REM ans activity is present but why in night terror there is inc. ans activity seen and not in night mares?

REM ans activity is present but why in night terror there is inc. ans activity seen and not in night mares??

Nice Q. The neurochemical changes during different phases of sleep in the influence the autonomic system. Hence, in REM phase one of the important transmitters released in acetylcholine and acts like antidote for the arousal effect…

ok…any other Neurotransmitter changes which can occur in sleep??

Please give in detail