Influence of training environment and cognitive deficits on use of feedback for motor learning in chronic stroke

Abstract

Feedback provision is an essential component of motor learning for improving upper limb recovery in people with stroke. Along with sensorimotor impairments, many individuals post-stroke have cognitive deficits that can influence arm motor recovery. However, few studies have identified whether the training environment and presence of cognitive deficits influences the ability to use feedback in individuals post-stroke. We evaluated the influence of the training environment and cognitive impairments on the ability to use feedback to enhance arm motor recovery. Twenty-four subjects with chronic post-stroke upper limb hemiparesis were randomized to practice pointing movements in a 3D virtual environment (VE) or a similarly designed physical environment (PE; n=12/group) for 12 sessions (72 trials/session, 3 days/week). All participants were provided with feedback about movement speed (Knowledge of Results) and trunk displacement (Knowledge of Performance). Neurocognitive functioning was assessed only before task practice (PRE), while kinematic assessments were carried out at PRE, immediately after (POST) and 3 months (RET) after task practice. Repeated measures ANOVAs with mixed models assessed the changes in kinematic outcomes. Neurocognitive function was correlated with kinematic outcomes. Those training in the VE had greater endpoint speed and ranges of shoulder horizontal adduction, shoulder flexion and elbow extension. They also tended to use less trunk displacement. Kinematic deficits influenced the ability to use feedback in people with chronic stroke for upper limb motor learning and recovery. Information about the presence of these deficits can help in the selection of the most appropriate interventions for maximizing arm motor recovery and motor learning in chronic stroke.