Sometimes when I smoke a lot of weed I feel kind of psychotic. My thoughts get disorganized and there is a depersonalization effect. When I cut back to like one or two smoking sessions a day I feel more alive and connected to the world.
Like someone said earlier cutting back on things like caffeine and eating heathier help to detox your liver and to clear your mind. Colon detox is a good thing to try if you are a heavy user.