Dichotic Listening Deficit Associated With Solvent Exposure.

HYPOTHESIS: A significant left ear deficit can be observed in solvent-exposed individuals using the dichotic digit test.

BACKGROUND: 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.

METHODS: 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).

RESULTS: 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.

CONCLUSION: 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.