Exploring objective measures of auditory temporal resolution using auditory brainstem responses (ABRs)

Abstract

Accurately assessing auditory temporal resolution, the ability to detect rapid changes in sound, is crucial for diagnosing and understanding supra-threshold hearing impairments. While traditional behavioural approaches (e.g., gap detection tasks) are effective, they rely on active participation, making them unsuitable for populations such as infants or individuals with cognitive or communicative challenges. This thesis investigates both subjective (behavioural) and objective (electrophysiological) measures of temporal resolution, aiming to develop an objective method using the Auditory Brainstem Response (ABR).
A pilot study evaluates multiple ABR paradigms, identifying the Two-Click (2C) and Temporal Notched Noise with Click (TNNC) paradigms as promising approaches for measuring temporal resolution thresholds. These paradigms are then further examined in a following full experiment using advanced statistical techniques (Hotelling’s T2, Fsp, and bootstrap resampling) to reduce observer bias in peak identification, improving diagnostic robustness. Both approaches provide promising estimates of temporal resolution at the group level; however, considerable individual variability presents a challenge. Test–retest validation reveals the TNNC paradigm as the more reliable method, with better consistency.
The TNNC paradigm is then separated into forward and backward masking conditions to further investigate the neuronal substrates of temporal resolution. While forward masking ABR findings support neural adaptation at the brainstem level, backward masking does not elicit comparable markers, suggesting involvement of higher-level auditory processing. Behavioural data reveal distinct threshold patterns compared to electrophysiological results, highlighting the multifaceted nature of temporal resolution and the importance of integrating objective and subjective measures.
By systematically examining behavioural and ABR outcomes with identical stimuli, this research demonstrates the feasibility of an ABR-based framework for populations unable to perform behavioural tasks. Although individual response variability currently limits immediate clinical application in single cases, these findings enhance our understanding of brainstem responses to rapid auditory temporal events at a group level. Further refinements and standardisation are needed to optimise its clinical use, but this work establishes a solid foundation for future investigation of temporal resolution in diverse patient populations.

More information

Identifiers

ORCID for Esma Akis: orcid.org/0000-0002-5680-0256

ORCID for David Simpson: orcid.org/0000-0001-9072-5088

Catalogue record

Export record