The Alerting Effects of Caffeine, Bright Light, and Face Washing After a Short Nap
Summary
Combining caffeine, bright light, or face washing after a short nap enhanced alertness vs nap alone in mid‑afternoon sleepiness.
Why It Matters For Night Shift Workers and Night Owls
A crossover RCT how timing and spectrum of light on shift versus before daytime sleep found sleep & alertness for night‑shift workers and night owls. Together with other trials, it frames light as a measurable lever for on‑shift alertness and next‑day sleep, not just ambience. For people who work nights, that frames an everyday choice (when you eat, how you light the end of a shift, how rest is split) as part of the mechanism, not just routine.
Notes
Older but still‑cited lab study.