he battle over porn reached a stalemate years ago, with one side arguing that it
degrades women and is therefore a tool of the patriarchy, and the other side arguing
that it promotes sexual license and immorality. You might think that the two sides
would recognize they're on the same side, but politics doesn't work that way. That's
because porn is just a MacGuffin.
The object isn't porn itself, but something else, and whatever that
something was, the two groups were on opposite sides.
Last month American Greatness published an 11,579-word article titled “A Science-Based Case for Ending the Porn Epidemic” declaring that there's now a scientific case for banning pornography. The author says that porn is more powerful than ever, there's an epidemic of it, it reduces fertility, it causes brain damage, it's a public health menace, and it's heading us toward societal collapse.
Porn consists of images of people with extremely large pixels
I skipped over that article when I first saw it, thinking “Pshaw, oh my goodness gracious me, not this stuff again!” or words to that effect. But loads of people have started talking about it, so since this is a science blog, and not being able to find any good porn all week, I thought I'd address the claim that science has shown any such thing.
Porn is boring
The article follows a now-familiar pattern: it tries to reduce an ethical/moral question to a factual one, draws a conclusion from a set of facts, and uses that to support the author's pre-ordained conclusion. Before I start, here's my Official Disclaimer: my position is that porn is incredibly boring and people need to read more science blogs.
I take it as given that a person viewing porn isn't just trying to get pointers to improve their skill in bed. For whatever reason, viewing human mating behavior provides a purely physiological reward. We may be programmed to view porn as a way of refining our idea of what is and isn't sexy, or as a way of testing whether our equipment still works. It might sound counterintuitive, but if it wasn't beneficial for survival in some way, it would be impossible for us to find porn interesting.
Consider, by comparison, that it's impossible to tickle yourself. Nature can and does block the effects of fake stimuli whenever it's beneficial to do so.
Is porn is a public health menace?
There is a scientific consensus, says the author. He compares it to global warming and smoking. The evidence is in, he says. The debate is over, and scientists all agree:
A scientific consensus is emerging that today's porn is truly a public health menace: its new incarnation combines with some evolutionarily-designed features of our brain to make it uniquely addictive, on par with any drug you might name—and uniquely destructive. The evidence is in: porn is as addictive as smoking, or more, except that what smoking does to your lungs, porn does to your brain.
The damage is real, and it's profound. The scientific evidence has mounted: certain evolutionarily-designed features of our neurobiology not only mean that today's porn is profoundly addictive, but that this addiction—which, at this point, must include the majority of all males—has been rewiring our brains in ways that have had a profoundly damaging impact on our sexuality, our relationships, and our mental health.
The infamous “queen takes knight” scene from Mini Royal Chess. It's rated “Not Suitable for children under 3!”
Where have we heard this argument before? We have (1) it's worse now than ever; (2) there's a consensus in science; (3) it's an existential threat to society or life as we know it; and (4) urgent action is needed now. Unfortunately, this is not an argument at all, but an appeal to groupthink.
Anyone who writes research papers and grants knows you can find an article somewhere to back up any hypothesis. String a bunch of them together, ignore the conflicting evidence, et voilà: a consensus is born. If I had ten bucks for each time I've had to strike the phrase ‘converging evidence indicates this or that’ from someone's paper, I could buy a cup of coffee and a nice granite countertop to put it on.
The author says that male programming to reproduce is being manipulated by porn merchants. He calls porn a ‘superstimulus’ because it provides such a wide variety of ‘partners’ that is so appealing that males can't help themselves. Males are helpless against porn, he suggests, because it activates addiction pathways.
Is porn use an addiction?
Males are programmed to seek out the most fertile female. For whatever reason, nature does this by giving us a reward for doing it. Once we find a suitable one that doesn't slug us when we say good morning to her, a new and much more powerful addiction sets in, provided the male's psychological development has progressed enough. This new programming makes us pair-bond with the other person. It's so powerful that it makes us put up with all the noise and aggravation that comes with it, and if we're deprived of the object of our attachment, the pain we experience uses the same reward/deprivation pathways that are mimicked by opioids.
The author makes a good point about similarities between sex and opioids, though it's not clear that porn addiction is any more real than the supposed addiction to television viewing, which we were frantically warned about many years ago. The idea that one could be addicted to TV sounds laughable now, but even if porn users are trying to feed an addiction, wouldn't banning porn just make them switch to some other addictive thing? How is this a good idea?
Does porn really cause brain damage?
The author talks about ΔFosB, which is a truncated form of the protein FosB that is thought to be involved in the reward system in the brain. FosB binds to Jun proteins to form a transcription factor called AP-1. AP-1 induces the expression of proteins involved in cell proliferation. For example, THC induces ΔFosB. The author claims “the release of DeltaFosB that comes with porn use weakens our prefrontal cortex.”
Extreme closeups are common in porn. This is an example, showing a closeup of someone's left nostril. Scientists warn that prolonged viewing of this image could cause massive losses of gray matter
I could find no articles in the medical literature that substantiate this claim. There is one article claiming that sexual arousal decreases the functional synchronization between cortical areas in males and one case report of a patient with frontotemporal dementia who extensively viewed Internet porn. There are also a few scattered reports about white matter deficiencies in pedophiles, but zero articles on frontal lobe gray matter loss caused by porn viewing.
I also found no papers that discussed delta FosB and porn. It would have been remarkable if such a paper existed, because measuring ΔFosB in a human would require obtaining a sample of a person's brain after showing them porn. Good luck getting an IRB to approve that. I conclude that the claim is pure speculation.
The closest I could find was a single article[1] claiming an inverse correlation between gray matter volume in the right caudate nucleus with porn viewing. The caudate has many functions: it's involved in motor control, procedural learning, and inhibitory control of physical action. When dopamine neurons from the substantia nigra are lost, the caudate is where Parkinson's disease symptoms begin. Based on 3T fMRI scans, the authors also claimed that there was an association between porn use and reduced connectivity between caudate and the left dorsolateral prefrontal cortex.
Of course, correlation doesn't mean causation and a single paper in the research literature doesn't prove squat. It certainly doesn't mean porn causes brain damage. The only way to establish this would be with a controlled longitudinal study: take 50 naive subjects, expose 25 (selected at random—very important) to porn, and measure what happens thereafter in their life. Nobody would ever get IRB approval for such a study, but psych researchers have to publish something, which is why we get all these wonderful correlational fMRI studies.
The author also says there are 150 studies showing decreased frontotemporal lobe function (which I guess is what he means) in internet “addicts”, which he says he assumes is “nearly synonymous with internet porn addicts.” There are other studies correlating porn use with narcissism, depression, attachment anxiety, and poor self-esteem. But again, these are all correlations; it's just as likely that lower gray matter increases internet usage.
Also, a decrease in gray matter does not necessarily equate to brain damage. For example, depression is associated with loss of gray matter. It seems to be caused by loss of synapses; unlike neuron loss caused by brain injury, the gray matter is restored by antidepressants.
Now, I don't want to shame the the author for misinterpreting the science research literature. It's admirable that he tries to base his opinion on experimental science. But if we are to ban porn, which is to say to infringe on freedom of speech, which is what the author seems to want us to do, we can't just base it on unsubstantiated assumptions or a few articles pulled out of psych journals. We need to keep these things on a solid scientific basis. If inaccurate claims get widely believed, they become nearly impossible to debunk. If scientists fail to correct them, the claims can delegitimize an entire branch of science.
The internet use = porn = FosB = brain damage theory looks like what scientists call a string of hypotheses, or in other words “a lifetime project,” also known as “job security.”
Porn use is a symptom, not a cause
The evidence seems to suggest that porn use is just a symptom of psychological distress, perhaps an attempt to avoid attachment or compensate for the absence of attachment. If a male college student knows that having sex could get him branded for life as a sex offender, and that getting married means you find a woman you hate and buy her a house (as the joke goes), maybe it even makes sense for him to stick to porn.
If the goal is to find answers, as opposed to stampeding us into banning something we find morally offensive, it must be preceded by a thorough discussion of the issues. We also need to be honest about our reasons, rather than just trying to drag science into it by claiming there is a “consensus” where none exists.
1. Kühn S, Gallinat J (2014). Brain structure and functional connectivity associated with pornography consumption: the brain on porn. JAMA Psychiatry 71(7),827–834. doi: 10.1001/jamapsychiatry.2014.93
dec 28 2019, 7:40 am. edited for brevity dec 28 2019, 1:33 pm. new figures added dec 29 2019, 5:42 pm. last edited jan 02 2020, 5:55 am
