Buzzzzzzzzz! Is it morning already? “How is that possible?” you wonder as your fingers fumble for the snooze button. Hitting the switch, you tell yourself: “Just five . . . more . . . minutes”.
If you find it difficult to wake up to the artificial, pre-set time on your alarm every morning, you are not alone. Day in and day out, humans force themselves out of natural sleep with the unnatural clanging, buzzing or ringing of alarms.
And so it goes. Once the fog of sleep has cleared, most people are able to get started with their days and find the energy for work, study, sport, childcare, etc. But what happens to so many of us later in the day? After the lunch hour—somewhere around 2:00 pm—many people feel sleepy. Is it the result of not getting enough sleep the night before? Is it caused by eating too heavy a lunch? Possibly.
More often, however, that afternoon drowsy feeling is the result of the human circadian rhythm kicking in—a natural reminder that humans cannot necessarily control everything about themselves. “Our built-in 24-hour clock . . . imposes a regular pattern of wakefulness and sleepiness over the course of the day,” wrote John Cline, Ph.D., in his 2016 article for PsychologyToday.com. “The circadian rhythm supports alertness in the morning, . . . and allows drowsiness as the sky grows darker.”
Cline further explained that in the afternoon, the human circadian rhythm reaches a low point of alertness, gradually rising again until the early evening when we begin to feel sleepy for day’s end.
While most of us yearn to yield to the ebb and flow of our daily rhythmic need for sleep, only a small percentage of humans take that afternoon nap. Obligations of work, school, and family make a refresher of our biological clock only seem to happen on days off, on holidays, or when our body gives in to a cold or the flu, and demands sleep.
“The siesta is the most well [-known] acknowledgment of the usefulness of an afternoon nap,” Cline wrote. “It can help restore alertness and mental effectiveness without interfering with the ability to fall asleep at night.”
Overriding the natural human ‘clock’, or circadian rhythm, is nothing new. In 1882, after inventor Thomas Edison created a long-lasting incandescent lightbulb, outdoor street lighting and indoor lights allowed humans to have more control over their sleep times.
Researchers have long studied the physiological effects on humans who systematically reject their circadian rhythm—for shift or night work, for example. Some findings include loss of productivity and an increase in on-the-job mistakes. But, what are the psychological effects that result from rejecting the natural need to sleep? Recent studies show how our mental health suffers.
According to Annaëlle Charrier et al, in their study of “. . . Altered Sleep-Wake Rhythms: Their Role in the Development of Psychiatric Disorders”, their findings indicate “Impaired circadian rhythms . . . might lead to anxiety and . . . some psychiatric disorders . . . such as ASD [Autism Spectrum Disorder], schizophrenia and anxiety disorder.”
In the last two years, recognition of the mutually dependent relationship between interrupted circadian rhythm/the need for sleep and the consequence of mental health illnesses has come to the forefront of research, culminating in the October awarding of the 2017 Nobel Prize in Physiology or Medicine to the communal work of American scientists Jeffrey C. Hall, Michael Rosbash, and Michael W. Young for their discovery of the molecular mechanisms controlling human circadian rhythm.
According to a press release published on nobelprize.org, the trio proved that “With exquisite precision, our inner clock adapts our physiology to the dramatically different phases of the day”.
Moreover, their work provided “. . . indications that chronic misalignment between our lifestyle and the rhythm dictated by our inner timekeeper is associated with increased risk for various diseases”, including mental illnesses.
Likewise, the results of a three-year study at McLean's Translational Neuroscience Laboratory in Belmont, MA, provided similar indications of the interdependence of irregular circadian rhythms and their detrimental effects on mental health.
In a 2016 article for Science Daily, Harry Pantazopoulos, PhD, assistant neuroscientist at McLean's and instructor in psychiatry at Harvard Medical School, said that for the 50 years prior to these studies, evidence showed something amiss with the circadian rhythms in people with bipolar disorder. Until now, however, “there has been a huge gap in terms of what we understand about their brains and how altered circadian rhythms are contributing to their symptoms,” he wrote.
So what now? Should we stop using alarms to wake us in the morning? Not possible. Should we return to bygone times when we slept and rose with the sun? Not feasible.
In his June 2013 Ted Talk, Russell Foster, Professor of Circadian Neuroscience at the University of Oxford, summed up what may result from this research, saying it all raises “. . . the possibility that sleep and circadian rhythm disruption may be an important factor in the early diagnosis of individuals with mental illness. This is hugely important,” he said, “as early diagnosis offers the possibility of early help.”
Treating sleep problems and circadian disruption can only help to improve the lives of people living with mental illness. In the meantime, Foster added, humans will continue to use the lightbulb to “invade the night and occupy the dark”.
References
Charrier, A., Olliac, B., Roubertoux, P., & Tordjman, S., (April 29, 2017). International Journal of Molecular Sciences. Clock Genes and Altered Sleep–Wake Rhythms: Their Role in the Development of Psychiatric Disorders. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5454851/
Cline, J., Ph.D., (September 27, 2016). Psychology Today. Secrets of Napping. https://www.psychologytoday.com/blog/sleepless-in-america/201609/secrets-napping
Foster, R., (November 10, 2015). The Independent. How Understanding Disrupted Sleep Could Help. http://www.independent.co.uk/life-style/health-and-families/features/sleep-mental-health-circadian-rhythm-a6728086.html
NobelPrize.org., (October 2, 2017). Press Release: The Nobel Prize in Physiology or Medicine 2017. https://www.nobelprize.org/nobel_prizes/medicine/laureates/2017/press.html
Science Daily (May 31, 2016). sciencedaily.com. New findings linking abnormalities in circadian rhythms to neurochemical to changes in specific neurotransmitters https://www.sciencedaily.com/releases/2016/05/160531104032.htm
