Categorization of common sounds by cochlear implanted and normal hearing adults

Area of Science:

• Auditory Perception
• Psychoacoustics
• Human-Computer Interaction

Background:

• Auditory categorization groups acoustic events by shared perceptual dimensions.
• Cochlear implant (CI) use impacts both high-level cognitive categorization and low-level acoustic processing.
• Understanding CI user auditory perception is crucial for improving device efficacy.

Purpose of the Study:

• To compare auditory categorization strategies between CI users and normal hearing listeners (NHL).
• To explore acoustic signal characteristics influencing sound categorization in CI users.
• To assess the extent of auditory discrimination difficulties in CI users.

Main Methods:

• A Free-Sorting Task was administered to 16 experienced CI users and 20 NHL.
• Participants sorted 16 common sounds across environmental, musical, and vocal categories.
• Multiple Correspondence Analysis (MCA) and Hierarchical Clustering based on Principal Components (HCPC) were employed for analysis.

Main Results:

• CI users demonstrated categorization strategies comparable to NHL, successfully discriminating between sound types.
• CI users exhibited greater variability and less inter-participant agreement in their categorization.
• Acoustic features like average pitch salience and autocorrelation peak significantly influenced sound perception and categorization.

Conclusions:

• CI users can broadly categorize sounds, suggesting fewer difficulties than previously assumed.
• Individual sound perception and fine-grained discrimination remain challenging for CI users.
• Acoustic signal properties play a key role in auditory categorization for both CI users and NHL.