Frontotemporal activation differs between perception of simulated cochlear implant speech and speech in background noise: An image-based fNIRS study

• DOI: 10.1016/j.neuroimage.2021.118385
• Publication Date: 2021-07-10T07:13:36Z
• Authors: Jessica Defenderfer; Samuel Forbes; Sobanawartiny Wij...; Mark Hedrick; Patrick Plyler; Aaron T. Buss
• Keywords: Intelligibility (philosophy); Inferior frontal gyrus; Superior temporal gyrus

In this study we used functional near-infrared spectroscopy (fNIRS) to investigate neural responses in normal-hearing adults as a function of speech recognition accuracy, intelligibility the stimulus, and manner which is distorted. Participants listened sentences reported aloud what they heard. Speech quality was distorted artificially by vocoding (simulated cochlear implant speech) or naturally adding background noise. Each type distortion included high low-intelligibility conditions. Sentences quiet were baseline comparison. fNIRS data analyzed using newly developed image reconstruction approach. First, elevated cortical middle temporal gyrus (MTG) frontal (MFG) associated with during Second, activation MTG vocoded low intelligibility, whereas MFG activity largely driven noise, suggesting that response varies type. Lastly, an accuracy effect demonstrated significantly higher correct perception relative incorrect speech. These results suggest (i.e., untrained listeners stimuli) do not exploit same attentional mechanisms cortex resolve degraded may instead rely on segmental phonetic analyses lobe discriminate