[Noise signal reduction in cochlear implant speech processors]

Area of Science:

• Audiology
• Biomedical Engineering
• Speech Processing

Background:

• Cochlear implant users experience communication difficulties in noise.
• Environmental noise impairs auditory-verbal communication for hearing aid and cochlear implant users.
• The mini-22 cochlear implant system features a Mini Speech Processor (MSP) with noise suppression.

Purpose of the Study:

• To evaluate the effectiveness of the MSP's noise suppression function in cochlear implant users.
• To compare speech understanding with and without noise suppression in quiet and noisy conditions.
• To assess the impact of the spectral peak (SPEAK) stimulation strategy on speech intelligibility.

Main Methods:

• 18 experienced postlingually-deafened adult cochlear implant users participated.
• Speech intelligibility was measured using computer-assisted units, including the Freiburg speech intelligibility test and a new sentence test.
• Paired observations were conducted in both quiet and noisy environments, comparing different MSP modes and the SPEAK strategy.

Main Results:

• Noise suppression significantly improved speech understanding in noise.
• Normal MSP mode was better in quiet conditions.
• The spectral peak (SPEAK) strategy resulted in a 40% average increase in intelligibility compared to MSP with noise suppression.
• Significant interindividual differences in benefit from noise suppression were observed.

Conclusions:

• The noise suppression function in the Mini Speech Processor (MSP) offers benefits for cochlear implant users in noisy environments.
• The spectral peak (SPEAK) stimulation strategy provides a significant advancement in speech understanding for cochlear implant users, especially in interfering noise.
• Individual results with noise suppression vary, with factors like S-position usage influencing outcomes.