Quote Originally Posted by Robot_Butler View Post
I'm still a little confused, also about how you can dream in NREM sleep, not have any kind of physical paralysis/atonia, but still keep from acting it out?
Here you are assuming that any hallucinatory proprioceptive experience will necessarily lead to body movement, but that's an invalid assumption. For example, just as you could be hallucinate a pink elephant hovering in the air in front of you, you could hallucinate raising your arm, but that doesn't mean your arm has to actually move (or it wouldn't be a hallucination, would it?). The same holds true for hallucinatory experiences in sleep, also known as dreams. So it shouldn't be a mystery that you can have "inhabited" NREM dreams without acting them out.

So why then is atonia necessary to keep you from acting out your dreams in REM sleep? Well, bear in mind that the brain in REM sleep works in a very different way than in NREM sleep. It's probably safe to say that the difference between REM and NREM is as big as the difference between NREM and wakefulness. Just because atonia is necessary in REM sleep, there is nothing that implies that it's necessary in NREM sleep; the brain just works in a different way.