Human Sense of Balance

This overview describes human posture control mechanisms combining biomechanics with neural control and sensory feedback aspects. The control enables humans to automatically balance during standing and walking in the presence of external disturbances such as gravity. Understanding postural mechanisms is important for identifying and treating balance disorders in patients and elderly subjects and for construction of therapeutic and rehabilitation devices. The overview describes the most relevant sensors for balancing and their use in two complementary dynamic control models of perturbed stance. The first model rigorously analyzes human reactive sway behavior and describes it as the effect of feedback from the vestibular, proprioception, and visual sensors and extant sensory reweighting rules. The second model combines posture control with movement execution control, using fusion of sensory signals to estimate and compensate external and self-produced disturbances.