It's quiet possible that the patents in the study who responded favorably have a form of ADHD and that playing Starcraft 2 gives their minds the mental stimulation they've been lacking. By giving these people Bupropion you're basically replacing the mental stimulation of Starcraft with the dopamine-induced stimulation of medication which basically allows them to be able to better focus on things other than video games. Ultimately it may prove that they are dependent on video games much like many of us are dependent on psychoactive drugs for our own well being.