- Effect of methylphenidate on executive functioning in adults with attention-deficit/hyperactivity disorder: normalization of behavior but not related brain activity. Schweitzer, J.B., Lee, D.O., Hanford, R.B., Zink, C.F., Ely, T.D., Tagamets, M.A., Hoffman, J.M., Grafton, S.T., Kilts, C.D. Biol. Psychiatry (2004)