. >> tom and i were discussing earlier one example of this, helen mayberg's work. so she's doing imaging of people who are depressed. and depression as we discussed here involves the whole nearal circuit in which the-- is an important structure. and she created people with two types of therapy. a form of psycho therapy called cognitive behavior therapy. and the other group got antidepressants. and she found these two populations separated out depending upon the level of activity in the anteriorance letter that is remarkable insight to show you that you can predict based on brain image wag kinds of they were would be better for you. >> and -- >> spectacular. >> and she then went on to use deep brain stimulation. >> in a different region of the brain than what would you stimulate for park inson's disease an you can make the same argument that if you really understood the circuitry of depression that you could make the same kinds of advances that we believe you make with parkinson's disease with a better understanding and manipulation of the circuitry. >> that really