Circadian rhythms

Definition of circadian rhythms

Chronobiology is a branch of biology which studies circadian rhythms, that is to say the biological rhythms which fluctuate over a cycle of 24 hours.

The two types of circadian rhythms:

  • Physiological rhythms: wake-sleep pattern, body temperature, etc.
  • Biological rhythms: melatonin, cortisol, growth hormones.

These different rhythms are all synchronized together and are controlled by our biological clock, located in the superchiasmatic nucleus, themselves housed in the hypothalamus within our brain.

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.

Discover what role light plays on the body

with Roland Pec - sleep specialist and chrono-therapist


The Luminette reproduces the beneficial effects of the sun and stimulates specific receptors, located in the eyes, which activate the energizing response that light has on the body. It will help you to fight against slumps in energy, allowing you to feel more in shape and it will have a regulatory effect on your sleep patterns.

What our customers say about Luminette