Abstract
<p>As our population of aging adults continues to grow, finding ways to maintain health-span with our increased lifespan is essential. Central to health span is maintenance of mobility and cognitive function. In addition to maintaining these functions, it is essential to understand indicators of optimal health in domains of mobility and cognition. In aging adults, deficits in mobility and cognition coincide. Specifically, walking and cognitive function are highly intertwined. Even in early stages of disease onset in mild cognitive impairment and dementia, decrements in walking are observable.<sup>1,2</sup><!--[if supportFields]><span
style='mso-element:field-end'></span><![endif]--> Declines in gait speed have also been shown to be predictive of future cognitive decline, up to 12 years prior to disease onset.<!--[if supportFields]><span style='mso-element:field-begin;
mso-field-lock:yes'></span>ADDIN CSL_CITATION
{"citationItems":[{"id":"ITEM-1","itemData":{"DOI":"10.1001/archneurol.2010.159","ISSN":"1538-3687","PMID":"20697049","abstract":"OBJECTIVES
To compare the trajectory of motor decline, as measured by gait speed and
finger-tapping speed, between elderly people who developed mild cognitive
impairment (MCI) and those who remained cognitively intact. We also sought to
determine the approximate time at which the decline in motor function
accelerated in persons who developed MCI. DESIGN Longitudinal cohort study.
PARTICIPANTS Participants were 204 healthy seniors (57.8% women) from the
Oregon Brain Aging Study evaluated for up to 20 years using annual neurologic,
neuropsychological, and motor examinations. MAIN OUTCOME MEASURES The pattern
of motor decline with aging was compared using a mixed-effects model with an
interaction term for age and a clinical diagnosis of MCI. The time before
diagnosis of MCI, when the change in gait or finger-tapping speed accelerates,
was assessed using a mixed-effects model with a change point for men and women,
separately and combined, who developed MCI. RESULTS The rates of change, with
aging, in gait speed (P < .001) and finger-tapping speed in the dominant
hand (P = .003) and nondominant hand (P < .001) were significantly different
between participants who developed MCI (converters) and those who did not
(nonconverters). Using a change point analysis for MCI converters, the decrease
in gait speed accelerated by 0.023 m/s/y (P < .001), occurring 12.1 years
before the onset of MCI. An acceleration in gait speed decline occurred earlier
in men than women. For tapping speed, the change point occurred after the onset
of MCI for both dominant and nondominant hands when men and women were
combined. CONCLUSIONS Motor decline as indexed by gait speed accelerates up to
12 years before MCI. Longitudinal changes in motor function may be useful in
the early detection of dementia during preclinical stages, when the utility of
disease-modifying therapies would be greatest.","author":[{"dropping-particle":"","family":"Buracchio","given":"Teresa","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Dodge","given":"Hiroko
H.","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Howieson","given":"Diane","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Wasserman","given":"Dara","non-dropping-particle":"","parse-names":false,"suffix":""},{"dropping-particle":"","family":"Kaye","given":"Jeffrey","non-dropping-particle":"","parse-names":false,"suffix":""}],"container-title":"Archives
of neurology","id":"ITEM-1","issue":"8","issued":{"date-parts":[["2010","8"]]},"page":"980-6","title":"The
trajectory of gait speed preceding mild cognitive
impairment.","type":"article-journal","volume":"67"},"uris":["http://www.mendeley.com/documents/?uuid=5dfd8a83-5618-3774-8125-46b551f59c1a"]}],"mendeley":{"formattedCitation":"<sup>3</sup>","plainTextFormattedCitation":"3","previouslyFormattedCitation":"<sup>3</sup>"},"properties":{"noteIndex":0},"schema":"https://github.com/citation-style-language/schema/raw/master/csl-citation.json"}<span
style='mso-element:field-separator'></span><![endif]--><sup>3</sup><!--[if supportFields]><span
style='mso-element:field-end'></span><![endif]--></p>
<p>The performance of dual-task (DT) walking, walking while performing a secondary cognitive task, can give simultaneous insights into cognitive and motor function in aging adults. Current research is attempting to utilize DT walking assessments as a way to increase the stress of the walking to improve prediction of future neurodegenerative diseases.<sup>4</sup> While there are longitudinal studies investigated the utility of DT walking as a predictor of decline, there is still much unknown about neurobiological factors that are related to DT walking performance in aging adults.</p>
<p>The goal of this research is to investigate how components of resiliency (cognitive and physical reserve, brain maintenance, and brain reserve) can mediate the effects of aging in the context of DT walking assessments. Experiment 1 investigates the relationship between multiple domains of cognitive and executive function, and performance of DT walking using a measure of mobility, the Timed up-and-go, and a measure of self-selected gait speed. Experiment 2 investigates the relationship of neuroplasticity, a component of brain maintenance, and DT walking performance. Finally, to model altered brain reserve, Experiment 3 investigates the differences in DT performance between healthy aging adults and individuals who have suffered a stroke, using two distinct walking tasks.</p>