Mobile Technology Reveals Novel Insights into Human Sleep Behavior

Huge epidemiological studies to study human behavior are often very costly and time-consuming to conduct. However, researchers from the University of Michigan recently demonstrated that this does not have to be case by using a smart phone app called ENTRAIN to gather data on the effects of societal influences on current human sleeping habits around the globe and analyzing it with a mathematical model. The study revealed the length of one’s sleep is determined by bedtime rather than wake time. While bedtime and duration of sleep is greatly influenced by social pressures rather than biological drives, one’s wake time is more precisely controlled by one’s internal biological clock or circadian rhythm, which is controlled by a small cluster of cells behind the eyes called the suprachiasmatic nucleus. Sunlight exposure during the day can promote earlier bedtimes. Women tend to go to bed earlier and wake up later than men, who often sleep less than the minimum seven hours of sleep required to reduce risk of chronic diseases. Every half hour of sleep can translate to huge differences in brain function and long-term health. Age appears to be the primary factor in determining length of sleep as adults older than 55 have a narrowing window for falling and staying asleep. The CDC estimates about one in three people are sleep deprived. This work offers practical human-relevant insights for developing strategies to counteract the global trends of sleep deprivation while also demonstrating how mobile technology can make large human-based studies more cost-effective.