I was meditating today and thought about my thoughts and realized that I never freak out completely after a thought has gone and imagined it in my mind like something peaking, going down and being lifted back up again.. A wave.. A brain wave!

Delta brain waves (0.5-4Hz) - Downers
Theta brain waves (4-8Hz) - Psychedelics
Alpha brain waves (8-12Hz) - Weed
Beta brain waves (12-35Hz) - Stimulants
Gamma brain waves (35Hz +) - Mania and epilepsy..