Evaluating cortical responses to speech in children: A functional near-infrared spectroscopy (fNIRS) study.

Lawrence, Rachael J, Wiggins, Ian M, Hodgson, Jessica and Hartley, Douglas E (2020) Evaluating cortical responses to speech in children: A functional near-infrared spectroscopy (fNIRS) study. Hearing Research . ISSN 0378-5955

Full content URL: https://doi.org/10.1016/j.heares.2020.108155

Documents
Evaluating cortical responses to speech in children: A functional near-infrared spectroscopy (fNIRS) study.
Authors' Accepted Manuscript
[img] PDF
1-s2.0-S0378595520304263-main.pdf - Whole Document
Restricted to Repository staff only until 15 December 2021.
Available under License Creative Commons Attribution-NonCommercial-NoDerivatives 4.0 International.

1MB
Item Type:Article
Item Status:Live Archive

Abstract

Functional neuroimaging of speech processing has both research and clinical potential. This work is facilitating an ever-increasing understanding of the complex neural mechanisms involved in the processing of speech. Neural correlates of speech understanding also have potential clinical value, especially for infants and children, in whom behavioural assessments can be unreliable. Such measures would not only benefit normally hearing children experiencing speech and language delay, but also hearing impaired children with and without hearing devices. In the current study, we examined cortical correlates of speech intelligibility in normally hearing paediatric listeners. Cortical responses were measured using functional near-infrared spectroscopy (fNIRS), a non-invasive neuroimaging technique that is fully compatible with hearing devices, including cochlear implants. In nineteen normally hearing children (aged 6 – 13 years) we measured activity in temporal and frontal cortex bilaterally whilst participants listened to both clear- and noise-vocoded sentences targeting four levels of speech intelligibility. Cortical activation in superior temporal and inferior frontal cortex was generally stronger in the left hemisphere than in the right. Activation in left superior temporal cortex grew monotonically with increasing speech intelligibility. In the same region, we identified a trend towards greater activation on correctly vs. incorrectly perceived trials, suggesting a possible sensitivity to speech intelligibility per se, beyond sensitivity to changing acoustic properties across stimulation conditions. Outside superior temporal cortex, we identified other regions in which fNIRS responses varied with speech intelligibility. For example, channels overlying posterior middle temporal regions in the right hemisphere exhibited relative deactivation during sentence processing (compared to a silent baseline condition), with the amplitude of that deactivation being greater in more difficult listening conditions. This finding may represent sensitivity to components of the default mode network in lateral temporal regions, and hence effortful listening in normally hearing paediatric listeners. Our results indicate that fNIRS has the potential to provide an objective marker of speech intelligibility in normally hearing children. Should these results be found to apply to individuals experiencing language delay or to those listening through a hearing device, such as a cochlear implant, fNIRS may form the basis of a clinically useful measure of speech understanding.

Keywords:Speech processing, Auditory cortex, fNIRS, Children
Subjects:C Biological Sciences > C850 Cognitive Psychology
B Subjects allied to Medicine > B620 Speech Science
C Biological Sciences > C820 Developmental Psychology
Divisions:College of Science > Lincoln Medical School
Related URLs:
ID Code:43420
Deposited On:18 Dec 2020 11:38

Repository Staff Only: item control page