circadian alignment evening types late chronotypes
Conditions
Interventions
None listed
Sponsors
Philips Consumer Lifestyle
Eligibility
Age
18 Years to 99 Years
Inclusion criteria
Inclusion criteria: Healthy men and women between ages 20 and 30 y with a median to late sleep phase.
Exclusion criteria
Exclusion criteria: • Two time zones transmeridian flights (or more) one month prior to participation • Regularly taking naps (on average more then 2 per week) • Shift work during the last 3 months • Colour blindness • Visually impaired • Ophthalmologic complaints or a history of eye surgery • Somatic and psychiatric diseases (depressed mood rating BDI-II-NL >8 • History of chronic diseases • Excessive daily amount of caffeinated drinks • Alcohol or drug problems • Regular medication 3 months prior to participation • Smokers • Habitual midsleep later then 6:07 (>5% extreme late chronotype)
Design outcomes
Primary
| Measure | Time frame |
|---|---|
| Main study parameter is the rhythm of melatonin concentration in saliva. A shift in phase markers of the melatonin rhythm is interpreted as a shift of the endogenous circadian pacemaker. | — |
Secondary
| Measure | Time frame |
|---|---|
| (1) Ambulatory rest-activity rhythms (2) Subjective ratings, e.g. sleepiness, headache, chronotype | — |
Countries
Netherlands
Outcome results
None listed