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An Automated System for Sound Localization Testing in Hearing-Impaired Listeners
Published on: March 13, 2026
Cochlear implant patients' localization using interaural level differences exceeds that of untrained normal hearing
Justin M Aronoff1, Daniel J Freed, Laurel M Fisher
1Communication and Neuroscience Division, House Research Institute, 2100 West 3rd Street, Los Angeles, California 90057, USA. jaronoff@hei.org
The Journal of the Acoustical Society of America
|May 8, 2012
Summary
Bilateral cochlear implant users struggle with sound localization compared to normal hearing individuals. However, this study found their ability to use interaural level differences for localization exceeds that of untrained normal hearing listeners.
Area of Science:
- Auditory Neuroscience
- Audiology
- Bioacoustics
Background:
- Bilateral cochlear implant (CI) users exhibit poorer sound localization than normal hearing listeners.
- Deficits in interaural time difference (ITD) sensitivity contribute to this, but the role of interaural level difference (ILD) sensitivity is less understood.
Purpose of the Study:
- To investigate the contribution of interaural level differences (ILDs) to the sound localization deficits in bilateral cochlear implant (CI) users.
- To compare the ILD-based localization abilities of bilateral CI users with those of normal hearing listeners.
Main Methods:
- Localization was assessed in bilateral CI users and normal hearing listeners.
- Head-related transfer functions were used to manipulate interaural time and level cues.
Main Results:
- Bilateral CI users demonstrated a greater ability to localize sounds using interaural level differences (ILDs) compared to untrained normal hearing listeners.
- This finding suggests that ILD processing may not be the primary limiting factor in bilateral CI users' overall localization performance.
Conclusions:
- Bilateral CI users' capacity for utilizing interaural level differences for sound localization is surprisingly robust.
- Further research should explore how ITD deficits interact with preserved ILD processing in CI users to impact spatial hearing.
Related Concept Videos
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01:21Perceiving Loudness, Pitch, and Location
The human brain perceives pitch through two primary mechanisms reflected in place theory and frequency theory. Each mechanism describes how sound waves are interpreted as specific pitches by the brain, offering insights into the intricate processes of auditory perception.
Place theory, or place coding, suggests that different pitches are heard because various sound waves activate specific locations along the cochlea's basilar membrane. The brain determines the pitch of a sound by identifying...
Place theory, or place coding, suggests that different pitches are heard because various sound waves activate specific locations along the cochlea's basilar membrane. The brain determines the pitch of a sound by identifying...