Here is a self-link to my meditation blog; this post has links to other posts:

http://meditationstuff.wordpress.com/2013/08/25/how-to-do-foregroundbackground-meditation/

The blog is a mixture of personal experience, unscientific references, and cherry-picked peer-reviewed research. I specifically talk about the dangers of meditation, with included citations, but unfortunately it's all mixed in with other stuff. Here is one place to start:

http://meditationstuff.wordpress.com/2013/07/16/dark-night-and-what-enlightenment-is-like/