Decoding spatial versus non-spatial processing in auditory working memory

  • Objective: Research on visual working memory has shown that individual stimulus features are processed in both specialized sensory regions and higher cortical areas. Much less evidence exists for auditory working memory. Here, a main distinction has been proposed between the processing of spatial and non-spatial sound features. Our aim was to examine feature-specific activation patterns in auditory working memory. Methods: We collected fMRI data while 28 healthy adults performed an auditory delayed match-to-sample task. Stimuli were abstract sounds characterized by both spatial and non-spatial information, i.e., interaural time delay and central frequency, respectively. In separate recording blocks, subjects had to memorize either the spatial or non-spatial feature, which had to be compared with a probe sound presented after a short delay. We performed both univariate and multivariate comparisons between spatial and non-spatial task blocks. Results: Processing of spatial sound features elicited a higher activity in a small cluster in the superior parietal lobe than did sound pattern processing, whereas there was no significant activation difference for the opposite contrast. The multivariate analysis was applied using a whole-brain searchlight approach to identify feature-selective processing. The task-relevant auditory feature could be decoded from multiple brain regions including the auditory cortex, posterior temporal cortex, middle occipital gyrus, and extended parietal and frontal regions. Conclusion: In summary, the lack of large univariate activation differences between spatial and non-spatial processing could be attributable to the identical stimulation in both tasks. In contrast, the whole-brain multivariate analysis identified feature-specific activation patterns in widespread cortical regions. This suggests that areas beyond the auditory dorsal and ventral streams contribute to working memory processing of auditory stimulus features.
Author:Mira Erhart, Stefan CzoschkeORCiDGND, Cora FischerORCiDGND, Christoph BledowskiORCiDGND, Jochen KaiserORCiDGND
Parent Title (English):Frontiers in neuroscience
Publisher:Frontiers Research Foundation
Place of publication:Lausanne
Document Type:Article
Date of Publication (online):2021/02/19
Date of first Publication:2021/02/19
Publishing Institution:Universitätsbibliothek Johann Christian Senckenberg
Release Date:2021/05/17
Tag:searchlight analysis
auditory; functional magnetic resonance imaging; location; multivoxel pattern analysis; pitch; working memory
Issue:art. 637877
Page Number:10
First Page:1
Last Page:10
Copyright © 2021 Erhart, Czoschke, Fischer, Bledowski and Kaiser. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.
Dewey Decimal Classification:6 Technik, Medizin, angewandte Wissenschaften / 61 Medizin und Gesundheit / 610 Medizin und Gesundheit
Licence (German):License LogoCreative Commons - Namensnennung 4.0