Yes, they do in fact exist, and based on how much you want to be studied, or submit your body to, you will get paid more......I looked into it here in Austin,Tx while in college, but after seeing all the release forms you have to sign basically signing over all your "rights to sue them in case anything goes wrong" I decided against it.........But my buddy did make some good $$$$ doing it...........One time he made $2k for enduring 20 panic attacks over a 48 period.........