title: Biofeedback Signals for Robotic Rehabilitation: Assessment of Wrist Muscle Activation Patterns in Healthy Humans.
abstract: Electrophysiological recordings from human muscles can serve as control signals for robotic rehabilitation devices. Given that many diseases affecting the human sensorimotor system are associated with abnormal patterns of muscle activation, such biofeedback can optimize human-robot interaction and ultimately enhance motor recovery. To understand how mechanical constraints and forces imposed by a robot affect muscle synergies, we mapped the muscle activity of seven major arm muscles in healthy individuals performing goal-directed discrete wrist movements constrained by a wrist robot. We tested six movement directions and four force conditions typically experienced during robotic rehabilitation. We analyzed electromyographic (EMG) signals using a space-by-time decomposition and we identified a set of spatial and temporal modules that compactly described the EMG activity and were robust across subjects. For each trial, coefficients expressing the strength of each combination of modules and representing the underlying muscle recruitment, allowed for a highly reliable decoding of all experimental conditions. The decomposition provides compact representations of the observable muscle activation constrained by a robotic device. Results indicate that a low-dimensional control scheme incorporating EMG biofeedback could be an effective add-on for robotic rehabilitative protocols seeking to improve impaired motor function in humans.
authors.forename: Marianna
authors.initials: M
authors.lastname: Semprini
authors.forename: Anna Vera
authors.initials: AV
authors.lastname: Cuppone
authors.forename: Ioannis
authors.initials: I
authors.lastname: Delis
authors.forename: Valentina
authors.initials: V
authors.lastname: Squeri
authors.forename: Stefano
authors.initials: S
authors.lastname: Panzeri
authors.forename: Jurgen
authors.initials: J
authors.lastname: Konczak
mesh_terms: D001676:Biofeedback, Psychology / Q000379:methods* / Q000502:physiology; D004576:Electromyography / Q000379:methods; D005260:Female; D006801:Humans; D008297:Male; D009119:Muscle Contraction / Q000502:physiology*; D018482:Muscle, Skeletal / Q000502:physiology*; D000066530:Neurological Rehabilitation / Q000379:methods*; D012016:Reference Values; D012371:Robotics / Q000379:methods*; D014953:Wrist / Q000502:physiology*; D055815:Young Adult