Schizophrenia is a chronic, severe, and disabling psychosis, which is an impairment of thinking in which the interpretation of reality is abnormal. Psychosis is a symptom of a disordered brain. Approximately 1 percent of the population world-wide develops schizophrenia during their lifetime. Although schizophrenia affects men and women with equal frequency, the disorder often appears earlier in men, usually in the late teens or early twenties, than in women, who are generally affected in the twenties to early thirties. People with schizophrenia often suffer symptoms such as hearing internal voices not heard by others, or believing that other people are reading their minds, controlling their thoughts, or plotting to harm them. The current evidence concerning the causes of schizophrenia is a mosaic. It is quite clear that multiple factors are involved. These include changes in the chemistry of the brain, changes in the structure of the brain, and genetic factors. Viral infections and...