We have seen that chronobiology studies circadian rhythms and that the alternation between day/night is one of the most important synchronizers of our biological clock. When night falls, the drop in light marks the start of the sleep phase and the body (through the superchiasmatic nucleus) begins to secrete melatonin, inviting us to sleep. On the other hand, when day breaks, the increase in light marks the start of the awake phase. The body stops the secretion of melatonin and activates the secretion of the awake hormones (cortisol, serotonin).
As well as its regulatory effect on our biological rhythms, it is now proved that light equally has a physiological effect on the body. A recent study has indeed proved that light, if delivered in sufficient intensity and quality, improves mood and increases cognitive performances such as memory, vigilance, reactivity, intellectual abilities, etc.

Discover what role light plays on the body
with Roland Pec - sleep specialist and chrono-therapist