Multiple sclerosis: Left advantage for auditory laterality in dichotic tests of central auditory processing and relationship of psychoacoustic tests with the Multiple Sclerosis Disability Scale-EDSS.

Objective: To evaluate the central auditory processing disorders in patients with multiple sclerosis, emphasizing auditory laterality by applying psychoacoustic tests and to identify their relationship with the Multiple Sclerosis Disability Scale (EDSS) functions.

Method: Depression scales (HADS), EDSS, and 9 psychoacoustic tests to study CAPD were applied to 26 individuals with multiple sclerosis and 26 controls. Correlation tests were performed between the EDSS and psychoacoustic tests.

Results: Seven out of 9 psychoacoustic tests were significantly different (P<.05); right or left (14/19 explorations) with respect to control. In dichotic digits there was a left-ear advantage compared to the usual predominance of RDD. There was significant correlation in five psychoacoustic tests and the specific functions of EDSS.

Conclusion: The left-ear advantage detected and interpreted as an expression of deficient influences of the corpus callosum and attention in multiple sclerosis should be investigated. There was a correlation between psychoacoustic tests and specific EDSS functions.