Our long term goal is to develop and market computer-automated systems for retraining posture and equilibrium functions in patients with a variety of disorders including peripheral vestibular deficits, head injury, stroke, and age-related degenerative disorders. The proposed retraining system will be menu-driven and operable by the patient under the supervision of a therapist. The protocols will help the patient learn to compensate for abnormal sensory interaction or movement coordination affecting posture. The quantitative measures provided will assist both therapist and patient in monitoring progress. The phase I grant period will produce a detailed product description for a commercially feasible, automated retraining system. Specific goals include: 1) Define protocols to improve functional balance skills by retraining specific components of abnormal sensory and motor function; 2) Define the means to provide patients with necessary feedback information during retraining; 3) Define algorythms by which the difficulty and scope of protocols can be automatically adjusted as the patient's performance improves; 4) Define absolute measures of performance by which to score the patient in relation to himself and age-matched normals; 5) Identify the mechanical, electronic, and computer hardware necessary to implement the automated retraining protocols.