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Articles 1 - 30 of 46
Full-Text Articles in Engineering
A Pneumatically Actuated Manipulandum For Neuromotor Control Research, Aaron J Suminski, Kristina Ropella, Robert Scheidt
A Pneumatically Actuated Manipulandum For Neuromotor Control Research, Aaron J Suminski, Kristina Ropella, Robert Scheidt
Robert Scheidt
Functional magnetic resonance imaging (fMRI) techniques have great potential for identifying which neural structures are involved in the control of goal-directed reaching movements. However, fMRI techniques alone are not capable of probing the neural mechanisms involved in acquisition of novel motor behaviors because such studies require that the moving limb be perturbed in a controlled fashion. We outline a plan to design and develop a non-metallic, pneumatically actuated tool that, along with systems identification techniques and functional magnetic resonance imaging (fMRI), will characterize and quantify how the human central nervous system uses sensory information during practice-based motor learning.
Experimental Validation Of A Mr-Compatible Pneumatic Manipulandum For Imaging The Neural Correlates Of Motor Control, Aaron Suminski, Janice Zimbelman, Robert Scheidt
Experimental Validation Of A Mr-Compatible Pneumatic Manipulandum For Imaging The Neural Correlates Of Motor Control, Aaron Suminski, Janice Zimbelman, Robert Scheidt
Robert Scheidt
No abstract provided.
A Real-Time Haptic/Graphic Demonstration Of How Error Augmentation Can Enhance Learning, Yejun Wei, James Patton, Preeti Bajaj, Robert Scheidt
A Real-Time Haptic/Graphic Demonstration Of How Error Augmentation Can Enhance Learning, Yejun Wei, James Patton, Preeti Bajaj, Robert Scheidt
Robert Scheidt
We developed a real-time controller for a 2 degree-of-freedom robotic system using xPC Target. This system was used to investigate how different methods of performance error feedback can lead to faster and more complete motor learning in individuals asked to compensate for a novel visuo-motor transformation (a 30 degree rotation). Four groups of human subjects were asked to reach with their unseen arm to visual targets surrounding a central starting location. A cursor tracking hand motion was provided during each reach. For one group of subjects, deviations from the “ideal” compensatory hand movement (i.e. trajectory errors) were amplified with a …
Remapping Hand Movements In A Novel Geometrical Environment, Kristine Mosier, Robert Scheidt, Santiago Acosta, Ferdinando Mussa-Ivaldi
Remapping Hand Movements In A Novel Geometrical Environment, Kristine Mosier, Robert Scheidt, Santiago Acosta, Ferdinando Mussa-Ivaldi
Robert Scheidt
The issue of how the Euclidean properties of space are represented in the nervous system is a main focus in the study of visual perception, but is equally relevant to motor learning. The goal of our experiments was to investigate how the properties of space guide the remapping of motor coordination. Subjects wore an instrumented data glove that recorded the finger motions. Signals generated by the glove operated a remotely controlled endpoint: a cursor on a computer monitor. The subjects were instructed to execute movements of this endpoint with controlled motions of the fingers. This required inverting a highly redundant …
Visual Error Augmentation For Enhancing Motor Learning And Rehabilitative Relearning, Yejun Wei, Preeti Bajaj, Robert A. Scheidt, James L. Patton
Visual Error Augmentation For Enhancing Motor Learning And Rehabilitative Relearning, Yejun Wei, Preeti Bajaj, Robert A. Scheidt, James L. Patton
Robert Scheidt
We developed a real-time controller for a 2 degree-of-freedom robotic system using xPC Target. This system was used to investigate how different methods of performance error feedback can lead to faster and more complete motor learning in individuals asked to compensate for a novel visuo-motor transformation (a 30 degree rotation). Four groups of normal human subjects were asked to reach with their unseen arm to visual targets surrounding a central starting location. A cursor tracking hand motion was provided during each reach. For one group of subjects, deviations from the "ideal" compensatory hand movement (i.e. trajectory errors) were amplified with …
Remembering Forward: Neural Correlates Of Memory And Prediction In Human Motor Adaptation, Robert A. Scheidt, Janice Zimbelman, Nicole M.G. Salowitz, Aaron J. Suminski, Kristine M. Mosier, James Houk, Lucia Simo
Remembering Forward: Neural Correlates Of Memory And Prediction In Human Motor Adaptation, Robert A. Scheidt, Janice Zimbelman, Nicole M.G. Salowitz, Aaron J. Suminski, Kristine M. Mosier, James Houk, Lucia Simo
Robert Scheidt
We used functional MR imaging (FMRI), a robotic manipulandum and systems identification techniques to examine neural correlates of predictive compensation for spring-like loads during goal-directed wrist movements in neurologically-intact humans. Although load changed unpredictably from one trial to the next, subjects nevertheless used sensorimotor memories from recent movements to predict and compensate upcoming loads. Prediction enabled subjects to adapt performance so that the task was accomplished with minimum effort. Population analyses of functional images revealed a distributed, bilateral network of cortical and subcortical activity supporting predictive load compensation during visual target capture. Cortical regions – including prefrontal, parietal and hippocampal …
Effects Of Wrist Tendon Vibration On Targeted Upper-Arm Movements In Poststroke Hemiparesis, Megan O. Conrad, Robert A. Scheidt, Brian D. Schmit
Effects Of Wrist Tendon Vibration On Targeted Upper-Arm Movements In Poststroke Hemiparesis, Megan O. Conrad, Robert A. Scheidt, Brian D. Schmit
Robert Scheidt
Background. Impaired motor control of the upper extremity after stroke may be related to lost sensory, motor, and integrative functions of the brain. Artificial activation of sensory afferents might improve control of movement by adding excitatory drive to sensorimotor control structures. The authors evaluated the effect of wrist tendon vibration (TV) on paretic upper-arm stability during point-to-point planar movements. Methods. TV (70 Hz) was applied to the forearm wrist musculature of 10 hemiparetic stroke patients as they made center-out planar arm movements. End-point stability, muscle activity, and grip pressure were compared as patients stabilized at the target position for trials …
A Physiologically Based Clinical Measure For Spastic Reflexes In Spinal Cord Injury, Ela Benz, T. Hornby, Rita Bode, Robert Scheidt, Brian Schmit
A Physiologically Based Clinical Measure For Spastic Reflexes In Spinal Cord Injury, Ela Benz, T. Hornby, Rita Bode, Robert Scheidt, Brian Schmit
Robert Scheidt
Objective: To test the validity of the Spinal Cord Assessment Tool for Spastic reflexes (SCATS), a clinical tool intended to rate spastic motor behavior after spinal cord injury (SCI). Design: By using correlational analyses, the SCATS was validated using concurrent measurements of kinematics and electromyograms and traditional assessments of spasms and spastic hypertonia. Setting: Research laboratory (kinematics and electromyography) and outpatient medical clinic (traditional measures of spastic hypertonia). Participants: Eleven people with SCI were used for kinematic and electromyographic measurements. Seventeen people with SCI were used for comparison with other clinical scales. Interventions: Not applicable. Main outcome measures: Kinematic and …
Dataglove Measurement Of Joint Angles In Sign Language Handshapes, Petra Eccarius, Rebecca Bour, Robert A. Scheidt
Dataglove Measurement Of Joint Angles In Sign Language Handshapes, Petra Eccarius, Rebecca Bour, Robert A. Scheidt
Robert Scheidt
In sign language research, we understand little about articulatory factors involved in shaping phonemic boundaries or the amount (and articulatory nature) of acceptable phonetic variation between handshapes. To date, there exists no comprehensive analysis of handshape based on the quantitative measurement of joint angles during sign production. The purpose of our work is to develop a methodology for collecting and visualizing quantitative handshape data in an attempt to better understand how handshapes are produced at a phonetic level. In this pursuit, we seek to quantify the flexion and abduction angles of the finger joints using a commercial data glove (CyberGlove; …
Control Strategies For The Transition From Multijoint To Single-Joint Arm Movements Studied Using A Simple Mechanical Constraint, Robert Scheidt, W. Rymer
Control Strategies For The Transition From Multijoint To Single-Joint Arm Movements Studied Using A Simple Mechanical Constraint, Robert Scheidt, W. Rymer
Robert Scheidt
Changes were studied in neuromotor control that were evoked by constraining the motion of the elbow joint during planar, supported movements of the dominant arm in eight normal human subjects. Electromyograph (EMG) recordings from shoulder and arm muscles were used to determine whether the normal multijoint muscle activity patterns associated with reaching to a visual target were modified when the movement was reduced to a single-joint task, by pinning the elbow to a particular location in the planar work space. Three blocks of 150 movements each were used in the experiments. Subjects were presented with the unconstrained task in the …
Reach Adaptation And Final Position Control Amid Environmental Uncertainty After Stroke, Robert Scheidt, Tina Stoeckmann
Reach Adaptation And Final Position Control Amid Environmental Uncertainty After Stroke, Robert Scheidt, Tina Stoeckmann
Robert Scheidt
We characterized how hemiparetic stroke survivors and neurologically intact individuals adapt reaching movements to compensate for unpredictable environmental perturbations. We tested the hypotheses that like unimpaired subjects, hemiparetic stroke survivors adapt using sensory information obtained during only the most recent movements and that the reliability of target acquisition decreases as the degree of sensorimotor impairment increases. Subjects held the handle of a two-joint robotic arm that applied forces to the hand while reaching between targets in a horizontal plane. The robot simulated a dynamic environment that varied randomly in strength from one trial to the next. The trial sequence of …
Neural And Electromyographic Correlates Of Wrist Posture Control, Aaron Suminski, Stephen Rao, Kristine Mosier, Robert Scheidt
Neural And Electromyographic Correlates Of Wrist Posture Control, Aaron Suminski, Stephen Rao, Kristine Mosier, Robert Scheidt
Robert Scheidt
In identical experiments in and out of a MR scanner, we recorded functional magnetic resonance imaging and electromyographic correlates of wrist stabilization against constant and time-varying mechanical perturbations. Positioning errors were greatest while stabilizing random torques. Wrist muscle activity lagged changes in joint angular velocity at latencies suggesting trans-cortical reflex action. Drift in stabilized hand positions gave rise to frequent, accurately directed, corrective movements, suggesting that the brain maintains separate representations of desired wrist angle for feedback control of posture and the generation of discrete corrections. Two patterns of neural activity were evident in the blood-oxygenation-level-dependent (BOLD) time series obtained …
Temporal And Spatial Aspects Of Sensory Interactions During Human Fusional Response, Robert Scheidt, Andrew Kertesz
Temporal And Spatial Aspects Of Sensory Interactions During Human Fusional Response, Robert Scheidt, Andrew Kertesz
Robert Scheidt
Temporal and spatial aspects of sensory interactions during human fusional response were investigated using band-limited, 10th-derivative-of-Gaussian patterns confined to separate regions of the visual field. Experiments were performed to investigate the time course of sensory interactions using the horizontal sensory fusional amplitude (SFA) and the sensory fusional range (SFR) as measures of the interaction. The nature of sensory interactions across the spatial domain has been found to be a function of stimulus duration and time course. These interactions included both enhancements and reductions of SFAs as well as reductions and shifts in SFRs. Two functional components of sensory fusional interactions …
Separate Adaptive Mechanisms For Controlling Trajectory And Final Position In Reaching, Robert Scheidt, Claude Ghez
Separate Adaptive Mechanisms For Controlling Trajectory And Final Position In Reaching, Robert Scheidt, Claude Ghez
Robert Scheidt
We examined control of the hand's trajectory (direction and shape) and final equilibrium position in horizontal planar arm movements by quantifying transfer of learned visuomotor rotations between two tasks that required aiming the hand to the same spatial targets. In a trajectory-reversal task (“slicing”), the hand reversed direction within the target and returned to the origin. In a positioning task (“reaching”), subjects moved the hand to the target and held it there; cursor feedback was provided only after movement ended to isolate learning of final position from trajectory direction. We asked whether learning acquired in one task would transfer to …
Sensitivity To Hand Path Curvature During Reaching, Kyle P. Lillis, Robert A. Scheidt
Sensitivity To Hand Path Curvature During Reaching, Kyle P. Lillis, Robert A. Scheidt
Robert Scheidt
People optimize reaching to make straight and smooth movements. We performed experiments characterizing human sensitivity to hand path deviations from a straight reach. Vision of the arm was blocked. Subjects either moved the hand along paths of constrained curvature, or a robot moved the relaxed limb along similar trajectories (active and passive conditions, respectively). Subjects responded after each trial whether or not they thought the movement curved convex right. In a series of three experiments, we tested the effects of modifying visual feedback of hand position to suppress curvature, isotonic muscle activation, and a distracter task on subjects ability to …
Effects Of Wrist Tendon Vibration On Arm Tracking In People Poststroke, Megan Conrad, Robert Scheidt, Brian Schmit
Effects Of Wrist Tendon Vibration On Arm Tracking In People Poststroke, Megan Conrad, Robert Scheidt, Brian Schmit
Robert Scheidt
The goal of this study was to evaluate the influence of wrist tendon vibration on a multijoint elbow/shoulder tracking task. We hypothesized that tendon vibration applied at the wrist musculature would improve upper arm tracking performance in chronic stroke survivors through increased, Ia-afferent feedback to the central nervous system (CNS). To test this hypothesis, 10 chronic stroke and 5 neurologically intact subjects grasped the handle of a planar robot as they tracked a target through a horizontal figure-8 pattern. A total of 36 trials were completed by each subject. During the middle trials, 70-Hz tendon vibration was applied at the …
Effects Of Optimal Tactile Feedback In Balancing Tasks: A Pilot Study, Emmanouil Tzorakoleftherakis, Ferdinando Mussa-Ivaldi, Robert Scheidt, Todd Murphey
Effects Of Optimal Tactile Feedback In Balancing Tasks: A Pilot Study, Emmanouil Tzorakoleftherakis, Ferdinando Mussa-Ivaldi, Robert Scheidt, Todd Murphey
Robert Scheidt
In this study, we employ optimal control and tactile feedback to teach subjects how to balance a simulated inverted pendulum. The output of a Linear Quadratic Regulator (LQR) was converted to a vibratory teacher-signal and was provided as additional somatosensory feedback to the subjects. The LQR approach is consistent with an energy-saving strategy commonly observed during human motor learning. Our rationale for using the inverted pendulum as a criterion task is that this balance system requires the brain to solve many of the same problems encountered in simple tasks of daily living like transporting a glass of water to the …
A Robotic Test Of Proprioception Within The Hemiparetic Arm Post-Stroke, Lucia Simo, Lior Botzer, Claude Ghez, Robert A. Scheidt
A Robotic Test Of Proprioception Within The Hemiparetic Arm Post-Stroke, Lucia Simo, Lior Botzer, Claude Ghez, Robert A. Scheidt
Robert Scheidt
Background: Proprioception plays important roles in planning and control of limb posture and movement. The impact of proprioceptive deficits on motor function post-stroke has been difficult to elucidate due to limitations in current tests of arm proprioception. Common clinical tests only provide ordinal assessment of proprioceptive integrity (eg. intact, impaired or absent). We introduce a standardized, quantitative method for evaluating proprioception within the arm on a continuous, ratio scale. We demonstrate the approach, which is based on signal detection theory of sensory psychophysics, in two tasks used to characterize motor function after stroke. Methods: Hemiparetic stroke survivors and neurologically intact …
Elastic, Viscous, And Mass Load Effects On Poststroke Muscle Recruitment And Co-Contraction During Reaching: A Pilot Study, Tina M. Stoeckmann, Katherine J. Sullivan, Robert A. Scheidt
Elastic, Viscous, And Mass Load Effects On Poststroke Muscle Recruitment And Co-Contraction During Reaching: A Pilot Study, Tina M. Stoeckmann, Katherine J. Sullivan, Robert A. Scheidt
Robert Scheidt
Background: Resistive exercise after stroke can improve strength (force-generating capacity) without increasing spasticity (velocity-dependent hypertonicity). However, the effect of resistive load type on muscle activation and co-contraction after stroke is not clear. Objective: The purpose of this study was to determine the effect of load type (elastic, viscous, or mass) on muscle activation and co-contraction during resisted forward reaching in the paretic and nonparetic arms after stroke. Design: This investigation was a single-session, mixed repeated-measures pilot study. Methods: Twenty participants (10 with hemiplegia and 10 without neurologic involvement) reached forward with each arm against equivalent elastic, viscous, and mass loads. …
Reorganization Of Finger Coordination Patterns During Adaptation To Rotation And Scaling Of A Newly Learned Sensorimotor Transformation, Xiaolin Liu, Kristine Mosier, Ferdinando Mussa-Ivaldi, Maura Casadio, Robert Scheidt
Reorganization Of Finger Coordination Patterns During Adaptation To Rotation And Scaling Of A Newly Learned Sensorimotor Transformation, Xiaolin Liu, Kristine Mosier, Ferdinando Mussa-Ivaldi, Maura Casadio, Robert Scheidt
Robert Scheidt
We examined how people organize redundant kinematic control variables (finger joint configurations) while learning to make goal-directed movements of a virtual object (a cursor) within a low-dimensional task space (a computer screen). Subjects participated in three experiments performed on separate days. Learning progressed rapidly on day 1, resulting in reduced target capture error and increased cursor trajectory linearity. On days 2 and 3, one group of subjects adapted to a rotation of the nominal map, imposed either stepwise or randomly over trials. Another group experienced a scaling distortion. We report two findings. First, adaptation rates and memory-dependent motor command updating …
Contributions Of Online Visual Feedback To The Learning And Generalization Of Novel Finger Coordination Patterns, Xiaolin Liu, Robert Scheidt
Contributions Of Online Visual Feedback To The Learning And Generalization Of Novel Finger Coordination Patterns, Xiaolin Liu, Robert Scheidt
Robert Scheidt
We explored how people learn new ways to move objects through space using neuromuscular control signals having more degrees of freedom than needed to unambiguously specify object location. Subjects wore an instrumented glove that recorded finger motions. A linear transformation matrix projected joint angle signals (a high-dimensional control vector) onto a two-dimensional cursor position on a video monitor. We assessed how visual information influences learning and generalization of novel finger coordination patterns as subjects practiced using hand gestures to manipulate cursor location. Three groups of test subjects practiced moving a visible cursor between different sets of screen targets. The hand-to-screen …
Simultaneous Robotic Manipulation And Functional Magnetic Resonance Imaging: Feasibility In Children With Autism Spectrum Disorders, Nicole Salowitz, Bridget Dolan, Rheanna Remmel, Amy Van Hecke, Kristine Mosier, Lucia Simo, Robert Scheidt
Simultaneous Robotic Manipulation And Functional Magnetic Resonance Imaging: Feasibility In Children With Autism Spectrum Disorders, Nicole Salowitz, Bridget Dolan, Rheanna Remmel, Amy Van Hecke, Kristine Mosier, Lucia Simo, Robert Scheidt
Robert Scheidt
An unanswered question concerning the neural basis of autism spectrum disorders (ASD) is how sensorimotor deficits in individuals with ASD are related to abnormalities of brain function. We previously described a robotic joystick and video game system that allows us to record functional magnetic resonance images (FMRI) while adult humans make goal-directed wrist motions. We anticipated several challenges in extending this approach to studying goal-directed behaviors in children with ASD and in typically developing (TYP) children. In particular we were concerned that children with autism may express increased levels of anxiety as compared to typically developing children due to the …
Persistence Of Motor Adaptation During Constrained, Multi-Joint, Arm Movements, Robert Scheidt, David Reinkensmeyer, Michael Conditt, W. Reymer, Ferdinando Mussa-Ivaldi
Persistence Of Motor Adaptation During Constrained, Multi-Joint, Arm Movements, Robert Scheidt, David Reinkensmeyer, Michael Conditt, W. Reymer, Ferdinando Mussa-Ivaldi
Robert Scheidt
We studied the stability of changes in motor performance associated with adaptation to a novel dynamic environment during goal-directed movements of the dominant arm. Eleven normal, human subjects made targeted reaching movements in the horizontal plane while holding the handle of a two-joint robotic manipulator. This robot was programmed to generate a novel viscous force field that perturbed the limb perpendicular to the desired direction of movement. Following adaptation to this force field, we sought to determine the relative role of kinematic errors and dynamic criteria in promoting recovery from the adapted state. In particular, we compared kinematic and dynamic …
Different Learned Coordinate Frames For Planning Trajectories And Final Positions In Reaching, Claude Ghez, Robert Scheidt, Hank Heijink
Different Learned Coordinate Frames For Planning Trajectories And Final Positions In Reaching, Claude Ghez, Robert Scheidt, Hank Heijink
Robert Scheidt
We previously reported that the kinematics of reaching movements reflect the superimposition of two separate control mechanisms specifying the hand's spatial trajectory and its final equilibrium position. We now asked whether the brain maintains separate representations of the spatial goals for planning hand trajectory and final position. One group of subjects learned a 30° visuomotor rotation about the hand's starting point while performing a movement reversal task (“slicing”) in which they reversed direction at one target and terminated movement at another. This task required accuracy in acquiring a target mid-movement. A second group adapted while moving to—and stabilizing at—a single …
Visual, Motor And Attentional Influences On Proprioceptive Contributions To Perception Of Hand Path Rectilinearity During Reaching, Robert A. Scheidt, Kyle P. Lillis, Scott J. Emerson
Visual, Motor And Attentional Influences On Proprioceptive Contributions To Perception Of Hand Path Rectilinearity During Reaching, Robert A. Scheidt, Kyle P. Lillis, Scott J. Emerson
Robert Scheidt
We examined how proprioceptive contributions to perception of hand path straightness are influenced by visual, motor and attentional sources of performance variability during horizontal planar reaching. Subjects held the handle of a robot that constrained goal-directed movements of the hand to the paths of controlled curvature. Subjects attempted to detect the presence of hand path curvature during both active (subject driven) and passive (robot driven) movements that either required active muscle force production or not. Subjects were less able to discriminate curved from straight paths when actively reaching for a target versus when the robot moved their hand through the …
Motivating Rehabilitation By Distorting Reality, James L. Patton, Yejun Wei, Chris Scharver, Robert V. Kenyon, Robert A. Scheidt
Motivating Rehabilitation By Distorting Reality, James L. Patton, Yejun Wei, Chris Scharver, Robert V. Kenyon, Robert A. Scheidt
Robert Scheidt
We have found, through a series of recent experiments, encouraging evidence that the neuro-motor system is motivated to change motor patterns when exposed to visuo-motor tasks. We have also shown that the learning of these tasks can be heightened with forces and/or visual distortions that appropriately manipulate the error. This process does not require intense concentration and it is often considered a game. We describe the next generation of robotic large-workspace, three dimensional haptics/graphics systems for rehabilitation
Visual And Proprioceptive Contributions To Compensatory And Pursuit Tracking Movements In Humans, Megan L. Heenan, Robert A. Scheidt, Scott A. Beardsley
Visual And Proprioceptive Contributions To Compensatory And Pursuit Tracking Movements In Humans, Megan L. Heenan, Robert A. Scheidt, Scott A. Beardsley
Robert Scheidt
An ongoing debate in the field of motor control considers how the brain uses sensory information to guide the formation of motor commands to regulate movement accuracy. Recent research has shown that the brain may use visual and proprioceptive information differently for stabilization of limb posture (compensatory movements) and for controlling goal-directed limb trajectory (pursuit movements). Using a series of five experiments and linear systems identification techniques, we modeled and estimated the sensorimotor control parameters that characterize the human motor response to kinematic performance errors during continuous compensatory and pursuit tracking tasks. Our findings further support the idea that pursuit …
A Quantitative And Standardized Robotic Method For The Evaluation Of Arm Proprioception After Stroke, Lucia Simo, Claude Ghez, Lior Botzer, Robert Scheidt
A Quantitative And Standardized Robotic Method For The Evaluation Of Arm Proprioception After Stroke, Lucia Simo, Claude Ghez, Lior Botzer, Robert Scheidt
Robert Scheidt
Stroke often results in both motor and sensory deficits, which may interact in the manifested functional impairment. Proprioception is known to play important roles in the planning and control of limb posture and movement; however, the impact of proprioceptive deficits on motor function has been difficult to elucidate due in part to the qualitative nature of available clinical tests. We present a quantitative and standardized method for evaluating proprioception in tasks directly relevant to those used to assess motor function. Using a robotic manipulandum that exerted controlled displacements of the hand, stroke participants were evaluated, and compared with a control …
Interaction Of Visual And Proprioceptive Feedback During Adaptation Of Human Reaching Movements, Robert Scheidt, Michael Conditt, Emanuele Secco, Ferdinando Mussa-Ivaldi
Interaction Of Visual And Proprioceptive Feedback During Adaptation Of Human Reaching Movements, Robert Scheidt, Michael Conditt, Emanuele Secco, Ferdinando Mussa-Ivaldi
Robert Scheidt
People tend to make straight and smooth hand movements when reaching for an object. These trajectory features are resistant to perturbation, and both proprioceptive as well as visual feedback may guide the adaptive updating of motor commands enforcing this regularity. How is information from the two senses combined to generate a coherent internal representation of how the arm moves? Here we show that eliminating visual feedback of hand-path deviations from the straight-line reach (constraining visual feedback of motion within a virtual, “visual channel”) prevents compensation of initial direction errors induced by perturbations. Because adaptive reduction in direction errors occurred with …
Computerized Biofeedback Knee Goniometer: Acceptance And Effect On Exercise Behavior In Post-Total Knee Arthroplasty Rehabilitation, Todd Kuiken, Hagay Amir, Robert Scheidt
Computerized Biofeedback Knee Goniometer: Acceptance And Effect On Exercise Behavior In Post-Total Knee Arthroplasty Rehabilitation, Todd Kuiken, Hagay Amir, Robert Scheidt
Robert Scheidt
Objective To assess device accuracy, patient acceptance, and effect of a computerized biofeedback knee goniometer (CBG), on patients’ compliance with active range of motion (AROM) exercises after total knee arthroplasty (TKA). Design Two-stage study: measurement validation on asymptomatic controls and an unblinded, multiple crossover trial. Setting Inpatient rehabilitation. Participants Asymptomatic controls (n=14) and post-TKA inpatients (n=11). Interventions For measurement validation, CBG-angle measurements were compared with manual, clinician-obtained angles. To assess motivational effect, the CBG was worn after TKA; on alternating days, it either monitored AROM silently (no feedback) or provided audiovisual feedback about reaching preset range of motion (ROM) goals …