Gait changes among older adults during a virtual wayfinding task: The role of spatial disorientation and heart rate variability

Abstract

AbstractBackgroundAging has been associated with decline in cognitive and motor performance, often expressed in dual‐task walking situations, such as wayfinding. A major barrier to successful wayfinding is spatial disorientation, occurring mostly at intersections. Although gait changes have been observed in various walking conditions, little is known about the effect of spatial disorientation on gait in wayfinding among older adults.Method24 participants (16 female) were measured in 3 conditions: 6 young controls (mean age = 23.50 years, SD = 0.54), 9 old controls (mean age = 68.77 years, SD = 2.72; mean MMSE = 28.85, SD = 0.89) and 8 old experimental (mean age = 71.87 years, SD = 5.38; mean MMSE = 29.14, SD = 0.80). Participants performed a wayfinding task consisting of about 14 decision points (i.e. intersections) within a virtual environment (VE), on a self‐paced treadmill equipped with a marker‐based optical motion‐capture system. The VE was held constant for the controls, and manipulated (e.g. moved landmarks) for the experimental participants. Heart rate was continuously monitored as a measure of psychophysiological response. Statistical analyses using Linear Mixed Effects Models and t‐tests, focused on hypothesis‐driven outcome measures extracted from decision points.ResultInitial evaluation of the outcome measures show considerable effects of the disorientation intervention on gait; both the old control (constant VE) and experimental (manipulated VE) participants showed some variation in walking speed during instances of disorientation. This effect was, however, more pronounced, t(39) = ‐3.66, p<.001, for the old experimental condition participants (Figure 1).ConclusionUnderstanding underlying motion and psychophysiological signatures of spatial disorientation among older adults is a necessary first step, towards developing efficient situation‐aware assistive devices necessary for independent mobility. Initial findings show increased gait variability during instances of disorientation. The association of the disorientation effect with psychophysiological response is also being investigated. Further results will be presented by July 2021.