system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5: Why can we never tell the exact moment we fall asleep?

This concept has always baffled me.
Any help understanding this would be greatly appreciated!
gpt
This is because your body goes through a series of transitions as you start falling asleep. Muscles relax to the point where you should be unable to move them at one point, breathing slows, body temperature decreases and your brain goes through some transitions as well. Changes are, amongst others, how we process memory and thoughts.

For you to remember the act of falling asleep, you would need to tell your brain to help you retain full consciousness til the very last second, only then would you be able to perceive the change of consciousness itself, but since it is a process, your ability to remember you falling asleep to the second is, unfortunately impossible.