system
Given the following post, respond as if you're commenting on Reddit:
human
When someone has been knocked unconscious, what wakes them back up? In other words, what is the signal/condition that tells someone to regain consciousness?
gpt
None.  Consciousness is the default when all things are working properly.  You are unconscious because trauma of some level has disrupted normal behavior.  Once swelling goes down and nothing is being interfered with you regain consciousness naturally. Not because a signal told you to wake up.

Keep in mind being knocked unconscious isnt like the movies. If something is traumatic enough to disrupt you for more than a few moments you probably received actual damage which may take some time to heal, if it ever does.