Related Experiment Video
Updated: Jul 18, 2026
04:32
Sound Source Localization Testing in Single-sided Deafness Following Bone Conduction Intervention
Published on: December 20, 2024
The occlusion effect in unilateral versus bilateral hearing aids
Charlotte Thunberg Jespersen1, Jennifer Groth, Jürgen Kiessling
1GN Resound as, Denmark. cjespersen@gnresound.dk
Journal of the American Academy of Audiology
|December 13, 2006
Summary
Open hearing aid vents reduce the occlusion effect, making bilateral hearing aid use more comfortable. This suggests open fittings can encourage more users to wear two hearing aids instead of one.
Area of Science:
- Audiology
- Hearing Science
- Biomedical Engineering
Background:
- Bilateral hearing aids offer benefits, yet many users opt for single aids.
- The occlusion effect, a sensation of "plugged ears," may deter bilateral hearing aid use.
Purpose of the Study:
- To quantify the subjective occlusion effect in unilateral versus bilateral hearing aid use.
- To evaluate the impact of various vent designs on the occlusion effect.
- To determine if open-fit hearing aids can mitigate the occlusion effect and promote bilateral use.
Main Methods:
- Ten experienced bilateral hearing aid users and ten normal-hearing individuals rated voice naturalness aloud.
- Subjective occlusion effect was measured in unilateral and bilateral conditions.
- Various earmold vent designs and a custom hearing aid were tested.
Main Results:
- Bilateral hearing aids significantly increased the subjective occlusion effect across most vent designs.
- Open vent designs and non-occluding eartips substantially reduced the occlusion effect.
- The occlusion effect was lower in both unilateral and bilateral conditions with more open vents.
Conclusions:
- The occlusion effect is a significant barrier to bilateral hearing aid adoption.
- Open-hearing-aid fittings effectively reduce the subjective occlusion effect.
- Implementing open-fit solutions can encourage greater use of bilateral hearing aids.
Related Concept Videos
01:13The Cochlea
The cochlea is a coiled structure in the inner ear that contains hair cells—the sensory receptors of the auditory system. Sound waves are transmitted to the cochlea by small bones attached to the eardrum called the ossicles, which vibrate the oval window that leads to the inner ear. This causes fluid in the chambers of the cochlea to move, vibrating the basilar membrane.
01:31Hearing
When we hear a sound, our nervous system is detecting sound waves—pressure waves of mechanical energy traveling through a medium. The frequency of the wave is perceived as pitch, while the amplitude is perceived as loudness.
01:28Lateralization
Brain lateralization refers to the division of mental processes and functions between the two hemispheres of the brain, a phenomenon that optimizes neural efficiency and underpins complex abilities in humans. This specialization allows each hemisphere to perform tasks where it has a comparative advantage, facilitating more refined cognitive capabilities across different domains.
01:11The Auditory Ossicles
The auditory ossicles of the middle ear transmit sounds from the air as vibrations to the fluid-filled cochlea. The auditory ossicles consist of two malleus (hammer) bones, two incus (anvil) bones, and two stapes (stirrups), one on each side. These bones develop during the fetal stage and are the ones to ossify first. They are fully mature at birth and do not grow afterward.
The aptly named stapes look very much like a stirrup. The three ossicles are unique to mammals, and each plays a role in...
The aptly named stapes look very much like a stirrup. The three ossicles are unique to mammals, and each plays a role in...