@article{63351e4c6e14400894be5aa6ca03e330,
title = "Task-evoked metabolic demands of the posteromedial default mode network are shaped by dorsal attention and frontoparietal control networks",
abstract = "External tasks evoke characteristic fMRI BOLD signal deactivations in the default mode network (DMN). However, for the corresponding metabolic glucose demands both decreases and increases have been reported. To resolve this discrepancy, functional PET/MRI data from 50 healthy subjects performing Tetris were combined with previously published data sets of working memory, visual and motor stimulation. We show that the glucose metabolism of the posteromedial DMN is dependent on the metabolic demands of the correspondingly engaged task-positive networks. Specifically, the dorsal attention and frontoparietal network shape the glucose metabolism of the posteromedial DMN in opposing directions. While tasks that mainly require an external focus of attention lead to a consistent downregulation of both metabolism and the BOLD signal in the posteromedial DMN, cognitive control during working memory requires a metabolically expensive BOLD suppression. This indicates that two types of BOLD deactivations with different oxygen-to-glucose index may occur in this region. We further speculate that consistent downregulation of the two signals is mediated by decreased glutamate signaling, while divergence may be subject to active GABAergic inhibition. The results demonstrate that the DMN relates to cognitive processing in a flexible manner and does not always act as a cohesive task-negative network in isolation.",
keywords = "BOLD signal, deactivation, default mode network, functional PET, glucose metabolism, human, neuroscience",
author = "Godbersen, {Godber M.} and Sebastian Klug and Wolfgang Wadsak and Verena Pichler and Julia Raitanen and Anna Rieckmann and Lars Stiernman and Luca Cocchi and Michael Breakspear and Marcus Hacker and Rupert Lanzenberger and Andreas Hahn",
note = "Funding Information: Wolfgang Wadsak: declares to having received speaker honoraria from the GE Healthcare and research grants from Ipsen Pharma, Eckert-Ziegler AG, Scintomics, and ITG; and working as a part time employee of CBmed Ltd. (Center for Biomarker Research in Medicine, Graz, Austria). Marcus Hacker: received consulting fees and/or honoraria from Bayer Healthcare BMS, Eli Lilly, EZAG, GE Healthcare, Ipsen, ITM, Janssen, Roche, and Siemens Healthineers. Rupert Lanzenberger: received investigator-initiated research funding from Siemens Healthcare regarding clinical research using PET/ MRI. He is a shareholder of the start-up company BM Health GmbH since 2019. The other authors declare that no competing interests exist. Funding Information: We thank the graduated team members and the diploma students of the Neuroimaging Lab (NIL, head: R Lanzenberger) as well as the clinical colleagues from the Department of Psychiatry and Psychotherapy for clinical and/or administrative support. In detail, we would like to thank S Kasper, K Papageorgiou, P Michenthaler, T Vanicek, A Basaran, M Hienert, L Silberbauer, J Unterholzner and G Gryglewski for medical support, L Rischka and M B Reed for analysis support, V Ritter, K Einenkel and E Sittenberger for subject recruitment and A Jelicic for partly implementation of the task. We are further grateful to J V{\"o}lkle and A Pomberger for radioligand synthesis. The scientific project was performed with the support of the Medical Imaging Cluster of the Medical University of Vienna. This research was funded in whole, or in part, by the Austrian Science Fund (FWF) KLI 610, PI: A Hahn. 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. S Klug is supported by the MDPhD Excellence Program of the Medical University of Vienna. A Rieckmann and L Stiernman are supported by the European Research Council under the European Union{\textquoteright}s Horizon 2020 research and innovation program ERC-STG-716065 to A Rieckmann. L Cocchi is supported by the Australian NHMRC (GN2001283). Funding Information: This research was funded in whole, or in part, by the Austrian Science Fund (FWF) KLI 610, PI: A Hahn. 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. S Klug is supported by the MDPhD Excellence Program of the Medical University of Vienna. A Rieckmann and L Stiernman are supported by the European Research Council under the European Union{\textquoteright}s Horizon 2020 research and innovation program ERC-STG-716065 to A Rieckmann. L Cocchi is supported by the Australian NHMRC (GN2001283). Publisher Copyright: {\textcopyright} Godbersen et al.",
year = "2023",
month = may,
day = "25",
doi = "10.7554/eLife.84683",
language = "English",
volume = "12",
journal = "eLife",
issn = "2050-084X",
publisher = "ELIFE SCIENCES PUBLICATIONS LTD",
}