Prefrontal cortex supports speech perception in listeners with cochlear implants
- Washington University in St. Louis, United States
- University of Utah, United States
Abstract
Cochlear implants are neuroprosthetic devices that can restore hearing in people with severe to profound hearing loss by electrically stimulating the auditory nerve. Because of physical limitations on the precision of this stimulation, the acoustic information delivered by a cochlear implant does not convey the same level of acoustic detail as that conveyed by normal hearing. As a result, speech understanding in listeners with cochlear implants is typically poorer and more effortful than in listeners with normal hearing. The brain networks supporting speech understanding in listeners with cochlear implants are not well understood, partly due to difficulties obtaining functional neuroimaging data in this population. In the current study, we assessed the brain regions supporting spoken word understanding in adult listeners with right unilateral cochlear implants (n=20) and matched controls (n=18) using high-density diffuse optical tomography (HD-DOT), a quiet and non-invasive imaging modality with spatial resolution comparable to that of functional MRI. We found that while listening to spoken words in quiet, listeners with cochlear implants showed greater activity in the left prefrontal cortex than listeners with normal hearing, specifically in a region engaged in a separate spatial working memory task. These results suggest that listeners with cochlear implants require greater cognitive processing during speech understanding than listeners with normal hearing, supported by compensatory recruitment of the left prefrontal cortex.
Data availability
Stimuli, data, and analysis scripts are available from https://osf.io/nkb5v/.
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Prefrontal cortex supports speech perception in listeners with cochlear implantsOSF, https://osf.io/nkb5v/.
Article and author information
Author details
Jonathan Erik Peelle
Funding
National Institutes of Health (R21DC015884)
- Jonathan Erik Peelle
National Institutes of Health (R21DC016086)
- Jonathan Erik Peelle
National Institutes of Health (K01MH103594)
- Adam T Eggebrecht
National Institutes of Health (R21MH109775)
- Adam T Eggebrecht
National Institutes of Health (R01NS090874)
- Joseph P Culver
National Institutes of Health (R01NS109487)
- Joseph P Culver
National Institutes of Health (R21DC015884)
- Joseph P Culver
National Institutes of Health (R21DC016086)
- Joseph P Culver
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Ethics
Human subjects: All subjects were native speakers of English with no self-reported history of neurological or psychiatric disorders. All aspects of these studies were approved by the Human Research Protection Office (HRPO) of the Washington University School of Medicine. Subjects were recruited from the Washington University campus and the surrounding community (IRB 201101896, IRB 201709126). All subjects gave informed consent and were compensated for their participation in accordance with institutional and national guidelines.
Copyright
© 2022, Sherafati et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Prefrontal cortex supports speech perception in listeners with cochlear implants
eLife 11:e75323.
https://doi.org/10.7554/eLife.75323
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