Spoken language processing in noise by deaf and hard of hearing children: effects of speaking rate

While school-aged children who are deaf or hard of hearing (DHH) spend much of the day in classrooms or playgrounds, little is known about how aspects of these environments, such as fast speech and background noise, affect their ability to process sentences in real time. The current study compared processing of sentences in 16-talker babble noise spoken at a fast (6.1 syll./s) vs normal (4.5 syll./s) speaking rates in twenty-seven 8–13-year-old children with hearing in the normal range (NH) and 31 DHH children. Children were instructed to detect a target word in a sentence, and response time (RT) was taken as an outcome measure. Relationships between working memory capacity, vocabulary knowledge, and RT were also assessed, but not observed. Both groups of children were slower to process fast speech than normal-rate speech, with no evidence that DHH children were differentially affected by speaking rate compared to peers with NH. DHH children processed sentences in noise slower than their peers with NH across speaking rates. These results suggest that children's sentence processing can be disrupted when they encounter fast speech in a noisy environment, and that DHH children may be most at risk for spoken sentence processing delays in real-world listening environments.