The relation between categorical perception of speech stimuli and reading skills in children

Abstract

Children ages 7 to 14 years listened to seven tokens, /ga/ to /ka/ synthesized in equal steps from 0 to 60 ms along the voice onset time (VOT) continuum, played in continuous rhythm. All possible changes (21) between the seven tokens were presented seven times at random intervals, maintaining the rhythm. Children were asked to press a button as soon as they detected a change. Maps of the seven tokens, constructed from multidimensional scaling of reaction times, indicated two salient dimensions: one phonological and the other acoustic/phonetic. Better reading, spelling, and phonological processing skills were associated with greater relative weighting of the phonological as compared to the acoustic dimension, suggesting that children with reading difficulty and associated deficits may underweight the phonological and/or overweight the acoustic information in speech signals. This task required no training and only momentary memory of the tokens. That an analysis of a simple task coincides with more complex reading tests suggests a low-level deficit (or shift in listening strategy). Compared to control children, children with reading disabilities may pay more attention to subtle details in these signals and less attention to the global pattern or attribute. [Supported by NIH Grant 1 RO1 HD35938 to JIB.]