Connection between video gaming & social anxiety?

Have any professionals found any connection between video gaming and social anxiety?  My son is 19 and spends every spare moment in high level gaming.  He does go to work (for a friend) but is gaming all of his free time.  He doesn't eat properly, because he won't leave the game.  It is interactive and he is speaking with other gamers.  He doesn't see his friends anymore.  He is nervous even joining the extended family for gatherings.  He is on prozac for social anxiety, but will not talk to a therapist/psychologist.  He thinks that he just has to deal with mind over matter - which isn't really working well.  He has been promising to sign up for on-line college classes for a year and has not followed-through.