Why the timing deficit hypothesis does not explain reading disability in adults

Abstract

It has been proposed that the phonological coredeficit that is linked to reading failure hasas its underlying cause a deficit in temporalprocessing. In a multivariate investigationdesigned to examine the temporal processingdeficit hypothesis, thirty reading-disabled(RD) adults, thirty-two normally achievingadults and thirty-one normally achievingchildren (reading-level controls) wereadministered a comprehensive battery thatincluded a wide range of timing tasks, inaddition to reading and phonological measures. Although adults with RD displayed overallperformance that was below that of normallyachieving adults on most of the timing tasks,their performance was not differentiallyinfluenced by rate of stimulus presentation. Although the RD adults displayed the typicalpattern of impaired phonological awareness andpseudoword reading relative to reading-levelmatched children, the reading-disabled adultsoutperformed the children on the timing tasks. Finally, with the exception of continuousnaming, the timing tasks shared little variancewith phonological sensitivity and contributedlittle unique variance to word reading. Although these findings undermine the timingdeficit hypothesis, they do provide evidencefor the involvement of naming deficits inreading disability.