Agreement Between Evoked Potentials and Behavioral Thresholds Using LS-Chirp and 1 kHz Tone Burst in Normal-Hearing...

Area of Science:

• Audiology
• Neuroscience
• Hearing Science

Background:

• Auditory evoked potentials (AEPs), including auditory brainstem response (ABR) and cortical auditory evoked potential (CAEP), are crucial for estimating hearing thresholds in non-responsive individuals.
• The relationship between brainstem/cortical activity and perceptual hearing thresholds, influenced by stimulus characteristics, requires further clarification.

Purpose of the Study:

• To investigate the agreement between AEPs (ABR and CAEP) and behavioral hearing thresholds.
• To determine how different stimulus types and presentation rates impact this agreement.

Main Methods:

• Two experiments were conducted on adult participants (n=8 and n=12 ears).
• Experiment 1 used LS CE-Chirp stimuli at 33.3 stimuli/second.
• Experiment 2 used 1 kHz tone bursts at varying rates (33.3 and 1.0 stimuli/second) and standard pure tone audiometry, with thresholds determined via the Hughson-Westlake method.

Main Results:

• For LS CE-Chirp stimuli at 33.3 stimuli/second, ABR showed better agreement with behavioral thresholds than CAEP (p < 0.05).
• For 1 kHz tone bursts at 1.0 stimuli/second, CAEP demonstrated better agreement than ABR (p < 0.05).
• At 33.3 stimuli/second with 1 kHz tone bursts, no significant difference in agreement was found between ABR and CAEP (p > 0.05). Both AEP types agreed comparably with clinical audiometry.

Conclusions:

• Stimulus type and presentation rate significantly influence auditory evoked potential threshold estimation.
• Slower presentation rates enhance agreement between cortical activity and behavioral thresholds, whereas faster rates favor brainstem activity agreement.
• These findings suggest context-dependent measurement strategies for identifying auditory dysfunction, warranting further validation in larger studies.