Quote Originally Posted by Ryene Astraelis View Post
@ machintruc: I already know their roles. Thanks, though. Norepinephrin is similar/somehow related to adrenaline, right?
Yes. Norepinephrin has a role in vigilance and concentration (as well as dopamin).

When too low, you can't concentrate on anything, and your thinking process is "deliberate".

When too high, you tend to concentrate or random and useless things, and your thinking process is "restless". You can't focus on adequate things.