The effects of auditory training on dichotic listening: a neurological case study

Background: Individuals with neurological impairment have been shown to have deficits in auditory processing abilities. One auditory processing ability shown to be affected is dichotic listening. To date, limited evidence exists demonstrating the effectiveness of dichotic listening intervention on dichotic listening in individuals with neurological impairment. The purpose of this study was to determine the effects of the dichotic listening training on dichotic listening abilities over multiple training periods in an individual with a long-standing and stable neurological history. Method: This study used a case study design. Over the course of 3 years, an individual with dichotic listening deficits following a left cerebral vascular accident underwent multiple auditory training periods using a dichotic listening training paradigm. Initial assessments indicated a bilateral deficit on the Dichotic Digits test with the right ear performing more poorly than the left ear and a right ear deficit on the Dichotic Rhyme test. Training sessions took place 2–3 times per week for a period of 4–11 weeks in the years 2012, 2013 and 2014. Pre- and post-training assessments of dichotic listening and hearing in noise ability were completed for each training period. Results: Results indicated improvements in the trained (right) ear on the Dichotic Digits test following each of the three training periods. Results also indicated stable performance in the right ear on the Dichotic Rhyme test and variable performance on the Words-in-Noise (WIN) test following each training session. Performance on the Dichotic Digits test decreased slightly between training periods; however, overall performance showed improvement over time. Conclusion: These results suggest improved binaural integration abilities as measured by the Dichotic Digits test following dichotic listening training in an individual with neurological impairment. However, the effects of the training did not transfer to tasks of binaural fusion (Dichotic Rhyme test) or hearing in noise (WIN test) tasks.