William,. "Crystal meth" is a highly addictive, cheaply and easily made substance that has been popular with drug abusers for years. The ease of manufacturing has resulted in many crystal meth houses, or "kitchens'' where the drug is "cooked," and dealt (ie,sold), as well as used. I don't know the specific action of crystal meth on the brain but I'm sure it's not good. Marty Polonsky