Yeah, correlation and causality are 2 different things, which is why it would be interesting to see some research on the subject.
What the first poster mentioned is another thing that interests me, and that is the role of the right-brain. It’s been a long time since I’ve read about it, but I know that there is a region of the brain that is involved in “spirituality”, which is also the part of the brain involved in both schizophrenia and mind-altering drugs. Sort of the euphoria part of the brain.
I know that when porn addiction is involved there is a need for more and more bizarre stimulation to get the same effect, which is why some people who use porn go on to SM, bestiality, rape, murder, etc. Their mind gets numb to the effects and they have to do more animalistic things to get the high/euphoria they want. So it really is like a drug - except that it requires another person or animal to be the apparatus for satisfaction (the objectification of another person). And I wonder if it involves the same part of the brain.
If so, then what happens in the brain for at least some people who use porn could be on the spiritual level, clinically speaking. Deeper to a person’s inner being than any other physical body function. Know what I mean? Your comparison to a gun is interesting too, because for some people there is a high from killing - in which case, the gun becomes the means to get the feeling of euphoria, which could also be centered in that same “spiritual” part of the brain.
IOW, I’m wondering if the feeling of euphoria can be an attempt to fill a spiritual void - a thrill to substitute for something spiritual. I’m wondering what the science would say about that, if anything. I wonder if it would say there is a different brain reaction for somebody who looks at porn casually versus somebody who is addicted to it.
As the first poster mentioned, I think porn does have an impact on male-female relationships because it changes the expectations and the mind of the person, where the pleasure itself can be the focus rather than the person. Where the person can become simply a means to an end. I think that’s why men are more drawn to porn than women are - because it caters to the more non-relational sex drive of a man, rather than the relational drive of a woman.
I've heard and/or read interviews with incarcerated pederasts, rapists, etc., where they readily admit that if released, they would continue to commit the crimes for which they were incarcerated. And while that sounds incredulous (e.g., you mean, you didn't learn your lesson), it's not really beyond the pale when you consider that those crimes make up their sex drive, which is one of the strongest human impulses of all. Imagine how difficult it would be for the rest of us if garden-variety heterosexuality were criminalized?
Add to that the brain chemistry stuff that you discuss in your post, and the picture becomes a bit more clear: the combination of the natures of addiction and sex drive . . . talk about crossing the streams of some powerful forces.
Purely from an anthropological standpoint, it's going to be interesting to see what impact readily-available pornography has on today's children when they become adults.