Effect of Audiometric Configuration on Binaural Temporal Fine Structure Sensitivity in Adults with Sensorineural Hearing Loss

Samira  Bagheri; Parisa Rasouli  Fard; Alireza Akbarzadeh  Baghban

doi:10.18502/avr.v35i2.21204

Samira Bagheri Department of Audiology, School of Rehabilitation, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Parisa Rasouli Fard Department of Audiology, School of Rehabilitation, Shahid Beheshti University of Medical Sciences, Tehran, Iran
Alireza Akbarzadeh Baghban Proteomics Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran

DOI: https://doi.org/10.18502/avr.v35i2.21204

Keywords: Temporal fine structure; sensorineural hearing loss; configuration; interaural phase difference

Abstract

Background and Aim: Temporal Fine Structure (TFS) cues are crucial for pitchperception, sound localization, and speech understanding in noise. Hearing loss can impairTFS sensitivity, but the role of audiogram configuration remains unclear. Therefore, thisstudy aimed to compare binaural TFS sensitivity in adults with Sensorineural Hearing Loss(SNHL) having different audiogram configurations.

Methods: This comparative cross-sectional study included 47 adults (32 with slopingaudiograms, 15 with rising/flat audiograms) aged 18–50 with bilateral mild to moderateSNHL (26–55 dB HL). All participants had normal outer and middle ear status, were right-handed, and had no cognitive impairment. TFS sensitivity was measured using the TFS-Low Frequency (TFS-LF) test at 250, 500, and 750 Hz, and the TFS-Adaptive Frequency(TFS-AF) test at Interaural Phase Differences (IPDs) of 45° and 135°.

Results: For the TFS-LF test, average thresholds were lower in the sloping group at allfrequencies, but the difference between the two groups was not significant (p>0.05). For theTFS-AF test, thresholds at IPD 135° were significantly higher than at IPD 45° (p<0.001),but the difference between the two groups was not significant. Significant correlations wereobserved between the TFS-LF and the TFS-AF thresholds (r=–0.783, p<0.001).

Conclusion: There is no significant difference in TFS sensitivity between adults withsloping and rising/flat audiograms. Absolute hearing thresholds at various frequencies donot solely influence TFS sensitivity; factors such as cochlear health, neural timing, andindividual variability may also affect the outcome