Purpose: Atypical difficulty perceiving speech in noise is one of the behavioral symptoms frequently reported for auditory processing disorder (APD). However, currently there is no consensus regarding the underlying mechanisms for this deficit. Motivated by a view that this is a cumulative result of acoustic-phonetic processing failures, the present study examined the effect of increasing linguistic complexity on speech perception in noise by children who failed audiologic screening for APD. Methods: Listeners were 84 7-to-12 yearold English-speaking children with normal hearing. Nine children failed audiologic APD screening and were referred for further testing (children with referral); 75 were typically-developing peers. Using an adaptive procedure, signal-to-noise ratios required for 70%-correct recognition of words and sentences (SNR70) were obtained for each listener to quantify additional deficit due to sentence context when listening to speech in noise. Results: Despite reported deficits in noise, and contrary to our prediction, no group difference in SNR70 was observed between children with referral and their typically-developing peers. Analysis for individual differences showed that SNR70 for only one child with referral was outside the bounds established for the typically-developing children. Conclusion: Our results did not reflect the reported atypically compromised speech perception in noise by children with referral when compared to their typicallydeveloping peers, implying that these difficulties stem neither from the deficit in acoustic-phonetic processing nor the deficit in the use of sentence context. The present results also suggest that speech perception in noise deficit in APD require more complex speech materials and/or acoustic environments.
MATERIALS AND METHODS