In my single personal anecdote, it was very different from sleep, but in a way that is hard to articulate. When I’m asleep, there’s still a “me” of sorts. I dream some, I drift to varying levels of consciousness, maybe get closer to awake and turn over, and so on.
The one time I was put under, it was like a switch got flipped somewhere and I was just put on pause. One moment I was there and they were having me count backwards and literally the next moment they were talking to me as they brought me out. I opened my eyes and they’re putting instruments away and cleaning up. No sensation of passing time at all. It was like a time-slip. A blink and it’s a couple hours later.
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