THE CONCEPT of minimal brain dysfunction (MBD) was developed to account for a variety of obscure behavioral abnormalities often considered purely functional in nature.1-4 In a recent review of the subject Pincus and Glaser2 describe the motor, perceptual, and behavioral characteristics that comprise the MBD syndrome. They state that MBD is a "behavioral diagnosis." The children afflicted show "inappropriate activity," "disordered attention span," "poorly controlled behavior," "impulsiveness with destructive elements," "hyperkinesis," "outbursts of aggression, temper tantrums, sexual displays." There may be motor, perceptual, reading, and writing impairment, as well as poor ability at copying complex Gestalten.5-7 There is often a history of delayed developmental milestones as well as organic cerebral trauma due to complications of pregnancy, traumatic birth, head trauma, or intracerebral infection after birth. Abnormal behavior such as violent aggressiveness or lack of attention at school may thus be seen as due, in part, to organic