Auditory Experience, Speech Sound Production Growth, and Early Literacy in Children Who Are Hard of Hearing

Children who are hard of hearing (CHH) are at risk for literacy difficulties. Speech sound production is related to literacy skills in typically hearing children. Speech sound production abilities can also be markedly weak in CHH due to inconsistent access to the speech signal. We longitudinally examined relations between auditory experience, speech sound production abilities, and literacy (i.e., nonword reading and spelling in second grade) in CHH. Participants included 166 CHH. All participants used hearing aids (HAs). Auditory experience is a weighted measure of the number of hours of daily HA use and the amount of audibility with and without their HAs. Children's speech sound production was tested 2-3 times between the ages of 3 and 9 years. At age 5 years and again in second grade, children were tested on a battery of language and literacy measures. Auditory experience was significantly correlated with speech sound production abilities, but age at HA fitting was not. Speech sound production abilities at age 5 years did not predict nonword reading in second grade but did predict spelling skills in second grade. Our results support the importance of auditory experience and speech sound production for later literacy abilities. Specifically, we found that speech sound production abilities and print knowledge at age 5 years are related to second grade spelling outcomes. Interestingly, we found that morphological knowledge at age 5 years was more predictive of decoding in second grade than was speech sound production. Although there are multiple factors that contribute to literacy success, our results underscore the unique contributions of speech sound production abilities in CHH.