Development of an implicit method for directing weight shifting to the affected side in patients with stroke: a proof of concept study

Weight-shift training during stroke rehabilitation requires patient effort, potentially causing leg spasticity and anxiety, which disturb motor learning. The purpose of this study was (1) to devise an implicit guidance method for weight bearing that uses vibratory cues (and is therefore low exertion) and (2) to determine if the implicit guidance method is feasible. The first experiment included 12 healthy subjects. We conducted an experiment to produce a Weber’s fraction capable of calculating a just-noticeable difference during a weight-shifting task. We then applied this Weber’s fraction to a weight-shifting task in a patient with stroke. Using the implicit guidance method, the patient did not perceive an increase in weight bearing while weight shifting. Furthermore, the implicit guidance method appeared to reduce anxiety during training. This implicit guidance system warrants further investigation.