Expressionism

I find this interesting. An artist on Acid.
Check this. Now check, for instance, Kandinsky, Campendonck, Braque.
So were all Expressionists (and other modernists) on drugs? Or did they attain a state of mind that was similar to a drug-induced high, due to some other influence (talent?)? I think it's most fascinating. Then again I'm a bit strange, me.