Assessment of the Usage of Indirect Motor Pathways in Hemiparetic Stroke

Recent studies found that progressive recruitment of contralesional corticoreticulospinal pathways drives motor impairments post hemiparetic stroke. Thus, a clinically applicable quantitative assessment of the usage of these indirect motor pathways would be highly useful in evaluating the effect of new therapeutic interventions that aim to reduce their usage and associated motor impairments such as the loss of fine motor control of the paretic arm. Our basic research indicates that oligo-synaptic interactions via indirect motor pathways likely enhanced nonlinear neural connectivity and increased neural transmission delays during movement. The specific aim of this Dixon project, therefore, is to translate this basic scientific finding into a novel clinically applicable approach that can quantitatively assess the recruitment of indirect motor pathways, using a simple clinical setup. The impact of this proposal will be to provide clinicians, for the first time, with a relatively easy-to-use tool for the determination of 1) the usage of indirect motor pathways post hemiparetic stroke and 2) the effect of neuro-rehabilitation interventions that reduce their usage. This will then facilitate the development of more targeted neuro-rehabilitation treatments for reducing the usage of indirect motor pathways in favor of remaining corticospinal resources from the lesioned hemisphere during stroke recovery.