Both !
For Dr. John Sarno "unexplained" pain is a distraction provided by our brain in order to keep "incorrect", unbearable emotions hidden/buried in our subconscious.
For modern neuroscience pain (both unexplained or explained) is always a danger signal, a warning/protective message, an alarm in front of real or potential dangers coming not only from but our body ....but also from our life/mind !
For Sarno unconcious rage is the principal fuel for "unexplained" pain.
For neurosciente the main factor of pain is fear.
Both points of view are fully compatibly: distraction is a form of protection, and fear about our "enraged inner/residual child" is devastating.
Just my two cents!