Speech Categorization Consistency Predicts Language and Reading Abilities in School-Age Children: Implications for Language and Reading Disorders

Speech perception is fundamental to language and reading abilities. While these skills are correlated, most studies examining the role of speech perception on outcomes do not test both concurrently. Moreover, traditional forced-choice tasks have limitations in accurately indexing these relationships. This study used a visual analog scaling task—a continuous measure of speech categorization—to examine speech categorization alongside conventional language and reading assessments in a large sample of children, including those with language and/or reading disabilities. Children with poorer language/reading exhibited greater trial-to-trial categorization inconsistency, but no differences in the slope of the mean function. Group analyses further linked differences in categorization consistency to language/reading disabilities, with reading being linked particularly to vowels. Critically, categorization inconsistency uniquely predicted language/reading, even when controlling for the mediating effect of phonological processing. These findings suggest that the consistency of perceptual processes may be more important than the quality of the representations.