Insomnia

Sleep is essentially driven by the circadian rhythm (24 hours) :

· Slow and deep sleep predominates in the first half of the night, whereas paradoxical/REM sleep occurs more in the second part of the night.
· In addition, sleep induction latency periods are cyclical. They depend on the time that the subject goes to bed. At 8 p.m., the wakeful period before falling asleep may exceed 50 minutes in a young person, whereas at 7 a.m., it may take less than 5 minutes for the same subject to fall asleep.
· Sleep duration also depends on the time at which one goes to sleep. It may exceed 9 hours if one goes to bed at 8 p.m., and will be shorter if one goes to bed at 7 a.m.


However, the waking/sleeping cycle also depends on homeostatic regulation (this designates the organism’s tendency to maintain constant biological parameters in the face of external change).

To take an example, after a sleepless night, the period that the subject will sleep on the following night will only be extended 10 to 12 hours. There is therefore a build up factor that takes into account “sleep debt”, or the amount of sleep that has to be caught up.

According to Dr Borderly’s model (at the beginning of the 80s), it is serotonin that responds to homeostatic factors, and melatonin that responds to circadian factors. Melatonin is produced in the epiphysis, using serotonin. Melatonin has a sleep inducing effect, as well as a hyperthermia inducing effect (i.e. it reduces body temperature).

Sleep disorders can be interpreted as a dysfunction of our biological clock.
« Phototherapy is considered to be the best non-drug treatment against insomnia ».

For people who go to sleep early and wake up early :

Recommended dosage : 1/2 hour of light therapy using the light box, in the evening (around 5 p.m.).

For people who go to sleep late and wake up late :

Recommended dosage : 1/2 hour of light therapy using the light box, in the morning (upon waking).

For an in-depth solution, correct your sleep patterns and gain 15 minutes every 3 days.
For example, you go to sleep at 3 a.m. and wake up at 11 a.m :
From day 1 to day 3 : light therapy ½ hour in the morning at 11 a.m.
From day 4 to day 6 : light therapy ½ hour in the morning at 10:45 a.m.
From day 7 to day 9: light therapy ½ hour in the morning at 10:30 a.m...