Noise levels required to mask stimuli used in auditory brainstem response testing

Area of Science:

• Audiology
• Neuroscience
• Hearing Science

Background:

• Auditory Brainstem Response (ABR) testing is essential for evaluating auditory pathway function.
• Effective masking is required to prevent non-test ear stimulation and ensure accurate ABR results.
• Understanding optimal noise levels is critical for reliable ABR interpretation.

Purpose of the Study:

• To determine the necessary noise levels for effectively masking auditory brainstem response (ABR) stimuli.
• To establish the upper limit of the relative masking level (RLM) for ABR testing.
• To provide a recommended value for noise calculation to prevent cross-hearing.

Main Methods:

• Behavioral measurement of relative masking level (RLM) in twenty normally-hearing volunteers.
• Use of ipsilaterally presented unfiltered noise during ABR stimuli.
• Calibration of stimuli in dBnHL to ISO 389-6 (2007) and noise measurement in dBSPL.

Main Results:

• The upper limit for RLM was found to be typically 30 dB above the stimulus level.
• This finding was consistent across normally-hearing participants.
• The study quantified the relationship between stimulus and noise levels for effective masking.

Conclusions:

• A relative masking level (RLM) of 30 dB above the stimulus level is recommended for ABR testing.
• This value aids in preventing auditory cross-hearing during ABR assessments.
• The findings contribute to standardized and accurate ABR test protocols.