Rahimi, Setareh, Farahibozorg, Seyedeh Rezvan, Jackson, Rebecca et al. (1 more author) (2022) Task modulation of spatiotemporal dynamics in semantic brain networks:An EEG/MEG study. Neuroimage. 118768. ISSN 1053-8119
Abstract
How does brain activity in distributed semantic brain networks evolve over time, and how do these regions interact to retrieve the meaning of words? We compared spatiotemporal brain dynamics between visual lexical and semantic decision tasks (LD and SD), analysing whole-cortex evoked responses and spectral functional connectivity (coherence) in source-estimated electroencephalography and magnetoencephalography (EEG and MEG) recordings. Our evoked analysis revealed generally larger activation for SD compared to LD, starting in primary visual area (PVA) and angular gyrus (AG), followed by left posterior temporal cortex (PTC) and left anterior temporal lobe (ATL). The earliest activation effects in ATL were significantly left-lateralised. Our functional connectivity results showed significant connectivity between left and right ATL, PTC and right ATL in an early time window, as well as between left ATL and IFG in a later time window. The connectivity of AG was comparatively sparse. We quantified the limited spatial resolution of our source estimates via a leakage index for careful interpretation of our results. Our findings suggest that the different demands on semantic information retrieval in lexical and semantic decision tasks first modulate visual and attentional processes, then multimodal semantic information retrieval in the ATLs and finally control regions (PTC and IFG) in order to extract task-relevant semantic features for response selection. Whilst our evoked analysis suggests a dominance of left ATL for semantic processing, our functional connectivity analysis also revealed significant involvement of right ATL in the more demanding semantic task. Our findings demonstrate the complementarity of evoked and functional connectivity analysis, as well as the importance of dynamic information for both types of analyses.
Metadata
Item Type: | Article |
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Authors/Creators: |
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Copyright, Publisher and Additional Information: | Funding Information: This work was supported by intramural funding from the Medical Research Council UK ( MC_UU_00005/18 ), a British Academy Postdoctoral Fellowship awarded to R.L.J. (No. pf170068 ), and Cambridge University international scholarships awarded to S.R. and S.R.F. S.R.F. is supported by Wellcome Trust ( 215573/Z/19/Z , 203139/Z/16/Z ). For the purpose of open access, the author has applied a CC BY public copyright license to any Author Accepted Manuscript version arising from this submission. Publisher Copyright: © 2021 |
Keywords: | Controlled semantic cognition,Leakage,MEG,Semantic control,Semantic representation,Source estimation |
Dates: |
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Institution: | The University of York |
Academic Units: | The University of York > Faculty of Sciences (York) > Psychology (York) |
Depositing User: | Pure (York) |
Date Deposited: | 13 Jul 2022 10:00 |
Last Modified: | 16 Oct 2024 18:33 |
Published Version: | https://doi.org/10.1016/j.neuroimage.2021.118768 |
Status: | Published |
Refereed: | Yes |
Identification Number: | 10.1016/j.neuroimage.2021.118768 |
Related URLs: | |
Open Archives Initiative ID (OAI ID): | oai:eprints.whiterose.ac.uk:189052 |
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Description: Task modulation of spatiotemporal dynamics in semantic brain networks: An EEG/MEG study
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