Positive Effects of Blue Light on Postural Control and Motor Coordination in Older Adults: A Pilot Study

Abstract

Purpose: Falls are a risk factor for mortality in older adults. Light interventions can improve cognitive function and performance in motor tasks, but the potential impact on postural control with relevance to falling is unknown. This study aimed to examine the effect of light on postural control, motor coordination, and cognitive functioning. Methods: Sixteen older adults participated in an intervention study that involved four counter-balanced sessions with blue-enriched light delivered visually and/or transcranially for 12 minutes. Postural control in three conditions (60 s eyes open, dual-task, and eyes closed), lower extremity motor coordination, and cognitive function were assessed. Area of sway (AoS), coordination, and cognitive function were compared between the groups via repeated-measured ANOVA. Results: Relative to placebo, visual blue-enriched light exposure clearly decreased AoS (d = 0.68 ±0.73; p =0.166) and improved reaction time in the motor coordination task (d = 1.44 ±0.75; p =0.004); however, no signicant effect was seen on cognitive function. Conclusion Blue-enriched light demonstrates a novel clinical approach to positively impact on postural control and lower-limb motor coordination in older adults. By impacting on metrics associated with fall risk, blue-enriched light may provide a clinically meaningful countermeasure to decrease the human costs of falls.