Title: Cortical processing of spectrally degraded speech: A human intracranial electrophysiology perspective

Speaker: Kirill V. Nourski, MD, PhD

Despite progress in cochlear implant (CI) technology, there is considerable variability in outcomes, attributed in part to the function of central auditory pathways. Spectrally degraded sounds presented to normal-hearing listeners can be used to approximate cortical sound processing by CI users. Intracranial electroencephalography (iEEG) work in neurosurgical epilepsy patients reveals differential cortical responses to clear and spectrally degraded (noise-vocoded) speech stimuli. Better behavioral identification of vocoded phonemes is associated with greater activation of the cortical dorsal auditory stream. Differential responses to clear and vocoded sentences are observed both in early and late portions of the sentence, suggesting sustained, rather than transient, responses. Clear-preferred responses are likely driven by spectral complexity and intelligibility. Vocoded-preferred responses may reflect increased processing demands associated with challenging listening conditions. Identifying regions involved in the processing of degraded speech has potential clinical utility and present candidate targets for neuromodulation-based CI rehabilitation strategies.

Zoom link for online seminars (used throughout the semester):

https://uiowa.zoom.us/j/97359327852?pwd=0HDya18oxt4Yg8FiBr4WAn0F5jnzMw.1

Meeting ID: 973 5932 7852 Passcode: 219629