Newman, Wroblewski, Hajick and Rubenstein (2012){{1}}[[1]]Newman, A, Wroblewski, M, Hajicek, J, and Rubenstein, A (2012) Measuring speech Recognition in Children with Cochlear Implants in a Virtual Classroom, J. Speech, Language, Hrng Res; 55, 532-540.[[1]]have published a very interesting article in the Journal of Speech and Hearing Research describing a study they conducted to try and assess how children with cochlear implants would hear in a noisy classroom. On some level we all know that classroom listening is difficult for children with hearing loss who use hearing aids or cochlear implants. We know that competing noise and reverberation both affect listening. However, testing in noise is not routinely performed on children (I have no idea why not – it should be, and I do it) and testing in reverberant conditions cannot be done in standard soundproof rooms.
Making a virtual classroom
Newman et al (2012) made a recording of speech in a typical reverberant classroom and used this material to test children with normal hearing and children with cochlear implants.
How do normal hearing kids perform?
In this study, children with normal hearing demonstrated a very slight drop in speech recognition when listening in the quiet but reverberant virtual classroom. Scores ranged from 97-100%. When noise was added to the reverberant conditions, children with normal hearing needed speech to be a little louder than the noise to hear well. Six-year-olds needed speech to be about 6 dB louder and it dropped slightly each year until 12 years when they required speech to be about 2 dB louder than the noise to understand 50% of the words.
How do kids with CI’s perform?
Kids with CI’s did well in quiet (93-100%), but they did performed poorly in a quiet but reverberant classroom, dropping to a mean of 76% with a range of 55% to 88%. As expected, children with cochlear implants had more difficulty when speech was added to the reverberant conditions. They required from 6 to 15 dB SNR to understand 50% of the words. The authors reported that the differences in scores did not seem to be related to age or to length of CI use.
What can we conclude?
While this study was performed on children with cochlear implants, results can be extrapolated to children with hearing aids. Since most children with hearing loss are now educated in mainstream settings, it is important to pay attention to classroom listening skills. A classroom can be a very difficult listening condition for any child with hearing loss. For kids to succeed it is essential that we make classroom listening as easy as possible. We need to monitor performance as well as we can, being sure we test in noise in the audiology suite and also test in reverberant classrooms. Children with hearing loss need assistance to make the signal acoustically accessible, which means that there is no child with hearing loss who does not need an FM system full time in any academic situation and in many non-academic situations. While FM’s cannot solve all problems, they can VERY significantly improve listening in noise and reverberant conditions.
