What causes grogginess when you first wake up – what about your brain isn’t working?

Question

What causes grogginess when you first wake up – what about your brain isn’t working?

In: 956

Answer 1

Your sleep is made of two different flavors: the “rest your brain” one and the “reorganize your brain” one. You get woken up in the first one, not good. You get woken up in the second one, good. Each night you cycle over multiple “rest your brain” and “reorganize your brain” phases.