Neurological injuries (such as hemispheric stroke and spinal cord injury, etc.) can result in muscle weakness and spasticity. The affected muscles often experience progressive changes in their intrinsic mechanical properties, giving rise to muscle contracture and associated alterations in muscle internal structural changes. The mechanisms behind the changes are multifactorial, including disuse, autonomic changes, peripheral neuropathy, a loss of central motor neuron trophic influences, and/or their combinations. Regardless of the origins of weakness and other changes, it is very important to understand or quantify complex neuromuscular changes after a neurological injury.

In this Research Topic, we will focus on examination of skeletal muscle changes after neurological injuries because it is the primary organ involved in the generation of force for movement and is also the main effector organ of impairment after neurological injuries, resulting in disability. Of particular interest, the Research Topic will focus on examination of changes in different motor unit components because motor unit is the final common pathway for neuromuscular control and it provides a basic structure-function framework for the examination of neural and muscular disorders. Understanding the changes in different motor unit components (such as motor unit number, size, territory, control properties, etc.) can help identify specific mechanisms causing functional and anatomical changes in the affected muscles, and thereby guiding development of effective treatments for individuals with different neurological injuries.

We encourage submissions that explore the breadth and depth of this research area. The following topics are particularly encouraged. Other topics related to neuromuscular signal processing and control for neurorehabilitation are also welcome.

• Novel methods and techniques for examination of different (such as neural, contractile or mechanical) properties of a motor unit, a muscle or a muscle group;
• Computer simulations and experiments for better understanding of neurological injury in-duced muscle/motor unit alterations;
• Design of rehabilitation strategies targeting specific muscle/motor unit properties;
• Muscle signal (such as electromyography, mechanomyography, impedance, force, etc.) re-cording and processing;
• Animal models for understanding motor unit/muscle property changes after a neurologic injury.

Keywords: Neurological injuries, neurorehabilitation, disability, motor unit, muscle

Important Note: All contributions to this Research Topic must be within the scope of the section and journal to which they are submitted, as defined in their mission statements. Frontiers reserves the right to guide an out-of-scope manuscript to a more suitable section or journal at any stage of peer review.