Circadian rhythms

The biological clock is based on three synchronizers :

Melatonin, also called the “sleep hormone”, which is secreted by
the pituitary gland (which gives information about the alternation of
day/night) and “resets” the body with its environment.

 

Light (alternation night/day) if it is received by the eye
receptors in a sufficient quantity and if it is made up of good wave
lengths (blue light)

 

Lastly, social factors (family life, leisure, sports, etc.) also serve as synchronizers.



The main circadian rhythm is the alternation of wake/sleep but other
rhythms exist which vary from day to day : body temperature, our
cortisol level, melatonin secretion, etc...



The body also searches for a temporal balance between itself and the
outside world. When our internal clock is no longer synchronized with
the actual time, a pathological situation follows, of which the
principal symptoms are trouble sleeping, waking up and temperament.