A recent study has shown that the brain structures most suited to introspection are more developed in some people than in others. See Relating Introspective Accuracy to Individual Differences in Brain Structure by Stephen M. Fleming, Rimona S. Weil, Zoltan Nagy, Raymond J. Dolan, and Geraint Rees as published in Science (http://www.sciencemag.org/cgi/content/abstract/sci;329/5998/1541).

The same study also showed that introspection can improve with practice and certain processes. Of course, an excellent way to train quality introspective skills is through focused experiential trance and hypnosis. See http://www.briandavdiphillips.com for some excellent resources, courses, and products to help folks do just that and so very much more.

– Brian