It's obviously the beginning of a research project. Take a drug - see what it does to 'normal' people with the testing platform you are using (in this case functional MRI), then try it on different clinical diagnoses. Remember, most medical diagnoses and especially psychiatric ones are not binary events - they lie on a continuum. We really don't know how to diagnose most patients with complex psychiatric problems. We typically give them several overlapping diagnoses that really don't explain the patient's problems and medicate them accordingly. I've always thought there should be a 'just plain nuts' category. It would be more objective and honest.
Treatment of psychiatric issues with medications is still in it's infancy and it's still akin to using hand grenades instead of scalpels. Studies like this one are trying to pin point areas of regulation and dysregulation with the eventual idea of finding more specific treatments.
Of course, that means more specific ways of controlling someone's mind. Which has its upsides. And it downsides.