Corticomuscular coherence in the acute and subacute phase after stroke. Issue 11 (November 2017)

• Record Type: Journal Article
• Authors: Larsen, Lisbeth Hoejkjaer; Zibrandtsen, Ivan Chrilles; Wienecke, Troels; Kjaer, Troels Wesenberg; Christensen, Mark Schram; Nielsen, Jens Bo; Langberg, Henning
• Is Part Of: Clinical neurophysiology. Volume 128:Issue 11(2017:Nov.)
• Page Start: 2217
• Page End: 2226
• Publication Date: 2017-11
• Subjects: ADP adductor pollicis -- APB abductor pollicis brevis -- CMC corticomuscular coherence -- CST corticospinal tract -- EEG electroencephalographic -- EMG electromyographic -- FDI first dorsal interosseous -- IMC intermuscular coherence -- M1 primary motor cortex -- MVC maximal voluntary contraction; Ischemic stroke -- Subacute phase -- Hemiparesis -- Motor recovery -- Corticomuscular coherence -- Intermuscular coherence; Neurophysiology -- Periodicals; Electroencephalography -- Periodicals; Electromyography -- Periodicals; Neurology -- Periodicals; 612.8
• DOI: 10.1016/j.clinph.2017.08.033
• Languages: English
• ISSNs: 1388-2457

Abstract

Highlights: Corticomuscular coherence (CMC) and intermuscular coherence (IMC) were reduced in acute and subacute stroke compared to healthy controls. CMC was localized above the contralateral sensorimotor cortex in both patients and controls. Improvement of hand motor performance did not require changes in CMC or IMC. Abstract: Objective: Stroke is one of the leading causes of physical disability due to damage of the motor cortex or the corticospinal tract. In the present study we set out to investigate the role of adaptations in the corticospinal pathway for motor recovery during the subacute phase after stroke. Methods: We examined 19 patients with clinically diagnosed stroke and 18 controls. The patients had unilateral mild to moderate weakness of the hand. Each patient attended two sessions at approximately 3 days (acute) and 38 days post stroke (subacute). Task-related changes in the communication between motor cortex and muscles were evaluated from coupling in the frequency domain between EEG and EMG during movement of the paretic hand. Results: Corticomuscular coherence (CMC) and intermuscular coherence (IMC) were reduced in patients as compared to controls. Paretic hand motor performance improved within 4–6 weeks after stroke, but no change was observed in CMC or IMC. Conclusions: CMC and IMC were reduced in patients in the early phase after stroke. However, changes in coherence do not appear to be an efficient marker for early recovery of hand function following stroke. Significance: This is the first study to demonstrate sustained reduced coherence in acute and subacute stroke.