title: Control of Leg Movements Driven by EMG Activity of Shoulder Muscles.
abstract: During human walking, there exists a functional neural coupling between arms and legs, and between cervical and lumbosacral pattern generators. Here, we present a novel approach for associating the electromyographic (EMG) activity from upper limb muscles with leg kinematics. Our methodology takes advantage of the high involvement of shoulder muscles in most locomotor-related movements and of the natural co-ordination between arms and legs. Nine healthy subjects were asked to walk at different constant and variable speeds (3-5 km/h), while EMG activity of shoulder (deltoid) muscles and the kinematics of walking were recorded. To ensure a high level of EMG activity in deltoid, the subjects performed slightly larger arm swinging than they usually do. The temporal structure of the burst-like EMG activity was used to predict the spatiotemporal kinematic pattern of the forthcoming step. A comparison of actual and predicted stride leg kinematics showed a high degree of correspondence (r > 0.9). This algorithm has been also implemented in pilot experiments for controlling avatar walking in a virtual reality setup and an exoskeleton during over-ground stepping. The proposed approach may have important implications for the design of human-machine interfaces and neuroprosthetic technologies such as those of assistive lower limb exoskeletons.
authors.affiliation: Laboratory of Neuromotor Physiology, Santa Lucia Foundation , Rome , Italy ; Centre of Space Bio-Medicine, University of Rome Tor Vergata , Rome , Italy.
authors.forename: Valentina
authors.initials: V
authors.lastname: La Scaleia
authors.affiliation: Laboratory of Neuromotor Physiology, Santa Lucia Foundation , Rome , Italy ; Centre of Space Bio-Medicine, University of Rome Tor Vergata , Rome , Italy.
authors.forename: Francesca
authors.initials: F
authors.lastname: Sylos-Labini
authors.affiliation: Laboratory of Neurophysiology and Movement Biomechanics, Université Libre de Bruxelles , Brussels , Belgium.
authors.forename: Thomas
authors.initials: T
authors.lastname: Hoellinger
authors.affiliation: Department of Biomechanical Engineering, University of Twente , Enschede , Netherlands.
authors.forename: Letian
authors.initials: L
authors.lastname: Wang
authors.affiliation: Laboratory of Neurophysiology and Movement Biomechanics, Université Libre de Bruxelles , Brussels , Belgium.
authors.forename: Guy
authors.initials: G
authors.lastname: Cheron
authors.affiliation: Laboratory of Neuromotor Physiology, Santa Lucia Foundation , Rome , Italy ; Centre of Space Bio-Medicine, University of Rome Tor Vergata , Rome , Italy ; Department of Systems Medicine, University of Rome Tor Vergata , Rome , Italy.
authors.forename: Francesco
authors.initials: F
authors.lastname: Lacquaniti
authors.affiliation: Laboratory of Neuromotor Physiology, Santa Lucia Foundation , Rome , Italy.
authors.forename: Yuri P
authors.initials: YP
authors.lastname: Ivanenko
keywords: EMG patterns; arm–leg co-ordination; gait kinematics; neuroprosthetic technology; quadrupedal locomotion