The term learning disabilities, as a categorical entity, is attributed to Samuel Kirk (Kirk & Bateman, 1962), although there had been many earlier studies of academic underachievers. The history of neuropsychology, with its emphasis on brain damage or impairment as a basis for limiting higher-level abilities, made it reasonable to postulate a biological basis for learning disabilities. It must be recognized, however, that a host of factors (including genetic and maturational variables, auditory and/or visual impairments, differences in rates of development, conflicts in handedness and footedness, variations in cognitive style, deviant patterns of cerebral dominance, emotional and psychiatric problems, and, perhaps the most common cause, poor teaching) have been implicated. Aware of these many possible etiological influences, Spreen (1976) favored a ‘multiple cause — multiple outcome interaction model.’ Learning disabilities obviously represent a complex condition, and many factors can be contributory.

Rourke's research program

The first systematic program of investigation based on a modern neuropsychological approach was instituted by Rourke (1975). (See Spreen's related discussion of Rourke's work in Chapter 9, where the focus is on Rourke's theory rather than on his research methodology.) From the beginning, Rourke included subjects who were performing very poorly in one or more academic subjects, but excluded children with mental retardation, emotional disturbances, cultural deprivation, and defective hearing or vision as primary factors, despite poor academic progress.