The Effects of Red and Blue Lights on Circadian Variations in Cortisol, Alpha Amylase, and Melatonin
Figure 3
Lighting condition measurements. Mean normalized concentration levels of melatonin (a), cortisol (b), and alpha amylase (c) collected during the day (09:00, 13:00, and 17:00) and during the night (21:00, 01:00, and 05:00) following one hour exposures of 40 lx of narrowband red (R) and blue (B) lights while subjects were continuously awake for one day, together with mean normalized concentration levels collected at the same clock times under constant dark (D) conditions.
