Reexamining the effects of electrode location on measures of neural health in cochlear implant users.

The electrically evoked compound action potentials (ECAPs) amplitude-growth function (AGF) slope correlates with spiral ganglion neuron (SGN) density in the cochlear implanted cochlea. Electrode insertion angle and medial-lateral distance covary from base to apex; in some human ears, SGN survival varies from base to apex, making it difficult to parse out contributing factors to the ECAP AGF slope. Evoked compound action potentials were analyzed on each electrode and compared to post-operative computerized tomography scans.

Association of Aging and Cognition With Complex Speech Understanding in Cochlear-Implanted Adults: Use of a Modified National Institutes of Health (NIH) Toolbox Cognitive Assessment.

Importance: The association between cognitive function and outcomes in cochlear implant (CI) users is not completely understood, partly because some cognitive tests are confounded by auditory status. It is important to determine appropriate cognitive tests to use in a cohort of CI recipients.

Objective: To provide proof-of-concept for using an adapted version of the National Institutes of Health (NIH) Toolbox Cognition Battery in a cohort of patients with CIs and to explore how hearing in noise with a CI is affected by cognitive status using the adapted test.

Cochlear Health and Cochlear-implant Function.

The cochlear implant (CI) is widely considered to be one of the most innovative and successful neuroprosthetic treatments developed to date. Although outcomes vary, CIs are able to effectively improve hearing in nearly all recipients and can substantially improve speech understanding and quality of life for patients with significant hearing loss. A wealth of research has focused on underlying factors that contribute to success with a CI, and recent evidence suggests that the overall health of the cochlea could potentially play a larger role than previously recognized.

Components of impedance in a cochlear implant animal model with TGFβ1-accelerated fibrosis.

Outcomes of cochlear implantation are likely influenced by the biological state of the cochlea. Fibrosis is a pathological change frequently seen in implanted ears. The goal of this work was to investigate the relationship between fibrosis and impedance.

Estimating health of the implanted cochlea using psychophysical strength-duration functions and electrode configuration.

It is generally believed that the efficacy of cochlear implants is partly dependent on the condition of the stimulated neural population. Cochlear pathology is likely to affect the manner in which neurons respond to electrical stimulation, potentially resulting in differences in perception of electrical stimuli across cochlear implant recipients and across the electrode array in individual cochlear implant users. Several psychophysical and electrophysiological measures have been shown to predict cochlear health in animals and were used to assess conditions near individual stimulation sites in humans.