Functional imaging of auditory scene analysis

Abstract

Our auditory system is constantly faced with the task of decomposing the complex mixture of sound arriving at the ears into perceptually independent streams constituting accurate representations of individual sound sources. This decomposition, termed auditory scene analysis, is critical for both survival and communication, and is thought to underlie both speech and music perception. The neural underpinnings of auditory scene analysis have been studied utilizing invasive experiments with animal models as well as non-invasive (MEG, EEG, and fMRI) and invasive (intracranial EEG) studies conducted with human listeners. The present article reviews human neurophysiological research investigating the neural basis of auditory scene analysis, with emphasis on two classical paradigms termed streaming and informational masking. Other paradigms - such as the continuity illusion, mistuned harmonics, and multi-speaker environments - are briefly addressed thereafter. We conclude by discussing the emerging evidence for the role of auditory cortex in remapping incoming acoustic signals into a perceptual representation of auditory streams, which are then available for selective attention and further conscious processing. This article is part of a Special Issue entitled Human Auditory Neuroimaging.

Keywords: ARN; BOLD; EEG; ISI; ITD; MEG; ROI; SSR; STG; awareness related negativity; blood oxygenation level dependent; electroencephalography; fMRI; frequency difference; functional magnetic resonance imaging; inter-aural time difference; inter-stimulus interval; magnetoencephalography; region of interest; steady-state response; superior temporal gyrus; ΔF.