Haptic information provided by anchors and the presence of cognitive tasks contribute separately to reducing postural sway in young adults

Abstract

BackgroundHaptic information provided by the anchors reduces postural sway while standing upright. It is unclear whether this benefit would remain in the presence of cognitive tasks combined with a more challenging postural task. Research questionOur aim was to investigate the effects of the anchors and visual and auditory cognitive tasks on postural control in young adults in a challenging balancing task. MethodsTwenty young adults stood upright on a balance beam with the central portion of each foot placed over the beam and feet at shoulder width without and with the use of the anchors in three cognitive conditions: control, visual Stroop task, and auditory digit-monitoring task. Each anchor consisted of a flexible cable with a light load (125 g) attached at one end of the cable. With the anchors, the participants held the flexible cable in each hand with the light load resting on the ground while keeping tension in the cable. ResultsBoth visual and auditory cognitive tasks reduced the center of pressure (COP) ellipse area, the root mean square of the margin of dynamic stability (based on the extrapolated center of mass, COM) and increased the COM time-to-contact relative to the boundaries of the base of support in the AP direction. The anchors reduced the COP ellipse area. SignificanceThere is a functional integration between postural control and cognitive tasks, such that postural sway was reduced to facilitate the execution of the cognitive tasks. Anchors were effective in reducing postural sway, suggesting that haptic information was able to benefit postural control in a challenging balancing task regardless of the cognitive task.