A1 Journal article (refereed)
CMC is more than a measure of corticospinal tract integrity in acute stroke patients (2021)

Aikio, R., Laaksonen, K., Sairanen, V., Parkkonen, E., Kujala, J., & Forss, N. (2021). CMC is more than a measure of corticospinal tract integrity in acute stroke patients. NeuroImage: Clinical, 32, Article 102818. https://doi.org/10.1016/j.nicl.2021.102818

JYU authors or editors

Publication details

All authors or editors: Aikio, R.; Laaksonen, K.; Sairanen, V.; Parkkonen, E.; Kujala, J.; Forss, N.

Journal or series: NeuroImage: Clinical

ISSN: 2213-1582

Publication year: 2021

Volume: 32

Article number: 102818

Publisher: Elsevier

Publication country: Netherlands

Publication language: English

DOI: https://doi.org/10.1016/j.nicl.2021.102818

Publication open access: Openly available

Publication channel open access: Open Access channel

Publication is parallel published (JYX): https://jyx.jyu.fi/handle/123456789/77909


In healthy subjects, motor cortex activity and electromyographic (EMG) signals from contracting contralateral muscle show coherence in the beta (15-30 Hz) range. Corticomuscular coherence (CMC) is considered a sign of functional coupling between muscle and brain. Based on prior studies, CMC is altered in stroke, but functional significance of this finding has remained unclear. Here, we examined CMC in acute stroke patients and correlated the results with clinical outcome measures and corticospinal tract (CST) integrity estimated with diffusion tensor imaging (DTI). During isometric contraction of the extensor carpi radialis muscle, EMG and magnetoencephalographic oscillatory signals were recorded from 29 patients with paresis of the upper extremity due to ischemic stroke and 22 control subjects. CMC amplitudes and peak frequencies at 13-30 Hz were compared between the two groups. In the patients, the peak frequency in both the affected and the unaffected hemisphere was significantly (p < 0.01) lower and the strength of CMC was significantly (p < 0.05) weaker in the affected hemisphere compared to the control subjects. The strength of CMC in the patients correlated with the level of tactile sensitivity and clinical test results of hand function. In contrast, no correlation between measures of CST integrity and CMC was found. The results confirm the earlier findings that CMC is altered in acute stroke and demonstrate that CMC is bidirectional and not solely a measure of integrity of the efferent corticospinal tract.

Keywords: cerebral cortex; neuromuscular activity; motor functions; cerebral infarction; MEG

Free keywords: afferent input; corticomuscular coherence; corticospinal tract integrity; magnetoencephalography; motor cortex; stroke

Contributing organizations

Ministry reporting: Yes

Last updated on 2021-27-09 at 10:34