Spastic co-contraction is directly associated with alterations in movement kinematics and upper limb motor function.
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Altered cortical oscillatory activity may reflect an important mechanism underlying spastic co-contraction.
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Cortical beta oscillations may be a potential marker for motor recovery in stroke subjects.
Abstract
Objective
Spastic co-contraction is a motor-disabling form of muscle overactivity occurring after a stroke, contributing to a limitation in active movement and a certain level of motor impairment. The cortical mechanisms underlying spastic co-contraction remain to be more fully elucidated, the present study aimed to investigate the role of the cortical beta oscillations in spastic co-contraction after a stroke.
Method
We recruited fifteen post-stroke participants and nine healthy controls. The participants were asked to perform active elbow extensions. In the study, multimodal analysis was performed to combine the evaluation of three-dimensional elbow kinematics, the elbow muscles electromyographic activations, and the cortical oscillatory activity.
Results
The movement-related beta desynchronization was significantly decreased in post-stroke participants compared to healthy participants. We found a significant correlation between the movement-related beta desynchronization and the elbow flexors activation during the active elbow extension in post-stroke participants. When compared to healthy participants, post-stroke participants exhibited significant alterations in the elbow kinematics and greater muscle activation levels.
Conclusions
Cortical beta oscillation alterations may reflect an important neural mechanism underlying spastic co-contraction after a stroke.
Significance
Measuring the cortical oscillatory activity could be useful to further characterize neuromuscular plasticity induced by recovery or therapeutic interventions.
