The connection between language, handedness and schizophrenia is fascinating. The cardinal symptoms of schizophrenia - auditory hallucinations, thought inserti

The connection between language, handedness and schizophrenia is fascinating. The cardinal symptoms of schizophrenia - auditory hallucinations, thought insertion (believing someone is inserting thoughts into your head) and thought broadcasting (believing that people can hear your thoughts), can all be regarded as a problem assigning the source of your thoughts. I.E. if someone tells you something, and you process this as a thought, if you lose the 'metadata' of the thought, you might be unsure if this originated from yourself or someone else. Handedness came about with the development of language - for most people (even left-handed), the language centre is on the left side of the brain. Lack of handedness is associated with increased risk of schizophrenia. There's a professor who used to teach me at Oxford who believed that the genes involved with handedness and brain lateralisation are the same genes involved in schizophrenia.