Title: Neural Correlates of Mobility Impairments in Aging Adults.
For his fellowship, Dr. Shah will use functional MRI to study brain activation patterns of walking. To do this, he will use a motor imagery protocol (imagined walking) that has demonstrated parallel neural substrates to physical task execution. He will compare brain activity differences during imagined walking between young and older adults. The premise is that aging is associated with neural compensation mechanisms particular cognitive regions (e.g., pre-frontal cortex), sensorimotor regions (e.g., Supplemental motor area, posterior parietal cortex), or a combination of both. He will also compare between older adults with confirmed deficits in mobility function and their higher functioning counterparts. Comparing brain activity across mobility function capacity will determine the extent to which compensatory brain over activation and resource ceiling varies with mobility function. He will complete his research project by characterizing brain activity during imagined walking in older adults across a range of mobility abilities. He will test differences in patterns of brain activation during a sensorimotor (imagined walking) task. He hypothesizes that older adults will exhibit compensatory brain over activation as imagined walking task difficulty increases and will have a lower resource ceiling at higher task difficulties.
In his second aims, he will assess the relationship between brain activity and mobility function. Previous studies show more “youth-like” brain activity patterns and reduced mobility disability in more active well-functioning older adults. He hypothesizes that higher functioning older adults will have a greater capacity for brain over activation during imagined walking, which ultimately provides a higher resource ceiling. He will evaluate this association with traditional clinic-based mobility tests (e.g. 400 m walking speed) and free-living mobility measures (e.g. average steps per day, average time outside home, etc.).
The training has made significant progress by conducting MRI testing and performing clinical mobility assessments on older adults. When sufficient data is accumulated — which is projected to be in approximately one year, he will begin conducting MRI analyses and reducing free-living mobility data to complete his aims.