Loudness balance between electric and acoustic stimulation.

Area of Science:

• Neuroscience
• Audiology
• Biomedical Engineering

Background:

• Binaural loudness balance is crucial for auditory perception.
• Auditory brainstem implants (ABIs) offer hearing restoration for specific patient groups.
• Understanding loudness perception in ABI users is key for optimizing device function.

Purpose of the Study:

• To investigate the relationship between electric and acoustic loudness perception in ABI users.
• To develop a predictive model for loudness growth in electric stimulation.
• To explore implications for speech processor design in ABIs.

Main Methods:

• Binaural loudness balance measurements were performed in ABI listeners with residual acoustic hearing.
• A linear model was established relating acoustic decibels (dB) to electric microamps (µA).
• An exponential loudness growth model was derived from the linear relationship.

Main Results:

• A linear relationship was observed between acoustic hearing levels and electric stimulation levels required for loudness balance.
• The proposed exponential model accurately describes loudness growth in electric stimulation.
• The model predicts that loudness growth is determined by threshold and uncomfortable loudness levels.

Conclusions:

• The findings support an exponential model for electric loudness growth in ABI users.
• This model simplifies the determination of loudness functions based on key electric parameters.
• The results have direct implications for refining speech processor strategies in auditory brainstem implantation.