The influence of ambient lighting levels on postural sway in healthy children

The purpose of this study was to determine whether postural sway in healthy children varied in different levels of ambient lighting. Twelve boys and 26 girls with a mean age of 118 months stood on a force platform under three conditions: eyes closed, eyes opened in regular light (200 lx) and eyes opened in dim light (3 lx). Analysis of variance and pairwise comparisons revealed significantly more postural sway with the eyes closed condition compared to the regular and dim light conditions but no differences between the regular and dim light conditions. While our results on postural sway during the eyes closed condition are consistent with current findings in the pediatric and adult literature, our findings comparing postural sway during regular and dim light conditions differ from those found in older adults. It appears that the visual system of children is efficient in dim light conditions, adding support to the view that quiet standing is more dependent on vision in older adults than in younger individuals.