Question

9. Children (approximately 11 years old) with cochlear implants (CI) and children with typical hearing (TH) were asked to listen to speech with a background of noise under different conditions in a classroom setting. The different conditions were the number of sound-absorbing acoustic panels hung on the walls in the classroom. This affected the reverberation time (RT). With more panels, there was less reverberation (0.3s). With fewer panels, there was more reverberation (0.9s). The signal-to-noise ratio was measured in decibels (dBA). The higher the number, the speech was louder than the noise. The lower the number (<0) the noise was louder than the speech.

a. Did children with cochlear implants score higher on speech perception at higher signal-to-noise ratios than children with typical hearing? Give data in support of your answer. [2]

b. You are in charge of classroom design for a school with mixed CI and TH children. What do you recommend? Give reasons with data. [2]

Answer 1

a. Several studies have been reported about the compariosn between the cochlear implants(CI) and typical hearing (TH) individuals, where the signals to noise ratios (SNR) in varying decibels were used for the study (DOI: 10.1067/mhn.2002.123044, Shojaei et al., 2016, Dorman et al., 1998). Although majortity of these studies focused on adults, certain studies provides evidence that no correlation was found between age and speech perception at silence and also in different SNRs (Signal to noise ratio), whereas few suggest the reduced perception ability on elderly,s. Since the present analysis is on Children such reduction seems invalid.

A higher SNRs is a favourable condition where there is more speech than noise, hence both the groups can exhibit a better performance, because a better SNR ratio can result in same level of performance as normal individuas (Ching et al., 2018).