Fig. 4.

Effects of noninvasive tDCS on standing postural sway complexity. Postural sway was recorded under single-task (i.e., standing quietly with eyes open) and dual-task (i.e., eye-open standing while completing a non-postural cognitive task) conditions, immediately before and after real or sham tDCS targeting the left prefrontal cortex. tDCS did not alter sway complexity in the single-task condition (a). When compared with sham tDCS, real tDCS resulted in a significant improvement in Ci when standing with performing a cognitive task (i.e., dual task) (b) and the percentage change of complexity from normal to dual task was reduced significantly as compared to sham condition (c). *Significant interaction (p < 0.05) between tDCS condition (real, sham) and time (pre-tDCS, post-tDCS). Error bars represent 1 SE from the mean