Kamolnat Tabattanon, Research Trainee

Bernard J. Martin, Principal Investigator

The population and proportion of older adults (age 65+ years) is increasing in the US. Alongside this trend, Americans are increasingly working into older age, with 20% of older adults either working or looking for work[30]. To safely accommodate the projected rise in older workers, it is critical to account for the intersection of old age and mobility disability, as mobility disability incidence is increasing among aging adults[1]. Manual wheelchair support for balance and mobility will be on the rise, though workers who transition to manual wheelchair use will be able to retain independence in movement and upper extremity tasks provided the environment-task demands are designed for inclusion[22, 24]. By addressing this subgroup of older adults with later-in-life incidence of disability, work environment evaluations can become more sustainably inclusive. Current work environments are lacking in this regard, as 22% of older adults with disabilities who ceased seeking work stopped due to discouragement, including from perceived discrimination for age and/or disability[5]. Of further concern, recent studies suggest that disability populations are prone to underreporting their own difficulties when evaluating designs with traditional subjective measures [18, 34]. Yet the use of objective measures (e.g., biomechanics, task times) can be costly during design development. Better alignment between subjective ratings and objective performance can (1) result in designs that promote self-efficacy and remove psychosocial barriers; and (2) support future environment-task design processes towards broader inclusion. 

Therefore, we will investigate mobility performance between those with earlier-in-life (EL) and later-in-life (LL) incidence of manual wheelchair usage. Here, performance in an independent path following task is divided into assumed performance (how participants expect to perform), perceived performance (how participants think they performed), and effective performance (how objective measures quantify their completed performance). By comparing these categories, we will investigate internal representation of motor actions and test differences between groups. This will inform ways to support mobility through environmental indications as well as ways to supplement potentially biased subjective estimations in environmental evaluations. It is postulated that representation of the world as a function of assumed mobility impairment/deficiency is a factor in self-limiting mobility.