I believe it's a much more fundamental difference than just the distinction between ideating and acting.

Many people occasionally experience the transition between "conencted" and "disconnected" states as a sudden jerk or loud noise just at the moment of falling asleep.

Sleep paralysis is another "failure mode" of this mechanism that reveals what's going on. (I'm not sure if there is a reverse to it, i.e. whether sleepwalking could be explained as a drastic fail-open of the same mechanism).