Are you of those people who wake up at dawn, sufficiently energized to run a marathon, but who have to find the arms of Morpheus as soon as the sun has disappeared? Or those who can write a whole thesis when night envelops them, but who struggle to open their eyes when the alarm rings?
In a society where the future belongs to those who get up earlybeing night owl is sometimes frowned upon. We accuse the knock of discipline or of being lazy. On the other side of the pole, you can criticize the uptime because they are unable to watch late.
However, in one case as in the other, the lack of will has nothing to do with it, it is rather physiological differences. Because our tendency to get up sooner or later is dictated by our biology, more precisely by our chronotype.
And at the dawn of this new school year, knowing the ins and outs can be a success factor.
A concept deeply rooted in biology
Julie Carrier
Credit: Amélie Philibert, University of Montreal
The chronotype is the individual expression of our internal biological clock, indicates Julie Carrier, professor in the Psychology Department of the University of Montreal and researcher at the Center for Advanced Studies in Sleep Medicine of the Sacred-Coeur-de-Montréal hospital.
On the one hand, we describe as “morning birds” the people active at dawn, but tired in the evening and, on the other, “night birds” those that work better when everyone sleeps.
Chronotypes are not just a personal preference, they would notably be influenced by the secretion of melatonin – the hormone which facilitates falling asleep by signaling to the body that it is dark – and genetics. “Some genes associated with the circadian rhythm govern the time at which we naturally feel the desire to go to bed or that of getting up. This explains why some families have more or less birds in the morning or night, ”said the researcher.
Neuro-imagery studies have also shown differences in connectivity and cerebral structure between the uptake and the tard raises. This natural trend is also modulated by habits (such as exposure to screens in the evening), light signals of the environment and age.
“In general, children and elderly people tend to be more morning, while adolescents and young adults are more nocturnal. But our basic clock remains the same: a person who is noctambule at 20 will continue to go to bed late even at 70, simply a little less late than before, ”says the professor.
The challenges of “social gap”
Julie Carrier specifies: most individuals are somewhere between morning birds and those at night. However, some are at the extremes of the spectrum and they must adapt their internal clock to the usual school or professional hours.
“The challenge, especially for night birds, is therefore to find a balance between their biology and their obligations. In a world where courses start at 8:30 a.m. and where you have to get to work early, evening chronotypes often live a chronic sleep deprivation, which can harm their concentration, memory and productivity. In the long term, studies also show links with more depression, anxiety or consumption problems, even if causality is not yet clear, ”she underlines.
Conversely, the researcher continues, if the uptakers are forced to work late in the evening, they can see their vigilance and their performance decline.
“It’s a bit like left -handed: the usual requirements of their environment are not designed for their physiology,” illustrates Julie Carrier.
Despite everything, not inevitable
Although the chronotype is inscribed in our biology, it can be modulated, would like to recall the professor. “Even if it is true that life is a little less made for evening chronotypes, I want to send a message of hope that it is possible to adapt,” she says.
To get there, the researcher indicates that light is the most powerful signal to adjust our clock. Exposing themselves to natural light in the morning helps night birds advance their rhythm, while evening exhibition allows the uptake-up to repel sleep. Conversely, reducing exposure to screws and lively lights in the evening promotes a bed earlier.
She adds that certain behaviors can also help nightclubs, including avoiding stimulants at the end of the day, establishing a regular sleep routine and, if necessary, take a nap to recover the missing hours. These strategies do not transform an inveterate-tardente-tarden into a time, but they reduce the gap with the schedules imposed.
“My big wish, summarizes Julie Carrier is that students can preserve a quality sleep, from seven to nine o’clock per night, to meet their university and adaptation challenges.”
