Mismatch negativity in auditory neuropathy/auditory dys-synchrony

Abstract

Abstract Auditory neuropathy/auditory dys-synchrony (AN/AD) is a recently described hearing disorder that has unique pathologies and perceptual consequences. Difficulty in understanding speech is a consistently reported consequence of this type of hearing loss. These patients can detect speech sounds but cannot discriminate what they have heard. Objectives: This work was designed to investigate fine discrimination abilities in these patients and to assess the possibility of there being any abnormalities which might contribute to the difficulty in speech perception. Method: Subjects were classified into 2 groups: control group (GI) composed of 20 normal hearing subjects and the study group (GII) composed of 17 AN/AD patients. All cases were subjected to: full audiological history, otological examination, basic audiological evaluation, Mismatch Negativity (MMN) using tone stimuli in 4 paradigms. Results: MMN response was significantly delayed in AN/AD group when compared to control with some difference between tested frequencies. Conclusion: MMN provided an excellent tool for assessing fine discrimination in AN/AD patients.