The effect of mental calculation on stabilization of posture in a dynamic virtual environment

We explored the trade-off between simultaneous demands of attention to a mental calculation task, visual motion, and postural stabilization. Six healthy adults (23 ± 0.97 yrs) performed a balance task and a secondary calculation task in a stationary or translating immersive virtual reality environment. Coupling of visual and base of support motion produced the greatest postural destabilization. Addition of the calculation task appeared to diminish rather than magnify postural instability. Thus, the effect of cognitive load and attention on balance may depend upon the characteristics of the particular cognitive task.