Mapping the functional pathways to speech intelligibility using neuroimaging techniques: A study of incremental speech perception

Abstract

Speech perception involves a complex feedforward/feedback process of decoding bottom-up auditory input while utilizing top-down cognitive/linguistic knowledge to map stored word forms onto incoming acoustic waves (Kinchla & Wolfe, 1979; Sloos & McKeown, 2015). Speech perception in the brain is believed to occur as a result of cortical spreading from the core of the auditory cortex (and peripheral areas), diffusing into non-speech-specific areas of the brain responsible for binding information and memory retrieval. The current study traces the functional pathways between regions associated with speech perception using a combination of fMRI and EEG imaging. Our principle aim is to determine how normal functional connectivity between language-processing areas differs from speech perception where speech ranges from unintelligible (e.g., English phonetic non-word sentences) to intelligible with spontaneous disruptions (code-switched utterances) up to fully intelligible speech. Testing disruption of speech inte...