CHENFIT-AMP, a nonlinear fitting and amplification strategy for cochlear hearing loss

Area of Science:

• Audiology
• Bioacoustics
• Hearing Science

Background:

• Cochlear hearing loss requires advanced amplification strategies.
• Existing methods like NAL-NL2 and MCC have limitations in individualizing gain.
• Outer hair cell (OHC) and inner hair cell (IHC) loss necessitate distinct gain adjustments.

Purpose of the Study:

• To introduce CHENFIT-AMP, a novel nonlinear strategy for cochlear hearing loss.
• To compare CHENFIT-AMP's gain prescription and implementation with NAL-NL2 and MCC.
• To evaluate the audibility and preference of CHENFIT-AMP using speech stimuli.

Main Methods:

• CHENFIT-AMP combines fitting (gain prescription) and amplification (gain implementation).
• Gain prescription accounts for OHC and IHC loss, input level, and potential "dead regions."
• CHEN's loudness model estimates input level and cochlear gain for amplification.

Main Results:

• CHENFIT-AMP showed similar gain to NAL-NL2 for typical audiograms but offered more individualized gain for varied slopes.
• MCC with NAL-NL2 parameters did not fully implement the prescribed gain for noise inputs.
• Subjects preferred CHENFIT-AMP amplification, reporting a louder perception compared to MCC.

Conclusions:

• CHENFIT-AMP provides more individualized gain prescription than NAL-NL2.
• CHENFIT-AMP's amplification is preferred and perceived as louder than MCC.
• This strategy offers a promising advancement in hearing loss rehabilitation.