Belgium – researchers of the university of Liege affirm that the people who rise late remain alert longer than those who rise early. They also suffer less from fatigue than those who wake up early.

According to the hour of raising, the brain does not react in the same way during the day. The difference would be all the more obvious in end-of-day between early riser and late riser. The researchers monitored the sleep of sixteen people who go to bed and get up late and fifteen people who go to bed and get up early.

For two nights, they slept in the laboratory where their brain activity were monitored by MRI. Their rate of rise and sleep has not been changed, but the researchers asked them to perform their regular works which requires attention.

After 1:30 of awakening, all participants had the same level of performance and brain activity, as indicated by Passport Health. But after 10:30, the early risers had a notable fall of cerebral activity compared to the late risers. The early risers would have more trouble to leave the sleep.

The researchers explain that the awakening is related to two phenomena. The homeostatic process, either the desire of sleep in the course of day, and the circadian rate/rhythm, or junction points between sleep and awakening, when the body asks for sleep or awakening. The opposition of these two mechanisms would drive the levels of concentration and attention throughout the day.