Here is a very interesting article on hearing voices. It delves into the idea of ‘normals’ who hear voices and normals and mentions schizophrenia. I have posted a few excerpts that were relevant and interesting:
“There’s an increasingly popular theory on how our brain makes sense of the world. Rather than just receiving sensory information passively, our brain is actively making predictions about the world and looking for meaningful patterns,”
The theory called predictive processing or predictive coding posits that a lot of our experience of the outside world is more about what we expect we happen rather than what is actually happening. It may explain, for example, why we tend to see shapes in clouds and Rorschach blots. We experience what we expect to experience, and we only change those predictions or expectations once we have enough evidence forcing our hand.
That study exposed hearers, non-hearers, and schizophrenics to a stimulus known to trigger auditory hallucinations. The stimulus presents a person with a sometimes hard to hear tone and a light at the same time. Over time, upon each appearance of light, people have a tendency to say they hear a tone even though there isn’t one.
This tendency, to hear the tone when none was present, was especially likely to happen to those who hear voices – whether or not they had psychosis. Again, suggesting that voice hearers are primed to hear sounds in their environment. The biggest difference between those who heard voices and those who heard voices and had psychosis was their ability to accept that the tone wasn’t real. Non-psychotic voice hearers accepted that it was happening in their heads, which again leads credence to predictive processing theory—our expectations really might matter.