High-Level Overview:
This study provides evidence for a circuit in the eye that is specifically looking for changes in blue content in our ambient environment. Since blue light content changes are most significant during twilight (sunrise and sunset), this provides evidence that we have a heightened sensitivity for these twilight events that bound our day and night.
What You Need To Know:
Circadian lighting is about brighter days and darker nights. However, this study shows that this is a significant impact of twilight as well. When possible, try to incorporate an element of twilight (sunrise and sunset) into your designs. This is a combination of blue sky getting bluer/purple and white sun getting yellower/redder.
Read The Study
A Color Vision Circuit for Non-Image-Forming Vision in the Primate Retina