same researchers found that sex with ejaculation shrinks (for a week at least) the cells that pump dopamine throughout the reward circuit. These same dopamine-producing nerve cells shrink with heroin addiction.
[74]

Put simply, addictive drugs like meth and heroin are compelling because they hijack the precise

mechanisms that evolved to make sex compelling.
[75]
Other pleasures also activate the reward centre, but their associated nerve cells don't overlap as completely with sex. Therefore they feel different and less compelling. We all know the difference between munching on chips and an orgasm.

Just as drugs can activate the ‘sex’ nerve cells and trigger a buzz without actual sex, so can internet porn. Pleasures like golf, sunsets and laughing cannot. For that matter, neither can good old rock & roll. Just because something is pleasurable doesn't mean it's addictive. Sexual arousal is nature's number-one priority and raises dopamine the highest of all natural rewards.

Researchers know that in all addictions, despite their differences, chronic dopamine elevation tips specific neurochemical dominoes, which bring about an established set of core brain changes.

[76]
These, in turn, show up as recognized signs, symptoms and behaviours, such as those listed in this standard addiction assessment test known as the ‘Three Cs’
[77]
:

1.

craving
and preoccupation with obtaining, engaging in or recovering from the use of the substance or behaviour;

2.

loss of
control
in using the substance or engaging in the behaviour with increasing frequency or duration, larger amounts or intensity, or in increasing the risk in use and behaviour to obtain the desired effect; and

3.

negative
consequences
in physical, social, occupational, financial and psychological domains.

How great is the risk of porn addiction? Well, it's common knowledge that dopamine-raising substances, such as alcohol or cocaine, can create addictions. Yet only about 10-15% of humans or rats that use addictive drugs (except nicotine) ever become addicts. Does this mean the rest of us are safe from addiction? When it comes to substance abuse, perhaps
yes
.

Yet when it comes to unrestricted access to superstimulating versions of natural rewards, such as junk food
,[78]
the answer is
no
,
[79]
although certainly not every consumer gets hooked.

The reason that highly stimulating versions of food
[80]
and sexual arousal can hook us – even if we're not otherwise susceptible to addiction – is that our reward circuitry evolved to drive us toward food
[81]
and sex, not drugs or alcohol. Today’s high fa
t[82]
/sugar food
s[83]
have hooked far more people into destructive patterns of behaviour than have illegal drugs. 70% of American adults are overweight, 37% obese
.[84]
We don't know how many people are being negatively affected by internet pornography, given the secrecy that surrounds its use, but the parallels with junk food are both highly suggestive and deeply troubling.

These supernormal versions of natural rewards have the ability to override our brain’s satiation

mechanisms – the ‘I’m done’ feeling.
[85]
It's hardly surprising that unlimited erotic novelty is compelling for large swaths of the population, including many who would not be susceptible to substance addiction.

I do occasionally drink but not too much. I have no addictions except porn. I grew up
thinking it was a normal thing and that everyone does it. I thought that it might even be good
for me.

*

I battled with porn addiction for years, whereas quitting smoking was a single decision
and I never looked back. Unlike smoking, porn addiction is tied to an underlying biological

need, which merges with the addiction and makes everything more difficult.

Are We
Really
Talking About Addiction Here?

Some psychologists and clinicians outside the addiction-neuroscience field claim it is a mistake

to employ addiction science to understand behaviours like compulsive gambling and out of control consumption of internet pornography. They argue that addiction only makes sense when talking about substances like heroin, alcohol or nicotine. This view often finds its way into the media. But the latest research into the nature of addiction contradicts this. You may not be aware of it but addiction is perhaps the most extensively studied mental disorder. Unlike most disorders in psychiatry's bible, the
Diagnostic and Statistical Manual
(
DSM-5
), addiction can be reproduced at will in laboratory animals. Researchers then study the causal mechanisms and resulting brain changes right down to the molecular level.

For example, they have discovered that same molecular switch (protein DeltaFosB) initiates key

addiction-related brain changes (and thus behaviours) in both chemical and behavioural addictions.

[86]
These kinds of discoveries are the reason that addiction experts have no doubt that both behavioural and substance addictions are fundamentally one disorder.

Already, some seventy brain studies on internet addicts reveal the presence of the same core brain changes seen in substance addicts
.[87]
If internet use itself is potentially addictive, then obviously internet porn use is too. Indeed, in a study entitled, "Predicting compulsive Internet use: it's all about sex!" Dutch researchers found that online erotica has the highest addictive potential of all online applications (with online gaming second).
[88]
This makes perfect sense because addictive drugs only cause addiction because they magnify or inhibit brain mechanisms
already in place for natural
rewards
, such as sexual arousal
.[89]

In other words, existing internet-addiction brain studies (many of which include internet porn use
[90])
already indirectly establish the addictiveness of internet porn as a matter of hard science.

As yet, only two studies (both published in 2014) have isolated and analysed the brains of internet porn users. The first of these looked at users who were not addicts: "Brain Structure and Functional Connectivity Associated With Pornography Consumption: The Brain on Porn". It was published in the prestigious
JAMA Psychiatry
journal
.[91]
In this study, experts at Germany's Max Planck Institute found:

1.

Higher hours per week/more years of porn viewing correlated with a reduction in grey matter in sections of the reward circuitry (striatum) involved in motivation and decision-making. Reduced grey matter in this reward-related region means fewer nerve connections.

Fewer nerve connections here translates into sluggish reward activity, or a numbed

pleasure response, often called
desensitisation
(more on that below). The researchers interpreted this as an indication of the effects of longer-term porn exposure.

2.

The nerve connections between the reward circuit and prefrontal cortex worsened with

increased porn watching. As the researchers explained, ‘Dysfunction of this circuitry has been related to inappropriate behavioural choices, such as drug seeking, regardless of the

potential negative outcome.’ In short, this is evidence of an association between porn use and impaired impulse control.

3.

The more porn used, the less reward activation when sexual images were flashed on the screen. A possible explanation is that heavy users eventually need more stimulation to fire

up their reward circuitry. Said the researchers, ‘This is in line with the hypothesis that intense exposure to pornographic stimuli results in a downregulation of the natural neural response to sexual stimuli.’ Again, desensitisation is common in all kinds of addicts.

To sum up: More porn use correlated with less gray matter and reduced reward activity (in the dorsal striatum) when viewing sexual images. More porn use also correlated with weakened connections to the seat of our willpower, the frontal cortex.

Keep in mind that this study did not examine causation, but rather correlation. The researchers analysed the brain scans of 64 porn users in relation to a ‘pure dosage effect of porn hours’. None were addicts. The scientists also carefully screened potential subjects to exclude people with other medical and neurological disorders as well as substance use.

However, the researchers didn't take the next step of having subjects remove porn use for months

to see if the changes reversed themselves. Nevertheless, extensive related research (some of which has recorded improvements after quittin
g[92]
) supports the hypothesis that chronic overstimulation is the culprit. Lead researcher Kühn told the press that the results ‘could mean that regular consumption of pornography more or less wears out your reward system.’

A forthcoming series of studies by Cambridge University addiction neuroscience experts isolated

actual internet porn
addicts
and examined their brains
.[93]
The first of the series has been published, and the lead researcher said:

There are clear differences in brain activity between patients who have compulsive sexual

behaviour and healthy volunteers. These differences mirror those of drug addicts’
[94]
… I
think [ours is] a study that can help people understand that this is a real pathology, this is a
real disorder, so people will not dismiss compulsive sexual behaviour as something

moralistic. ... This is not different from how pathologic gambling and substance addiction
were viewed several years ago.
[95]

The Cambridge team discovered that, in addicts, the reward centre (nucleus accumbens) showed

hyper-reactivity to porn cues (hardcore video clips). This is evidence of
sensitisation,
explained more fully below, which powers cravings in addicts. Incidentally, women porn users also recorded

increased cue-reactivity (as compared with controls) in a recent German study.
[96]

In contrast, when the Max Planck team (above) looked at
non
-addicted porn users' brains they found less activation of
another
region of the reward circuit. This is evidence of
desensitisation,
or a numbed responsiveness.