Why do we often wake up before the alarm clock rings?

Posted on Jan 12, 2021      200

Who of us has not woken up early in the morning and reliably did not look at the alarm clock: suddenly until the moment of rising there is still at least an hour? But as an evil thing to get up in a few minutes. It turns out that our body itself works as an alarm clock!

We are the owners of the most complex biological system, all processes of which are controlled by the brain. In one of its areas, the hypothalamus, there is the so-called suprachiasmotic nucleus, which regulates our biological clock - circadian rhythms.

Circadian rhythms are found in all living organisms on our planet. They control the intensity of various biological processes, such as hormone production. Most often circadian rhythms are tied to the change of day and night, but our body can also adjust to the daily routine, “memorizing” by its biological clock the moments when we get up and when we go to bed.

PER1 protein plays a major role in the sleep-wake cycle. When its level in the body drops, our heart rate slows down and our blood pressure and temperature levels drop. This is exactly what happens during sleep. Upon awakening, levels rise, “speeding up” the body’s biological processes - we feel more awake.

Unexpectedly, waking up for an alarm clock is always stressful for the body. To make it at least a little less stressful, the body adjusts the circadian rhythm of PER1 protein production to the time of the alarm clock. This is how our body tries to make the stress of waking up early less stressful for itself: while still asleep, the heart rate and blood pressure gradually increase and the hormones rise. Over time, the brain adjusts itself so precisely to the time of awakening that we open our eyes a few minutes before the alarm clock rings. Listen to yourself: in these moments we feel much more awake than if we woke up to the sound of the alarm clock.