Investigating the Impact of Visual Biofeedback on Postural Control Via Informative Dynamic Balance Training in Healthy Individuals

Objective: After traumatic brain injury (TBI), postural instability often results. This can effect ambulation and, subsequently, activities of daily living. Various forms of rehabilitation have been developed, but few offer engaging activities that provide informative dynamic balance training. The goal of this pilot study was to build a goal-based system that provided visual biofeedback to create an enriched environment for dynamic postural rehabilitation. The study aimed to determine if visual biofeedback had an effect on posture and balance during training for healthy participants; as well as determine the optimal man-machine visual-biofeedback interface. Method: A modified elliptical trainer was developed that incorporated visual-biofeedback from measured left and right lower extremity loads. Four visual displays were constructed and tested on a sample of 15 healthy participants. These displays provided targeted feedback to aid in symmetric performance. The displays differed in the amount of information provided and in the extent of algorithmic pre-processing. Data were evaluated by calculating the index of symmetry (IOS) and statistically comparing display types. Results: Participants performed significantly better with the introduction of visual biofeedback than baseline measurements with no display based on index of symmetry values. The data suggests that the feedback display that incorporated both temporal historical data and differential pre-processing performed the best. This display was called the differential-temporal display. Conclusion: Our results reflect that performance is enhanced with the introduction of visual biofeedback during dynamic postural training. We also established that the differential-temporal display was the optimal feedback system to reduce IOS values during elliptical trainer use. From our results, it became apparent that incorporating visual biofeedback during postural training is a sophisticated approach to improve baseline asymmetries inherent in healthy participants. It is anticipated that similar results are likely to occur in a cohort of TBI patients due to the reduction of cognitive demand.