Acetylcholine increases noise relative to signal in brain circuits during REM sleep, contributing to fuzzy logic during dreaming.

“during REM sleep levels of neur adrenaline are at Flor levels neur adrenaline is shut off one of the things if you sort of drop neur adrenaline onto neural Circ it will very much increase what we call the signal to noise and this is why noradrenaline when it's released or if you administer it to an animal you can become very you can become almost um more directed you're much more Divergent you're focused in attending and it's really there you're very blinkered you're very focused but when that goes away the neural circuits become a little bit more Loosey Goosey”