Benefits and Risks of Artificial Light Exposure: Characterisation of Effects on Alertness, Sleep, Cognitive Performance, Mood and Biological Rhythms

• polychromatic light (Device): Application of polychromatic light at different times of day
• polychromatic light (Device): Application of polychromatic light for 2h30 at different times of day with sleep
• red light (Device): Application of red light at different times of day
• red light (Device): Application of red light at different times of day with sleep
• green light (Device): Application of green light at different times of day
• green light (Device): Application of green light at different times of day with sleep

Primary outcomes

• Cognitive performances assessed using N-back tasks [up to 56 hours]: N-Back-Task 1, 2, 3
• Cognitive performances assessed using Psychomotor Vigilance task (PVT) [up to 56 hours]: Psychomotor Vigilance task (PVT)
• Cognitive performances assessed using Paced Visual Serial Addition Task (PVSAT) [up to 56 hours]: Paced Visual Serial Addition Task (PVSAT)

Sex: All, ages: 18 Years to 40 Years, accepts healthy volunteers

Inclusion Criteria:

* Male or female
* Aged 18 to 40 years
* With a hint of Bodymass index (BMI) between 17 and 30 kg.m - 2
* healthy subject determined by a clinical examination, a psychological interview, a blood test, a urine analysis
* Subject with a score<6 questionnaire PSQI ("Sleep Questionnaire Pittsburgh")
* Subject agreeing to maintain a regular sleep/wake rhythm during the study
* Subject agreeing to refrain from caffeine, nicotine, alcohol, psychotropic drugs, cannabis or other drugs, during the study
* Signed informed consent
* Subjectaffiliated to a social protection scheme

Exclusion Criteria:

* somatic diseases: cardiovascular, respiratory, gastrointestinal, hematopoietic, Visual
* immune system diseases
* kidneys and urinary tract diseases
* endocrine and metabolic diseases
* neurological diseases
* infectious diseases
* thrombocytopenia or other malfunction of blood platelets
* Subject with risk of thrombosis, including subject with a history of phlebitis, smoker under oral contraceptive...
* Subject with an addiction to caffeine, nicotine, alcohol, psychotropic drugs, cannabis, or any other drug
* Subject treatment contraindicated or inadvisable in combination with heparin
* blood donation in the previous 3 months before the inclusion
* Participation in other clinical trials
* Work by shifts in the year preceding the inclusion
* Trans-meridian travel (> 2 time zones) in the month previous the inclusion
* Impossibility to give enlightened information (subject in an emergency situation, understanding difficulties,...)
* Subject under safeguard of justice
* Subject under tutorship or curatorship
* Pregnancy (women of childbearing age)
* Breastfeeding
* Diet incompatible with the study's snack choices

• Patrice BOURGIN, MD, Principal investigator, Hôpitaux Universitaires de Strasbourg