In this double-blind, crossover study of 8 boys with minimal brain
dysfunction, 20 mg of methylphenidate daily was significantly better than
160 mg of caffeine in controlling behavior, especially impulsivity and
hyperactivity, and methylphenidate alone was superior to decaffeinated
coffee and placebo. The tentative results of this study confirm the primary
position of sympathomimetics in the pharmacotherapy of minimal brain
dysfunction and, in addition, suggest the involvement of dopamine pathways
in this disorder. The authors urge further study of this hypothesis.