Grant: Travel Awards - Institute Community Support

As we age, we may experience a feeling of having to "think" about how we walk. This impedes our ability to make quick changes from one step to the next, like we may have to do to navigate around a puddle in our path. This is especially true for older adults with Parkinson's Disease (PD). Interestingly, both healthy older adults and adults with PD can change their gait pattern to walk on a split-belt treadmill- a treadmill with a separate belt under each leg. This treadmill can drive each foot at a different speed, quickly creating a bizarre asymmetric gait pattern. While we know older adults and adults with PD can change their walking pattern quickly, we are still not sure of how the brain is able to control these step-to-step alterations. In this project, we use brain imaging to compare the brain activity of young adults, older adults and adults with PD during typical treadmill walking (both belts at a comfortable walking speed) to split-belt treadmill walking (belts at different speeds). To quickly modify their walking pattern, all participants increased activity in brain regions responsible for movement planning, consolidating their movements with sensations from their feet and updating their plan for their walking pattern. With age, however, their brain widened this activity to include regions for memory and cognition. Finally, the presence of PD required even further activation from areas responsible for information of sensation from their body and legs. This widespread and increased use of brain resources may help to explain why more complex walking tasks, such as walking and talking or turning, show detriments with aging and the progression of PD. By better understanding how the brain controls the way we walk, we may be able to help those who find these changes to their walking pattern difficult.