Perceptual Binding and Temporal Coherence in the Auditory COrtex

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Dutta, Kelsey Jayne
Shamma, Shihab A
Auditory streaming and perceptual binding are functions performed by the auditory brain rapidly and without conscious effort. They are fundamental for how we analyze and understand the sound environment including the perception of speech and ability to attend to one speaker while ignoring background noise. Recent work has suggested that temporal coherence of frequency components is a key cue which causes the brain to group channels and into a unified auditory stream. Coherent frequency inputs will lead to coherent neuronal firing, and we hypothesize that such neurons will demonstrate reciprocal enhancement of firing rate or suppression of responses to incoherent channels. This dissertation examines neuronal activity from the auditory cortex of ferrets in order to better understand the role of temporal coherence in formation of auditory streams. One experiment examines the role of temporal coherence in a selective attention task paradigm, and the other uses a stochastic figure-ground stimulus to examine neural correlates of a perceptual “pop-out” during passive listening. A third project develops a biophysically plausible model for a pitch-processing neuron in the early auditory system.