Related Experiment Video
Updated: Oct 9, 2025
09:10
Performing Intracochlear Electrocochleography During Cochlear Implantation
Published on: March 8, 2022
4.6K
Intra-Cochlear Current Spread Correlates with Speech Perception in Experienced Adult Cochlear Implant Users
Charles-Alexandre Joly1,2,3, Pierre Reynard1,2,3, Ruben Hermann2,4,5
1Institut de l'Audition, Institut Pasteur, Université de Paris, INSERM, 75012 Paris, France.
Journal of Clinical Medicine
|December 24, 2021
Summary
Broader intra-cochlear current spread (ICCS) in cochlear implants (CI) negatively impacts speech understanding. Higher ICCS, measured by exponential spread coefficient (ESC), correlated with reduced speech intelligibility (I40) and higher speech reception thresholds (SRT50) in experienced users.
Area of Science:
- Audiology
- Biomedical Engineering
- Neuroscience
Background:
- Cochlear implant (CI) channel interactions are influenced by intra-cochlear current spread (ICCS).
- Understanding the relationship between ICCS and speech perception is crucial for optimizing CI performance.
Purpose of the Study:
- To investigate the correlation between ICCS and speech intelligibility in experienced CI users.
- To quantify ICCS using an individual exponential spread coefficient (ESC).
Main Methods:
- Voltage matrices from impedance measurements were used to compute ESC.
- Speech audiometry assessed intelligibility at 40 dB SPL (I40) and 50% speech reception threshold (SRT50).
- Correlations between ESC, I40, and SRT50 were analyzed in 36 adult CI users.
Main Results:
- A moderate negative correlation was found between ESC and I40 (r = -0.557, p = 0.009) in subjects with all active electrodes.
- A moderate positive correlation was observed between ESC and SRT50 (r = 0.569, p = 0.007) in the same subgroup.
- Increased ICCS was associated with poorer speech perception outcomes.
Conclusions:
- Broader ICCS negatively affects speech perception in CI users.
- Characterizing current spread near CI electrodes is essential for understanding CI stimulation and auditory perception.
Related Concept Videos
01:15Auditory Pathway
6.0K
Auditory pathways constitute the complex neural circuits responsible for transmitting and interpreting auditory information from the peripheral auditory system to the brain. Sound waves are initially captured by the outer ear, funneled through the ear canal, and reach the tympanic membrane (eardrum). These vibrations are transmitted via the middle ear's ossicles to the inner ear's cochlea.
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking...
When viewed cross-sectionally, the cochlea reveals the scala vestibuli and scala tympani flanking...
6.0K
01:17Auditory Perception
653
The auditory system is essential for sound perception, utilizing various critical structures. When sound waves enter the outer ear, they travel through the ear canal and cause the eardrum to vibrate. These vibrations are then transmitted to the middle ear, where three tiny bones – the malleus, incus, and stapes – amplify the sound. This amplification is crucial, as it ensures that the sound vibrations are strong enough to be conveyed to the inner ear. These vibrations then reach the...
653
01:13The Cochlea
46.9K
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.
46.9K
01:01Perception of Sound Waves
4.8K
The human ear is not equally sensitive to all frequencies in the audible range. It may perceive sound waves with the same pressure but different frequencies as having different loudness. Moreover, the perception of sound waves depends on the health of an individual's ears, which decays with age. The health of one's ears may also be affected by regular exposure to loud noises.
The pitch of a sound depends on the frequency and the pressure amplitude of the source. Two sounds of the same...
The pitch of a sound depends on the frequency and the pressure amplitude of the source. Two sounds of the same...
4.8K
01:31Hearing
53.7K
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.
53.7K
01:22Hair Cells
41.9K
Hair cells are the sensory receptors of the auditory system—they transduce mechanical sound waves into electrical energy that the nervous system can understand. Hair cells are located in the organ of Corti within the cochlea of the inner ear, between the basilar and tectorial membranes. The actual sensory receptors are called inner hair cells. The outer hair cells serve other functions, such as sound amplification in the cochlea, and are not discussed in detail here.
41.9K