Grant: Operating Grant Priority Announcement: Mobility in Aging

Falls is a common geriatric syndrome and approximately 30% of community-dwellers over the age of 65 experience one or more falls per year. Global cognitive impairment defined as a Folstein's Mini-Mental State Examination (MMSE) score < 24/30 is a key risk factor for falls. But recent evidence suggests that even mild reductions in cognitive abilities among seniors without a diagnosis of cognitive impairment increase falls risk. Specifically, evidence suggests that reduced executive functioning -- the ability to concentrate, to attend selectively, and to plan and strategize -- is associated with increased falls risk among seniors with "intact" global cognitive function (i.e., MMSE score equal to or greater than 24/30). This is a critical public health issue because a large number and proportion of seniors are without frank global cognitive impairment. Currently, the neural basis for the association between reduced executive functioning and falls is unknown. In our previous work using functional MRI, we showed that senior fallers demonstrated a different neural activity pattern while performing a task of executive function from senior non-fallers. Specifically, fallers had a significantly lower hemodynamic response in the right posterior cerebellum. This is a significant finding because the cerebellum is not only responsible for normal motor function (i.e., movement), it also involved in executive functioning (e.g., planning of movement), and hence, may represent a critical interface between mobility and cognition. We propose that identifying regional differences in neural activity between recurrent fallers and non-fallers would refine the focus of future research in the area of cognition and mobility among seniors and in turn lead to the refinement and development of behavioural, cognitive, or neuropharmacological interventions for falls prevention.