Does early school time disrupt UAE students' natural sleep-wake cycle?

Developmental changes in sleep and circadian processes have important implications for learning, memory and emotion.

The circadian rhythm is the body's way of regulating the human wakefulness and sleep cycle. When this system is working well, that is when wakefulness occurs at times that are appropriate to our internal biological times, we function well.
When the circadian rhythm is disrupted and wakefulness occurs at inappropriate biological times, many areas of functioning are impaired. An obvious example of this is jet lag. Many of us can relate to the impact this disruption to the circadian rhythm has on mood, concentration and performance, to name a few.
This biological system of wakefulness and sleep regulation differs across the lifespan. Developmental changes in sleep and circadian processes have important implications for learning, memory and emotion. There is a large body of scientific literature which suggests that the current trend of early school start time causes a disruption to the natural sleep wake cycle of young and mature adolescents, with far reaching consequences. The effects are twofold. Firstly, the direct association between circadian misalignment and mood and cognitive functioning are observed. Secondly, as a secondary outcome of long-term circadian misalignment, the effects of chronic sleep loss are noted also.
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Research conducted in the U.S. comparing early and late start times in adolescents notes that later school start times are associated with a significant improvement in academic performance, mood, attendance and concentration. Increase in overall sleep time has been reported, while daytime sleepiness decreased, intake of caffeine decreased and motor vehicle accidents were significantly reduced.
Interestingly, the change in start times need not be that dramatic to see these changes. The studies included in the research cited 25- 60 minute later start times.
This supports another finding which suggests that in the current early school start time system, students are significantly less productive in the first lesson of the day. Educators wanting to play to students' strengths might consider scheduling first thing those lessons that require less high level cognitive functioning.
The majority of research into school start times has been conducted with adolescents. When considering whether to move school start times, policy makers need to apply these findings to high school age students. The different circadian rhythm of younger children may well point to a retention of the current start times for those children.