Development and evaluation of the LiSN & learn auditory training software for deficit-specific remediation of binaural processing deficits in children: Preliminary findings

摘要

Background: The LiSN & Learn auditory training software was developed specifically to improve binaural processing skills in children with suspected central auditory processing disorder who were diagnosed as having a spatial processing disorder (SPD). SPD is defined here as a condition whereby individuals are deficient in their ability to use binaural cues to selectively attend to sounds arriving from one direction while simultaneously suppressing sounds arriving from another. As a result, children with SPD have difficulty understanding speech in noisy environments, such as in the classroom. Purpose: To develop and evaluate the LiSN & Learn auditory training software for children diagnosed with the Listening in Spatialized Noise - Sentences Test (LiSN-S) as having an SPD. The LiSN-S is an adaptive speech-in-noise test designed to differentially diagnose spatial and pitch-processing deficits in children with suspected central auditory processing disorder. Study Sample: Participants were nine children (aged between 6 yr, 9 mo, and 11 yr, 4 mo) who performed outside normal limits on the LiSN-S. Research Design: In a pre-post study of treatment outcomes, participants trained on the LiSN & Learn for 15 min per day for 12 weeks. Participants acted as their own control. Participants were assessed on the LiSN-S, as well as tests of attention and memory and a self-report questionnaire of listening ability. Performance on all tasks was reassessed after 3 mo where no further training occurred. Intervention: The LiSN & Learn produces a three-dimensional auditory environment under headphones on the user's home computer. The child's task was to identify a word from a target sentence presented in background noise. A weighted up-down adaptive procedure was used to adjust the signal level of the target based on the participant's response. Results: On average, speech reception thresholds on the LiSN & Learn improved by 10 dB over the course of training. As hypothesized, there were significant improvements in posttraining performance on the LiSN-S conditions where the target and distracter stimuli are spatially separated and which specifically evaluate binaural processing ability (p ranging from .003 to .0001, η 2 ranging from 0.694 to 0.873). In contrast, there was no improvement on the LiSN-S control conditions where the target and distracter stimuli emanate from the same direction (p ranging from .07 to .86, η 2 ranging from 0.362 to 0.004). Significant improvements were found posttraining on measures of memory, on one measure of attention, and on self-reported ratings of listening ability. There were no significant differences between post- and 3 mo posttraining scores on any of the assessment tools. Conclusions: The initial LiSN & Learn study has shown that children as young as 6 yr of age are able to complete the training (although some coaxing was needed in a minority of cases). Both parents and children have reported benefits from the training, and feedback from the trial has resulted in extra features being added to the software. In order to further evaluate the efficacy of LiSN & Learn to remediate binaural processing deficits in children a clinical trial is currently under way utilizing a randomized blinded control group design.