As Aurelie Stephan, a sleep researcher from the University of Lausanne in Switzerland, explained, the brain doesn’t switch instantly from sleep to wakefulness. She referenced studies indicating that subcortical areas of the brain are responsible for our awakening. This group of neural structures lies beneath the cerebral cortex, as noted by Live Science. The reticular activating system (RAS) initially acts as a starter, sending signals to activate the thalamus, which relays sensory information to other parts of the brain and then to the cerebral cortex—the outer layer of the brain.
Why do we act like sleepy flies in the morning?
After , our brain still needs time for its cognitive potential to fully awaken. This period, known as sleep inertia, can last anywhere from 15 to 30 minutes, and sometimes even an hour, according to Ms. Stephan. Scientists are still unsure why this morning grogginess occurs, but the timing of our awakening undoubtedly affects how we feel. One way to combat this state might be to ditch the . However, this isn’t a universal solution for those whose days are meticulously scheduled.
“When the brain wakes up naturally, it sends a signal at the right moment. There are numerous areas of the brain that consider internal and external signals and communicate with each other about when to transition through different stages of sleep, and ultimately, when to spontaneously wake you up,” the expert explained.
Our awakening system listens to these internal and external signals, creating cycles in which we become more alert approximately every 50 seconds. Our level of alertness fluctuates within these 50 seconds, rising and falling repeatedly.
“During the rising phase, it’s harder to wake up. But when the cycle is on the decline, our sleep becomes more fragile, making it easier to wake up,” Ms. Stephan said. According to her, during these 50 seconds, we experience a period of continuous sleep and a period of its fragility. This is why the researcher advises her friends to always wake up at the same time. Importantly, without the help of an alarm clock.
“Your brain will wait for the right moment for 50 seconds, and you’ll feel less sleepy upon waking. If you set an alarm, it might wake you up at an inappropriate moment, leading to significant sleep inertia,” she explained.
However, despite everything we know about it, our awakening remains a mystery. For instance, scientists still don’t fully understand why the same amount of sleep one day can leave you feeling , while the next day it’s insufficient. Some researchers insist that morning alertness (that is, how the brain switches from wakefulness to sleep) is influenced by diet and sleep duration.
Photo: Openverse