Below is a youtube video of a TED talk. It's a great video, about 16 minutes long.  

Have our brains evolved to handle the hyperstimulation of today's Internet porn? The speaker, Gary Wilson, discusses the disturbing symptoms showing up in some heavy Internet users, the surprising reversal of those symptoms, and the science behind it.  

Heavy Internet porn users experience perplexing, unexpected effects: escalation to more extreme material, concentration difficulties, sexual performance problems, radical changes in sexual tastes, social anxiety, irritability, inability to stop, and obsessive-compulsive symptoms. It seems that their symptoms might be the result of addiction-related brain changes.  

Applying the website's concepts of brain plasticity, many former users have braved withdrawal, reversed their symptoms and restored normal sexual responsiveness.  

What is shocking to me is that many guys in their 20's and 30's have erectile dysfunction, primarily because they've been using porn to get off starting at about the age of 14, apparently fucking up your brain and the ability to get stimulated enough to get a hard-on.  

Many "reversal" groups are popping up, with guys trying to not look at porn for 90 days. For those guys that succeed,the  erectile dysfunction problem goes away.

So.... less porn, better erections