Landry Simon P, Fuente Adrian
*School of Speech Pathology and Audiology, Faculty of Medicine, University of Montreal †Research Centre of the Montreal Geriatric University Institute, Québec, Canada.
Otol Neurotol. 2017 Jul;38(6):e68-e74. doi: 10.1097/MAO.0000000000001445.
A significant left ear deficit can be observed in solvent-exposed individuals using the dichotic digit test.
Solvents are ubiquitous in global industrial processes. Due to their lipophilic nature, solvents can adversely affect large white matter tracks such as the corpus callosum. Previous investigations reveal that long-term workplace exposure to solvents is also deleterious to various auditory processes. Investigations in exposed populations suggest a decreased performance for dichotic listening.
In this present study, we examined the lateralization of a dichotic digit test score for 49 solvent-exposed individuals along with 49 age- and sex-matched controls. We evaluated group differences between test scores and the right ear advantage using a laterality index (LI).
Individual ear results suggest that long-term workplace solvent exposure is associated with a significantly lower dichotic listening score for the left ear. A binaural compound score analysis using a laterality index supports this left-ear deficit.
These results provide an insight on the effects of solvent exposure on dichotic listening abilities. Further research should investigate the importance of using dichotic listening tasks to screen for solvent-induced auditory dysfunction in exposed individuals.