Loudness ratio production by cochlear implantees using the spectral maxima sound processor

Area of Science:

• Audiology
• Biomedical Engineering
• Neuroscience

Background:

• Cochlear implants (Mini System 22) aim to restore hearing by converting sound into electrical stimulation.
• Understanding loudness perception is crucial for optimizing cochlear implant function.
• Individual variability in loudness perception exists among implant users.

Purpose of the Study:

• To evaluate the loudness growth characteristics of Mini System 22 cochlear implant users.
• To compare these characteristics with normally hearing subjects.
• To assess the suitability of the sound processor's amplitude conversion function.

Main Methods:

• Employed the method of loudness ratio production.
• Measured loudness growth in five Mini System 22 users and five normally hearing subjects.
• Compared the decibel change required to halve or double perceived loudness.

Main Results:

• Normally hearing subjects required an average of 10.8 dB for loudness halving/doubling.
• Three cochlear implant users showed comparable results (average 8.83 dB).
• Two users exhibited significantly different loudness growth patterns.

Conclusions:

• Loudness perception varies among cochlear implant users.
• The sound processor's amplitude conversion function may not be suitable for all users.
• Limited input dynamic range of the sound processor might influence loudness perception in some individuals.