Alternative Conceptualizations of Dyslexia: Evidence in Support of a Verbal-Deficit Hypothesis

Abstract

The history of our knowledge about specific reading disability—dyslexia—is checkered with different hypotheses and theories. In this overview of the literature Frank Vellutino critically examines the foci of four prevalent explanations for reading failure in children: visual perception, intersensory integration, temporal–order perception, and verbal functioning. Applying findings from his own laboratory investigations and other selected research to each of the four hypotheses,Vellutino argues that the verbal-deficit hypothesis offers the most convincing explanation. Through the use of direct and indirect evidence Vellutino demonstrates the relationship between reading problems and dysfunction in the semantic, syntactic,or phonological aspects of language. Finally, Vellutino pursues the implications of his position and asserts that the linguistic problems of some poor readers necessitate an emphasis on the internal structure of words in learning to read.