Rapid short-term reorganization in the language network
- Max Planck Institute for Human Cognitive and Brain Sciences Leipzig, Germany
- RWTH Aachen, Germany
- University of Leipzig, Germany
Abstract
The adaptive potential of the language network to compensate for lesions remains elusive. We show that perturbation of a semantic region in the healthy brain induced suppression of activity in a large semantic network and upregulation of neighbouring phonological areas. After perturbation, the disrupted area increased its inhibitory influence on another semantic key node. The inhibitory influence predicted the individual delay in response speed, indicating that inhibition at remote nodes is functionally relevant. Individual disruption predicted the upregulation of semantic activity in phonological regions. In contrast, perturbation over a phonological region suppressed activity in the network and disrupted behaviour without inducing upregulation. The beneficial contribution of a neighbouring network might thus depend on the level of functional disruption and may be interpreted to reflect a differential compensatory potential of distinct language networks. These results might reveal generic mechanisms of plasticity in cognitive networks and inform models of language reorganization.
Article and author information
Author details
Funding
Deutsche Forschungsgemeinschaft (HA-6314-1-1)
- Gesa Hartwigsen
James F. MacDonnell Foundation
- Dorothee Saur
The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.
Reviewing Editor
- Heidi Johansen-Berg, University of Oxford, United Kingdom
Ethics
Human subjects: Written informed consent was obtained before the experiment.The study was performed according to the guidelines of the Declaration of Helsinki and approved by the local ethics committee (Medical Faculty at the University of Leipzig).
Version history
- Received: February 13, 2017
- Accepted: May 23, 2017
- Accepted Manuscript published: May 24, 2017 (version 1)
- Version of Record published: June 15, 2017 (version 2)
Copyright
© 2017, Hartwigsen et al.
This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.
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Rapid short-term reorganization in the language network
eLife 6:e25964.
https://doi.org/10.7554/eLife.25964
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