Phase resetting of human walking

Abstract

This thesis is an investigation of the neural control of unimpaired human walking. Specifically, this work studied the potential for phase resetting of human walking by analyzing results from treadmill walking experiments. Subjects walked on a treadmill while wearing a robotic device that attaches to the lower leg, which applied 6 Nm torque perturbations to the ankle that acted to plantarflex the ankle. The effect of these perturbations on the stride period was then analyzed to determine the potential for phase resetting of the gait. For the experimental setup used, no phase resetting was found. This was determined by fitting a Fourier series regression to the data and finding very low R² values for all subjects, ranging from 0.04 to 0.10, which implies that no underlying periodic curve exists in the data. This evidence of zero phase resetting is consistent with prior work that indicates some type of kinematic controller is present during walking.