caa a22 4500 606203362 CHVBK 20210128100957.0 cr unu---uuuuu 210128e20150301xx s 000 0 eng 10.1007/s00429-013-0702-8 doi (NATIONALLICENCE)springer-10.1007/s00429-013-0702-8 Motor cortex excitability and connectivity in chronic stroke: a multimodal model of functional reorganization [Elektronische Daten] [Lukas Volz, Anna-Sophia Sarfeld, Svenja Diekhoff, Anne Rehme, Eva-Maria Pool, Simon Eickhoff, Gereon Fink, Christian Grefkes] Cerebral ischemia triggers a cascade of cellular processes, which induce neuroprotection, inflammation, apoptosis and regeneration. At the neural network level, lesions concomitantly induce cerebral plasticity. Yet, many stroke survivors are left with a permanent motor deficit, and only little is known about the neurobiological factors that determine functional outcome after stroke. Transcranial magnetic stimulation (TMS) and magnetic resonance imaging (MRI) are non-invasive approaches that allow insights into the functional (re-) organization of the cortical motor system. We here combined neuronavigated TMS, MRI and analyses of connectivity to investigate to which degree recovery of hand function depends on corticospinal tract (CST) damage and biomarkers of cerebral plasticity like cortical excitability and motor network effective connectivity. As expected, individual motor performance of 12 stroke patients with persistent motor deficits was found to depend upon the degree of CST damage but also motor cortex excitability and interhemispheric connectivity. In addition, the data revealed a strong correlation between reduced ipsilesional motor cortex excitability and reduced interhemispheric inhibition in severely impaired patients. Interindividual differences in ipsilesional motor cortex excitability were stronger related to the motor deficit than abnormal interhemispheric connectivity or CST damage. Multivariate linear regression analysis combining the three factors accounted for more than 80% of the variance in functional impairment. The inter-relation of cortical excitability and reduced interhemispheric inhibition provides direct multi-modal evidence for the disinhibition theory of the contralesional hemisphere following stroke. Finally, our data reveal a key mechanism (i.e., the excitability-related reduction in interhemispheric inhibition) accounting for the rehabilitative potential of novel therapeutic approaches which aim at modulating cortical excitability in stroke patients. Springer-Verlag Berlin Heidelberg, 2014 Stroke nationallicence Cortical excitability nationallicence Functional reorganization nationallicence TMS nationallicence DCM nationallicence AH : Affected hand nationallicence AMT : Active motor threshold nationallicence ARAT : Action research arm test nationallicence CST : Corticospinal tract nationallicence DCM : Dynamic causal modeling nationallicence DTI : Diffusion tensor imaging nationallicence EMG : Electromyography nationallicence EPI : Echo planar imaging nationallicence FDI : First dorsal interosseus muscle nationallicence FDR : False discovery rate nationallicence fMRI : Functional magnetic resonance imaging nationallicence FWE : Family-wise error nationallicence FWHM : Full width at half maximum nationallicence GLM : General linear model nationallicence IHI : Interhemispheric inhibition nationallicence JTT : Jebsen-Taylor hand function test nationallicence M1 : Primary motor cortex nationallicence MEP : Motor evoked potential nationallicence MNI : Montreal Neurological Institute nationallicence MP-RAGE : Magnetization-prepared rapid acquisition gradient echo nationallicence MRI : Magnetic resonance imaging nationallicence mRS : Modified Rankin Scale nationallicence MSO : Maximum stimulator output nationallicence NIHSS : National Institutes of Health Stroke Scale nationallicence ROI : Region of interest nationallicence rTMS : Repetitive transcranial magnetic stimulation nationallicence SD : Standard deviation nationallicence SMA : Supplementary motor area nationallicence SPM : Statistical parametric mapping nationallicence tDCS : Transcranial direct current stimulation nationallicence TMS : Transcranial magnetic stimulation nationallicence UH : Unaffected hand nationallicence V1 : Primary visual cortex nationallicence vPMC : Ventral premotor cortex nationallicence Volz Lukas Neuromodulation and Neurorehabilitation, Max Planck Institute for Neurological Research, Gleueler Str. 50, 50931, Cologne, Germany aut Sarfeld Anna-Sophia Neuromodulation and Neurorehabilitation, Max Planck Institute for Neurological Research, Gleueler Str. 50, 50931, Cologne, Germany aut Diekhoff Svenja Neuromodulation and Neurorehabilitation, Max Planck Institute for Neurological Research, Gleueler Str. 50, 50931, Cologne, Germany aut Rehme Anne Neuromodulation and Neurorehabilitation, Max Planck Institute for Neurological Research, Gleueler Str. 50, 50931, Cologne, Germany aut Pool Eva-Maria Neuromodulation and Neurorehabilitation, Max Planck Institute for Neurological Research, Gleueler Str. 50, 50931, Cologne, Germany aut Eickhoff Simon Institute of Neuroscience and Medicine (INM-1, INM-3), Juelich Research Centre, Jülich, Germany aut Fink Gereon Department of Neurology, University of Cologne, Cologne, Germany aut Grefkes Christian Neuromodulation and Neurorehabilitation, Max Planck Institute for Neurological Research, Gleueler Str. 50, 50931, Cologne, Germany aut Brain Structure and Function Springer Berlin Heidelberg 220/2(2015-03-01), 1093-1107 1863-2653 220:2<1093 2015 220 429 https://doi.org/10.1007/s00429-013-0702-8 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s00429-013-0702-8 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Volz Lukas Neuromodulation and Neurorehabilitation, Max Planck Institute for Neurological Research, Gleueler Str. 50, 50931, Cologne, Germany aut NATIONALLICENCE 700 1- Sarfeld Anna-Sophia Neuromodulation and Neurorehabilitation, Max Planck Institute for Neurological Research, Gleueler Str. 50, 50931, Cologne, Germany aut NATIONALLICENCE 700 1- Diekhoff Svenja Neuromodulation and Neurorehabilitation, Max Planck Institute for Neurological Research, Gleueler Str. 50, 50931, Cologne, Germany aut NATIONALLICENCE 700 1- Rehme Anne Neuromodulation and Neurorehabilitation, Max Planck Institute for Neurological Research, Gleueler Str. 50, 50931, Cologne, Germany aut NATIONALLICENCE 700 1- Pool Eva-Maria Neuromodulation and Neurorehabilitation, Max Planck Institute for Neurological Research, Gleueler Str. 50, 50931, Cologne, Germany aut NATIONALLICENCE 700 1- Eickhoff Simon Institute of Neuroscience and Medicine (INM-1, INM-3), Juelich Research Centre, Jülich, Germany aut NATIONALLICENCE 700 1- Fink Gereon Department of Neurology, University of Cologne, Cologne, Germany aut NATIONALLICENCE 700 1- Grefkes Christian Neuromodulation and Neurorehabilitation, Max Planck Institute for Neurological Research, Gleueler Str. 50, 50931, Cologne, Germany aut NATIONALLICENCE 773 0- Brain Structure and Function Springer Berlin Heidelberg 220/2(2015-03-01), 1093-1107 1863-2653 220:2<1093 2015 220 429