title: Effects of aging and dual tasking on step adjustments to perturbations in visually cued walking.
abstract: Making step adjustments is an essential component of walking. However, the ability to make step adjustments may be compromised when the walker's attentional capacity is limited. This study compared the effects of aging and dual tasking on step adjustments in response to stepping-target perturbations during visually cued treadmill walking. Fifteen older adults (69.4 ± 5.0 years; mean ± SD) and fifteen young adults (25.4 ± 3.0 years) walked at a speed of 3 km/h on a treadmill. Both groups performed visually cued step adjustments in response to unpredictable shifts of projected stepping targets in forward (FW), backward (BW) or sideward (SW) directions, at different levels of task difficulty [which increased as the available response distance (ARD) decreased], and with and without dual tasking (auditory Stroop task). In both groups, step adjustments were smaller than required. For FW and BW shifts, older adults undershot more under dual-task conditions. For these shifts, ARD affected the age groups differentially. For SW shifts, larger errors were found for older adults, dual tasking and the most difficult ARD. Stroop task performance did not differ between groups in all conditions. Older adults have more difficulty than young adults to make corrective step adjustments while walking, especially under dual-tasking conditions. Furthermore, they seemed to prioritize the cognitive task over the step adjustment task, a strategy that may pose aging populations at a greater fall risk. For comparable task difficulty, the older adults performed considerably worse than the young adults, indicating a decreased ability to adjust steps under time pressure.
authors: Department of Human Movement Sciences, MOVE Research Institute Amsterdam, VU University Amsterdam, Amsterdam, The Netherlands. m.mazaheri@vu.nl.
authors: Masood
authors: M
authors: Mazaheri
authors: Department of Kinesiology, KU Leuven, Leuven, Belgium.
authors: Wouter
authors: W
authors: Hoogkamer
authors: Department of Kinesiology, KU Leuven, Leuven, Belgium.
authors: Zrinka
authors: Z
authors: Potocanac
authors: Department of Rehabilitation Sciences, KU Leuven, Leuven, Belgium.
authors: Sabine
authors: S
authors: Verschueren
authors: Department of Human Movement Sciences, MOVE Research Institute Amsterdam, VU University Amsterdam, Amsterdam, The Netherlands.
authors: Melvyn
authors: M
authors: Roerdink
authors: Department of Human Movement Sciences, MOVE Research Institute Amsterdam, VU University Amsterdam, Amsterdam, The Netherlands.
authors: Peter J
authors: PJ
authors: Beek
authors: Department of Human Movement Sciences, MOVE Research Institute Amsterdam, VU University Amsterdam, Amsterdam, The Netherlands.
authors: C E
authors: CE
authors: Peper
authors: Department of Kinesiology, KU Leuven, Leuven, Belgium.
authors: Jacques
authors: J
authors: Duysens
mesh_terms: D000328:Adult; D000368:Aged; D000375:Aging / Q000502:physiology*; D001307:Auditory Perception / Q000502:physiology; D003463:Cues; D056344:Executive Function / Q000502:physiology*; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D011597:Psychomotor Performance / Q000502:physiology*; D057190:Stroop Test; D014796:Visual Perception / Q000502:physiology*; D016138:Walking / Q000502:physiology*; D055815:Young Adult
keywords: Aging; Attention; Dual tasking; Step adjustment; Visually guided walking