Effects of age and task difficulty on postural sway, variability and complexity

Abstract

This study aimed to examine the effects of age and the task difficulty on postural sway, variability and complexity. The participants were 90 able-bodied individuals including children ( n = 39; age: 5.89 ± 0.94 years), young adults ( n = 30; age: 23.23 ± 1.61 years) and older adults ( n = 21; age: 64.59 ± 5.24 years) who took part in different balance tasks that had different levels of cognitive and physical challenges. The main dependent variables were postural sway area, postural variability and postural complexity. The participants stood on a standard force plate for 10 s in each task condition, and the centre of pressure displacement was collected at 100-Hz sampling frequency. The results of this study showed that children and older adults, in the more difficult tasks, had greater sway area and complexity and less postural variability. In addition, there was a linear trend in the stability measures as the difficulty of the task was increased. In conclusion, special populations, such as children and older adults, were more sensitive to the balance changes and used active control mechanisms to minimise the risk of losing balance in more challenging conditions.

Visuomotor control dynamics of quiet standing under single and dual task conditions in younger and older adults

“…gaze) complexity. Since ageing results in lower automaticity of postural sway [1][2][3]57] it is likely a greater cortical contribution is required to maintain balance in older adults [1,54,57]. This is in turn reflected in the greater coupling between sensory input and motor output, in agreement with studies demonstrating high reliance on visual information for postural control in older adults [58].…”

“…As in previous studies, AP sway complexity increased in dual task conditions, indicative of increased postural control automaticity with increased cognitive demand [1][2][3]. However, the results of this study indicated no change in ML or VT sway complexity .…”

“…Postural control requires the complex integration of sensory information to maintain stability. Previous research has demonstrated that cognitive motor interference, elicited by cognitive dual tasking, increases the complexity of postural sway in younger and older adults, which has been suggested to be indicative of increased automaticity of postural sway, or a reduced contribution of cognitive resources to postural control [1][2][3]. Older adults also demonstrate lower postural control complexity than younger adults [4,5], less complex postural control is interpreted as more constrained and less robust [6].…”

Standing Posture in Motor and Cognitive Dual-Tasks during Smartphone Use: Linear and Nonlinear Analysis of Postural Control

“…We suggest that future studies compare different data collection times to provide an adequate record length for entropy analysis. The motor system uses different strategies for postural stability [ 60 ]. Thus, we also recommend studies that use the same methodology and analyze postural control using other nonlinear measures to better understand the postural control’s behavior or adaptive capacity during the dual-task performance.…”

The impact of anxiety on postural control: CO2 challenge model

“…These contrasting findings may be explained by the difference in sample populations. It has been demonstrated that postural control dynamics differ between children and adults (Bisi & Stagni, 2016 ; Shafizadeh et al, 2021 ), with children using more active, less automatic postural control mechanisms than young adults (Shafizadeh et al, 2021 ). The current population of young adults likely had sufficiently robust postural control systems to allow for a decrease in stability, as a result of less active control of posture, without risking a loss of balance.…”