Nocturnal Habits: The Unbearable Lightness of Sleeping

He opened his eyelids, yawned, stretched his body awake and smiled. Waking up in a tent with the first rays of daylight and a symphony of birds was going to liberate him -- in a sort of survival camp way. But he wasn’t quite aware of what this journey would reveal. Not quite yet.


[A sweet distant voice shook gently his consciousness] “Do you listen to your body? (Pause for 3 seconds) Are you capable of slowing down or picking up the pace according to your energy supply levels? (Pause for another 3 seconds) Hey, Mr. Businessman. Hello. Do you copy me?” “Oh. Hi. Yes, sorry. I have no time for the ‘biological clock’ preaching. I have an urgent work task. Talk another time. Copy.”


As the days passed by, so did the challenges in an environment former Mr. Businessman was not familiar with. Sprinting during game hunting and picking berries and flowers were his favorite tasks despite the effort they required of him. Sharp focus, agility and body resilience were required to excel on those simple tasks. So, he trained assiduously, not only his body strength, but also his mind.


[The sweet voice comes back] “Let’s talk openly, Mr. Businessman. I do not think these one-to-one conscious check-ups have been helping you recover from an inner state of disorder. I was meant to guide you in your re-questioning of life choices. Perhaps now is time to pay a visit to Dr. Clock, the wellness counselor. Unless you would prefer to open the burn-out door. Do you copy me?” (No answer).


In the nature and without modern distractions, he was able to finally listen to his inner gentle whisperings, which are key for a long and sane survival.


[The voice faded into the background noise] The burn-out door was already open anyway. At this point, in order to take back his life in hands, Mr. Businessman had to listen carefully to Dr. Clock’s advice: “Everything starts with a quality night’s sleep. This fact is as true for growing children as it is for you,” said Dr. Clock. A good night’s sleep starts in the morning! It’s important to expose yourself to daylight as soon as you’re awake and go exercise outside as well. But be careful, bright light exposure is no longer a friend when evening knocks on the door. At this time, try to avoid bright light at least 2 hours before bedtime, including LED screens like the ones on your cell phone and computer. In fact, it’s better to put them away entirely. Choose some relaxing activities like reading or listening to music to slow down your body and leave your stress outside the bedroom,” added the counselor. “If we don’t see good results in couple of months, then I am afraid you will need a more intensive treatment.”


Most people do not take the time to listen to their bodies anymore. In fact, studies consistently show that two-thirds of the population feel tired throughout the day. Reduced cognitive ability, health impairment, increased irritability and anxiety are few of the negative outcomes. A good night sleep is an accessible remedy, yet only for those with self-discipline. In my quest to aid people cope with the modern reality -- today’s overwhelming outdoor or indoor light pollution --or even the ubiquitous LED screens in our lives -- I studied the effect of light on human behaviour and sleep. Two main areas were explored:


(1) The effect of a dawn simulation light at wake time. It is a light that mimics the sunrise during the last 30 minutes of someone’s sleep (before the alarm clock actually runs off). We discovered that people waking up with that light felt less sleepy, had a higher state of well-being during the day; and obtained better day performance. In addition, the heart rate at the sleep/wake transition was less abrupt, thus lessening the risk of falls and/or cardiovascular events in the morning.


(2) Long-term light exposure in young and older participants. We kept our participants awake for 40 hours and exposed them either to a dim light, a normal white light or a blue–enriched white light. We could observe that the participants reacted differently depending on which light they were exposed to. Additionally, the older subjects reacted differently to the same light when compared to the young counterparts. Bottom line: As we age, physiological changes in our retina and our brain occurs, leading to a weaker light signal transmitted to our internal clock, located in the brain. As a result, our body will then find it be more difficult to adapt to the 24h light/dark cycle. This can result in increased nocturnal awakenings and diurnal naps.


Drinking several cups of coffee throughout the day to keep you going? Perhaps it is time to become mindful about your biological clock. I’d be happy to help you adjust your daily activities in order to improve your sleep quality. Don’t hesitate to contact me at Clock&Me. Sleep tight!


I am Virginie Gabel and the above topic was my PhD research for the team headed by Prof. Christian Cajochen at the Center of Chronobiology (Psychiatric University Clinics in Basel, Switzerland). The research was funded by several partners including Philips (the Netherlands), Velux and AXA (Switzerland).


Text by Fernanda Haffner

Illustration by Marion Couturier