Language Development, Aphasia, and Dyslexia

Abstract

Probably the most compelling argument in favor of professional educators’ including neuropsychological knowledge in the understanding and treatment of children with learning problems is the close relationship between brain structure and function and the development of language. As Lenneberg (1967) has shown, the rules of language are biologically determined, because “all behavior, in general, is an integral part of an animal’s constitution.” It is related to structure and function, one being the expression of the other. Psychologists for many years have been interested in this dynamic interaction. “If a behavior sequence matures through regular stages irrespective of intervening practice, the behavior is said to develop through maturation and not through learning” (Hilgard, 1948). Put more simply, some forms of behavior result just because the animal grows older. Maturation must always precede learning, for all learning, and particularly for this discussion, verbal learning, is biologically dependent. By adopting the view that language is an aspect of a human’s biological development, “we may regard the language capacity virtually as we would a physical organ of the body, and can investigate the principles of its organization, functioning, and development in the individual and the species” (Chomsky, 1978).

It is known that the study of the function of separate parts of the brain began with observation of cases of speech pathology.

A.R. Luria (1964)

... there are major and fundamental differences between rules of language and rules of games. The former are biologically determined; the latter are arbitrary.

Eric H. Lenneberg (1967)

The concept (of aphasia) always has entailed both physiological and behavioral facets; this is one reason for its being difficult.

Helmer R. Myklebust (1971b)