Abstract: Movement control involves a complex interplay of spinal and corticospinal mechanisms and pathways, providing flexibility for normal motor behaviors and plasticity after motor disorders. The parallel yet hierarchical organization of the motor system (Rothwell, 2012; Enoka, 2015) imposes challenges for designing methods and techniques to assess and modulate neuronal circuits since sensorimotor transformations are vastly distributed during reflexive, automatic, and voluntary actions. In this vein, the Research Topic aimed to bring about studies targeting the issue of effectively evaluating the function of spinal and corticospinal circuits involved in movement control under different physiological conditions, along with the alterations experienced by these neuronal circuits when neurorehabilitation/neuromodulation techniques are employed to recover/improve motor function. The eight studies presented in the Research Topic cover three main areas: neuromodulation of locomotor circuits, assessments of spinal cord excitability, and corticospinal activity in motor learning