Schizophrenia, as I talked about earlier, is clasically a disease of delusions and hallucinations, often auditory (hearing voices). Some interesting data was brought up yesterday in class, and it goes something like this (I don’t have the reference, sorry):
When you or I want to say something, there’s an excitatory signal sent to the nerves that control our mouths and tongues so we can say the words properly. But there’s also an inhibitory signal that goes to the temporal lobes, when auditory information is processed. However, if you only listen to yourself say the words (from a tape recorder, for example), you don’t get that inhibitory signal in your temporal lobes. Researchers believe this is a way the brain tells the difference between sounds originating from the inside and the outside.
And, as you might expect (or else I wouldn’t be posting this), schizophrenics seem to lack that inhibitory signal when they themselves speak. The theory then goes that perhaps schizophrenics can’t tell the difference between thoughts or signals from inside their heads and outside, causing them to hear voices “from outside” that are saying things.