Successful adaptation of gait in healthy older adults during dual-task treadmill walking

Abstract

Dual-task methods have been used to demonstrate increased prioritization of walking performance over cognition in healthy aging. This is expressed as greater dual-task costs in cognitive performance than in walking. However, other research shows that older adults can prioritize cognitive performance over walking when instructed to do so. We asked whether age-related cognitive prioritization would emerge by experimentally manipulating cognitive difficulty. Young and older adults performed mental arithmetic at two levels of difficulty, alone or while walking. Electromyography and footswitches were used to measure muscle activity and stride parameters. Under high cognitive load, older adults increased their stride time, stride length, and hamstring activity, while maintaining their cognitive performance. Young adults showed negligible dual-task costs in each domain. The older adults appeared to successfully adapt their stride in response to high cognitive demands. The results have implications for neural models of gait regulation, and age differences in task emphasis.

Observing prioritization effects on cognition and gait: The effect of increased cognitive load on cognitively healthy older adults’ dual-task performance

“…We suggest that these healthy older adults prioritized gait over the cognitive task (in the PC condition), to secure gait stability, which was under threat from a heavier demand on their attentional resources. This supports previous findings that healthy older adults will adapt their walking in response to high cognitive demands [24]. Our results also provide further evidence for the 'posture-first' strategy whereby, if the cognitive load during a DT presents a threat to gait security, 'postural control would be the first priority for attentional resources' [10] (p. 238).…”

Psychophysiological response to cognitive workload during symmetrical, asymmetrical and dual-task walking

“…This can also be concluded from the scores on the MRT, where the accuracy significantly decreased during asymmetrical walking. Next to that, the mean age of our subjects was 24.5 ± 2.9 years: previous studies pointed out that temporal gait parameters of younger subjects might be stable under moderate dual-task conditions (Lajoie, Teasdale, Bard, & Fleury, 1996;Li, Abbud, Fraser, & DeMont, 2013;Regnaux, Roberston, Smail, Daniel, & Bussel, 2006).…”

Cellular Telephone Dialing Influences Kinematic and Spatiotemporal Gait Parameters in Healthy Adults

“…Although dual task studies tend to focus on gait changes rather than changes in performance on the other task, the few studies that consider this variable amongst healthy adults indicate that performance may or may not change, depending on the nature of the task and the age of the participants. Decreased dual task performance on serial subtraction tasks have been reported (Srygley, Mirelman, Herman, Giladi, & Hausdorff, 2009;Theill, Martin, Schumacher, Bridenbaugh, & Kressig, 2011), however others have noted no change on these tasks while dual tasking (Li, Abbud, Fraser, & DeMont, 2012;van Iersel, Kessels, Bloem, Verbeek, & Olde Rikkert, 2008). Increased reaction time has also been reported (Faulkner et al, 2006;Patel, Lamar, & Bhatt, 2014), but in three studies semantic fluency was not significantly changed while dual tasking (Krampe, Schaefer, Lindenberger, & Baltes, 2011;Theill et al, 2011;van Iersel et al, 2008).…”

“…It is not entirely clear what these results suggest about participants' relative prioritization of the two tasks, a topic that has received some attention (Amboni et al, 2013;Kelly, Eusterbrock, & Shumway-Cook, 2012;Li et al, 2012;Plummer-D'Amato et al, 2008;Yogev-Seligmann et al, 2012). In this regard, it is important to note that participants were not given any instruction regarding task prioritization.…”