Where is 'where' in the human auditory cortex?

Robert J Zatorre; Marc Bouffard; Pierre Ahad; Pascal Belin

doi:10.1038/nn904

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Where is 'where' in the human auditory cortex?

Robert J Zatorre·Marc Bouffard·Pierre Ahad·Pascal Belin

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Abstract

We examine the functional characteristics of auditory cortical areas that are sensitive to spatial cues in the human brain, and determine whether they can be dissociated from parietal lobe mechanisms. Three positron emission tomography (PET) experiments were conducted using a speaker array permitting quasi free-field sound presentation within the scanner. Posterior auditory cortex responded to sounds that varied in their spatial distribution, but only when multiple complex stimuli were presented simultaneously, implicating this cortical system in disambiguation of overlapping auditory sources. We also found that the right inferior parietal cortex is specifically recruited in localization tasks, and that its activity predicts behavioral performance, consistent with its involvement in sensorimotor integration and spatial transformation. These findings clarify the functional roles of posterior auditory and parietal cortices, and help to reconcile competing models of auditory cortical organization.

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Acoustic Stimulation Adult Auditory Cortex Auditory Pathways Brain Mapping Functional Laterality Humans Male Models, Neurological Nerve Net Orientation Parietal Lobe Psychomotor Performance Sound Localization Space Perception Tomography, Emission-Computed Journal Article Research Support, Non-U.S. Gov't

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Robert J Zatorre, Marc Bouffard, Pierre Ahad, Pascal Belin. 2002. Where is 'where' in the human auditory cortex?. https://doi.org/10.1038/nn904

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