This episode investigates whether transcranial bright light treatment improves psychomotor speed in professional ice hockey players. Researchers conducted a double-blind, placebo-controlled trial exposing one group to bright light and a control group to sham treatment for 24 days. Results showed a significant improvement in motor time (but not reaction time) with visual cues in the bright light group. The findings suggest a potential non-visual pathway for light's impact on brain function, possibly involving opsins. The study's limitations include a small sample size, and the potential influence of learning or placebo effects.