Effects of Afternoon and Evening Light on Teenagers' Melatonin Levels, Alertness, Sleepiness and Sleep

Launched by UNIVERSITY PSYCHIATRIC CLINICS BASEL · Jul 31, 2022

Keywords

ClinConnect Summary

Light exposure during adolescence seems to be the critical component of a vicious circle. Due to the maturation of sleep-wake regulatory systems in combination with progressively ill-timed exposure to light and early school start times, teenagers suffer from the accumulation of sleep depth during school days. Therefore, the proposed study investigates whether the physiological and alerting effects of late evening light exposure in adolescents depend on the intensity of light exposure in the preceding afternoon (primary endpoint: evening melatonin concentration).

The investigators aim to de...

Gender

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Eligibility criteria

• Inclusion Criteria:
• • Healthy
• • Capable of judgment
• • Normal BMI (Age-related Body-Mass-Index Percentile \> P3 \& \< P97; approx. corresponding to 28.5 ≥ BMI ≤ 16)
• • Signed consent form of participants
• • Signed consent form of a legal representative
• Exclusion Criteria:
• • Pregnancy or breastfeeding (only female)
• • Current participation in other clinical trials
• • Extreme chronotype (Extreme early or late chronotype/mid sleep time: mid-sleep time \< 1:00 / \> 7:00)
• • Extremely short or long sleep durations during school- or work days (\< 6 hours \> 11 hours)
• • Sleep disorders
• • High myopia (\< -6 diopters)
• • High hyperopia (\> +6 diopters)
• • Non-normal best-corrected visual acuity (BCVA \< 0.5 \[20/40\])
• • General health concerns or disorders, including heart and cardiovascular, neurological, nephrological, endocrinological, and psychiatric conditions
• • Ophthalmological or optometric conditions
• • Medication impacting visual, neuroendocrine, sleep, and circadian physiology
• • Drug and alcohol use (urinary drug screening \& breathalyzer test)
• • Non-compliance with sleep-wake times: \>1 deviation from ±60 minute window sleep and wake-up time
• • Non-compliance with caffeine intake (\> 1 times caffeine intake)
• • Transmeridian travel (\>2 time zones) \<1 month prior to the first session of the study
• • shift work \<3 months prior to the beginning of the study