Model-based hearing-enhancement strategies for cochlear synaptopathy pathologies

Area of Science:

• Auditory Neuroscience
• Signal Processing
• Audiology

Background:

• Ageing and noise exposure cause sensorineural hearing loss, damaging inner ear structures and the auditory nerve (AN).
• Cochlear synaptopathy (CS), or synaptic damage to the AN, is suspected in individuals with hearing difficulties but normal audiograms.
• Current hearing aid algorithms do not address the deficits caused by CS.

Purpose of the Study:

• To present and evaluate novel auditory signal-processing strategies aimed at restoring AN coding in listeners with CS.
• To assess the effectiveness of these algorithms in improving physiological and behavioral markers of CS.

Main Methods:

• Development and evaluation of advanced auditory signal-processing strategies.
• Testing algorithms on subjects with and without suspected age-related CS.
• Measurement of envelope-following responses, amplitude-modulation sensitivity, and speech-in-noise intelligibility.

Main Results:

• Algorithms consistently enhanced envelope-following responses and perceptual amplitude-modulation sensitivity in all listeners.
• Speech-in-noise intelligibility showed modest improvements, particularly in young normal-hearing participants (up to 8.3%).
• The strategies effectively improved temporal-envelope processing for both CS and non-CS listeners.

Conclusions:

• The developed hearing-enhancement strategies optimize auditory nerve fiber stimulation.
• These algorithms improve auditory processing for individuals with and without suspected cochlear synaptopathy.
• Rapid execution allows integration into current hearing aids and hearables without altering sound amplification.