I was quoting from this Atlantic article, which easily could have misinterpreted the science (I admit this is common): http://www.theatlantic.com/health/archive/2014/04/treating-c...

Here's the original paper: http://www.psych.uncc.edu/pagoolka/seminar/jofpain2009.pdf

Most of the confidence in my post comes from personal observation. I don't claim that should be convincing to you--but it is convincing to me.