Estimating Nonorganic Hearing Thresholds Using Binaural Auditory Stimuli.

Area of Science:

• Audiology
• Hearing Science
• Psychoacoustics

Background:

• Minimum contralateral interference levels (MCILs) are crucial for assessing true hearing thresholds in individuals with unilateral nonorganic hearing loss.
• Understanding the accuracy of MCILs in predicting true hearing thresholds is essential for effective clinical diagnosis.

Purpose of the Study:

• To determine MCILs in adults with normal hearing who feigned unilateral hearing loss.
• To examine the correspondence between MCILs and true hearing thresholds to quantify the accuracy of this estimation procedure.

Main Methods:

• Sixteen adults with normal hearing participated in the study.
• Participants were instructed to simulate a unilateral hearing loss at 1.0, 2.0, and 4.0 kHz.
• MCILs were measured, and participants made lateralization judgments with varying interaural intensity differences.

Main Results:

• The 90% confidence intervals indicated that MCILs were typically close to true thresholds or up to 17-19 dB poorer.
• The proximity of MCIL to the true hearing threshold was found to be dependent on the individual's response criterion.
• Response bias significantly influences MCIL values and their relationship to true hearing thresholds.

Conclusions:

• Clinicians cannot ascertain a client's response bias, necessitating the use of confidence intervals for threshold prediction.
• A 90% confidence interval should be employed to estimate the expected true threshold range.
• Based on this approach, clinicians can infer that the true threshold is at or up to 19 dB better than the determined MCIL.