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, η2 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, η2 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.
Key Words auditory stream segregation - central auditory processing disorder - spatial processing
disorder
