I came across this article about Medical Myths Even Doctors Believe. I thought it was interesting reading. That common belief in particular about "we only use 10% of our brains" always seemed like bovine fecal matter to me, and this article specifically mentions that belief. Just like my previous post on "Does Watching TV Really Cause Short Attention Spans?", I've always figured that statement about unused brain capacity has never really been put through the wringer of critical thinking. It's just been parroted throughout the years, even by doctors on PBS and Discovery Channel shows.