It affects approximately one person in a hundred. It is not a split personality, which is a very rare and different disorder. Its onset is usually in the late teens or early twenties. Onset after age 30 is uncommon and rare after age 40. The symptoms of the illness usually begin gradually so that family may not understand what is happening as a person begins to become ill.
Schizophrenia is an illness that causes problems in thinking, feeling, and relating.
Since the brain is the most complex organ in the human body, it is not surprising that things can go wrong with it. In the 1950s researchers began to discover that illnesses such as Schizophrenia were biologically based. In more recent years, through the development of more precise imaging equipment such as CT, MRI, and PET scans, and the development of drug research, this discovery has become even more conclusive. Schizophrenia is a brain disorder. Although the cause of Schizophrenia is still not completely understood, it is believed that the functioning of the brain's neurotransmitter is involved.