ABSTRACT
This chapter traces the evolution of the minimal brain dysfunction (MBD) concept from three separate areas: learning difficulties, hyperkinetic-impulsive behavior, and neurological “soft signs”. The presence of common etiological factors, such as perinatal complications leading to minimal brain damage, is a necessary criterion if hyperkinetic-impulsive behavior, learning difficulties, and neurological “soft signs” are manifestations of a specific syndrome. The hypothesis of a “continuum of reproductive casualty” of Pasamanick and his colleagues was most influential in the evolution of the MBD concept. A final issue relating to the existence of an MBD syndrome is the response of affected children to stimulant drugs. The importance of the psychopharmacological data to the MBD concept centers, of course, on whether the response to the drugs is unique to these children. The symptoms of another possible MBD subgroup could be the result of fetal maldevelopment.
