Spatial variability and directional shifts in postural control in Parkinson's disease.

Summary: People with Parkinson's disease often have trouble keeping their balance. This study looked at how people stand and sway. Healthy young and older adults usually control their balance by swaying front-to-back and side-to-side. But people with Parkinson's sway in different, tilted directions. Also, when asked to do tricky balance tasks, healthy people change how they stand to stay safe, but people with Parkinson's do not. This shows why they might fall more often and proves their balance issues are very different from normal aging.