The way I look at all this: The brain (or mind) is a kind of pattern amplifier. It is designed to take raw sense impressions of all kinds and adds an interpretation to it that is partly from what is there, partly from past experience, and partly from pure imagination. Piaget calls it Assimilation and Accomodation.

Our "perceptron" is usually tuned to a point very close to where feedback can happen. This is similar to what happens when you turn an amp up too high, the mic hears the speakers, and there is a loud squeal.

Schizophrenics suffers from the preceptron gain being turned too high.

Very imaginative (artistic and intelligent) people have their perceptron gain tuned on the high end. People like Einstein or Dali. Dali was actually partially in feedback, he was slightly crazy. Einstein had a son who was crazy. People with "psychic" abilities are actually tuned high but somewhere in the normal range. There is really nothing unusual about seeing things or hearing voices. Everyone does if they have a shred of ability for self-reflection. When the gain on the perceptron is set low, a very common condition, people cannot even understand what it means to have an imagination, have little artistic talent, diminshed intellects, poor in math, and tend to be very conformist. They are unable to understand other who are unlike themselves.