The Effects of Trait and State Anxiety on Gait in Healthy Young Adults

Having an anxious state of mind, often elicited using a height-induced threat, has been consistently shown to alter static and dynamic postural stability in both young and older adults; however, the effects on walking have been less studied. Interestingly, even more stable characteristics such as trait anxiety, in the absence of threat, have been shown to impact gait in clinical populations, although little work has been conducted on young, healthy adults. Attentional processes have also been suggested to play a role in posture and gait control, and anxiety (both state and trait) is known to consume attentional resources and reduce functional cognitive capacity. However, the interaction between trait and state anxiety, and attention on gait has not yet been investigated formally. Therefore, the current study examined the role of trait anxiety as a predictor in gait behaviour during both single- and dual-task walking at the ground and elevated levels, stimulated within a virtual reality (VR) environment. Using a repeated measures design, 30 young, neurotypical adults aged 19-28 completed five walking trials on the Zeno pressure sensor walkway during four different VR-stimulated condition blocks. Conditions were completed in the fixed order of: (i) low threat – walking across a plank on the ground, (ii) low threat + dual-task – walking across a grounded plank while simultaneously monitoring numbers on an audio track, (iii) high threat – walking across a plank elevated above a deep pit, (iv) high threat + dual-task – walking across an elevated plank while simultaneously monitoring numbers on an audio track. At baseline, trait anxiety levels were determined by the State Trait Anxiety Inventory (STAI) and baseline cognitive task performance was recorded while seated. After every trial, state anxiety levels were reported using self-assessment manikins. In general, self-reported anxiety levels increased when walking during the elevated conditions compared to the ground. Trait anxiety was a significant predictor of reductions in gait velocity and iv increased time spent in double support when at elevated conditions during compared to the ground, as well as when dual task walking compared to single task walking at elevation. In addition to reductions in gait velocity and increased time spent in double support, trait anxiety also predicted increased step length variability while dual tasking at elevated conditions compared to dual task walking on the ground. However, the study did not find that trait anxiety was a significant predictor of any spatiotemporal aspects of gait during ground level single task walking, nor when considering dual task walking compared to single task walking at the ground level. The results of this study suggest that trait anxiety does not predict gait behaviour when walking on the ground both with and without attentional tasks. Rather, trait anxiety can predict a slower, more cautious gait pattern under elevated stress (threat) conditions and when performing a dual task during threat