

Good easy explanation. No disagreements here. Just going to tack on:
We also don’t know what consciousness is or how it happens. The drugs used to put you under (the general anesthesia) work under one of two paths. Block sensory information from being written to memory, or block the process of writing the memory. Some drugs do it one way, some drugs the other, some do a little of both. We know both methods are true, and both put people under.
This leads to one major theory, that your brain needs memory to have consciousness. We also have the theory (from observing this exact question) that it is easier for your brain to write to short term memory than long term. Now there is the issue, if the general anesthesia wears off or goes below threshold needed to write to short term, then the person is awake and starts to act funny due to impaired sensory information (think of all the funny anesthesia YouTube out there) but the person isn’t writing the memory to long term memory because there is still just enough in the system to block it. Which is why they can’t ever remember the funny things they said or did.
Now combined this with the paralytic from the above comment. If you start to cross the threshold of short term memory coming back online, and this is a major signal to the anesthesiologist to increase the dosage. But you have a paralytic, so they don’t know you are coming out of it. Then you drop below the threshold for long term memory and now the person truly has “woken up” back to consciousness and rightfully complain of the terrifying experience.



I missed you by 1 min. Read my addition to the other comment.