Efficacy of Auditory Spatial Training with Real-Life Environmental Noise on Speech-in-Noise Intelligibility of Children with Hearing Loss

Purpose: This study aimed to determine whether auditory spatial training with real-life environmental noise would improve the speech-in-noise intelligibility of hearing-impaired children. Methods: Thirteen children with hearing loss participated in this study. We conducted an 8-week in-laboratory auditory spatial training. During the training, the target sentence and pre-recorded real-life environmental noise were spatially separated by 90°, and uncertainty about the location of the target and noise was given. To evaluate the efficacy of the training, sentence recognition with fluctuating and non-fluctuating noises was measured in a free sound-field condition, where the speech and noise sources were spatially separated and also co-located. The pre-training tests of sentence-in-noise recognition were performed twice with an interval of 6 weeks. The sentence-in-noise recognition test was also measured right after the 8-week training (post-training test) as well as 1 month after the completion of the training (retention test). In addition to the objective tests, the parents completed a subjective questionnaire on auditory behavior in everyday life before and after training. Results: There were no significant differences between the results of the two pre-training tests. The auditory spatial training significantly enhanced sentence-in-noise recognition in both spatially separated and co-located conditions at all signal-to-noise ratios, and the training efficacy was maintained until 1 month after the completion of the training. The parental subjective responses also showed positive changes after the training. Conclusion: An 8-week auditory spatial training could effectively enhance the speech-in-noise intelligibility of hearing-impaired children in spatialized as well as non-spatialized conditions.