Audiological Profile of Adult Persons with Auditory Neuropathy Spectrum Disorders

Abstract

Background and ObjectivesThe auditory profile of a large number of persons with late onset auditory neuropathy spectrum disorder (ANSD) is recently described in the Indian context. The purpose of study was 1) to profile data on routine audiological parameters, cortical evoked potentials, and temporal processing, 2) to analyze the benefit from hearing aids for persons with ANSD, and 3) to understand the association between benefit from hearing aids and auditory profile.Subjects and MethodsThirty-eight adults with late onset ANSD and a matched group of 40 normally hearing adults participated in the study. Basic audiological tests, recording of cortical evoked potentials, and temporal processing tests were carried out on both groups of participant while only persons with ANSD were fitted with hearing aid.ResultsSubjects in the two groups were significantly different on all the audiological parameters. ANSD group seemed to benefit from hearing aids variably. The mean amplitude of N2 was significantly different between normally-hearing participants and patients with ANSD.ConclusionsResidual temporal processing, particularly amplitude modulation detection seems to be associated with benefit from hearing aids in patients with ANSD.

Behavioural and Electrophysiological Correlates of Aided Performance in Individuals with Late Onset Auditory Neuropathy Spectrum Disorder: A Review

“…Yuvaraj and Mannarukrishnaiah [ 24 ] investigated aided improvement in speech identification in 38 individuals with late onset ANSD. Further, they estimated the relation between audiological findings (PTA, SIS, and temporal processing) and aided benefit.…”

“…However, the extent of aided improvement in majority of the clients is limited. Investigations by Mathai and Yathiraj [ 23 ] as well as Yuvaraj and Mannarukrishnaiah [ 24 ] showed aided improvement above 20%, whereas other studies have shown lesser aided improvement. Relatively higher aided improvement in a few participants was attributed to preserved neural synchrony.…”

Inner hair cell synapse density influences auditory processing

“…In humans with sensorineural hearing loss, longer gap detection thresholds correlate with poorer speech perception (45-47). Our results show that gap-detection is diminished with synaptopathy and improved with supranormal IHC synapse density, thus supporting the notion that noise- and age-induced synaptopathy (3, 11, 15) contribute to the deficits in auditory processing seen in humans.…”

“…Self-reporting studies indicate that 10% to 20% of adult humans with normal audiometric thresholds have hearing difficulties (56)(57)(58)(59). Furthermore, humans with sensorineural hearing loss, particularly in the high frequencies, have longer gap-detection thresholds that correlate with poorer speech perception (60)(61)(62)(63)(64). It has been proposed that cochlear synaptopathy could contribute to this highly prevalent auditory dysfunction (3,11,15).…”

Auditory Deficits in Patients With Mild and Moderate Obstructive Sleep Apnea Syndrome: A Speech Syllable Evoked Auditory Brainstem Response Study

“…The temporal measurements of click-ABR, such as the latencies of featured peaks I, III and V, and the interpeak periods I–V, I–III and III–V, were identified by the trained experts and measured in the SmartEP system. The data of speech-ABR were transferred to a Brainstem toolbox [14-16] on MATLAB platform (MathWorks, Natick, MA, USA) which is increasingly used in the customized analysis of ABR research [26] for further analysis. The automated peak-picking algorithm in the toolbox was used to detect all peaks objectively for a higher confidence.…”