The Purpose of Synchronicity: Neural Oscillations Align Excitability with Linguistic Informativeness
In auditory neuroscience, there is emerging consensus that neural oscillations phase-synchronize with frequency-isomorphous acoustic and linguistic rhythms in speech. Yet, the tracking of certain rhythms is not language comprehension—which requires the understanding of the syntactic and semantic information that speech actually symbolizes. I will present here evidence that oscillatory synchronicity may indeed facilitate linguistic information processing. First, I will show that delta-band oscillatory phase can drive sentence interpretations that contradict acoustic cues. Second, I will show that oscillatory synchronicity aligns neural excitability (as indexed by delta-band oscillatory phase and ERPs) with linguistic informativeness (as quantified by information-theoretic metrics)—facilitating language comprehension (as measured through a high-level linguistic task). I will argue that phase-synchronization during speech processing is not a self-contained mechanism to ensure high-fidelity rhythm tracking; instead, phase-synchronization serves to optimally align information extraction capacities with linguistic information.