Effects of the brain-damaged side after stroke on the learning of a balance task in a non-immersive virtual reality environment

Abstract

Background: Post-stroke survivors with right hemisphere injury have more impairments in postural control and balance. However, the impact of the hemisphere injured on the process of balance reacquisition has not been fully explored. We hypothesized that stroke survivors could learn balance tasks (H1), but right hemisphere damaged patients would show poor motor learning if compared to left hemisphere damaged patients (H2)Objective: To investigate whether the brain-damaged side after stroke affects the learning of a balance task. Methods: Three groups were recruited: twenty stroke survivors (ten left and ten right hemisphere damage) and twenty healthy volunteers. The participants practiced a balance task for thirty minutes, four consecutive days. The task was the Table Tilt game (Nintendo^TM Company), which induces balance demands with a progression of complexity. Motor performance was assessed at baseline, post-practice and after one week (retention test). Accuracy, errors, and complexity of the task achieved during the trial were assessedResults: Participants in all groups improved their performance (p < .001) and maintained it at the retention test. The control group showed better performance if compared to the right and left hemisphere damaged stroke survivors (p < .05). There was no difference between individuals with right and left hemisphere damaged, but the right hemisphere damaged patients demonstrated more errors at higher levels of complexityConclusion: Stroke survivors can learn balance tasks (H1), and the right hemisphere damaged patients demonstrate more errors than those with left hemisphere injury in higher complexity conditions (H2).

Keywords: Motor learning; functional asymmetry; functional cerebral specialization; postural control; stroke.