Schizophrenia is a very serious mental illness that changes the sufferer's thinking process and behavior. It prompts them to behave in anti-social ways and in the most extreme cases to commit violent criminal acts.
Usually, symptoms of this illness first appear in the late teenage years but it also sometimes affects children. In general, observers note that schizophrenic people become detached from the real world around them. They imagine they are in all kinds of strange situations and start to view what is going on around them from a very peculiar angle. Sometimes they become much less communicative and lose interest in their daily activities. This illness frequently reduces their attention span and impairs the functioning of their memory.
Despite years of research, there is still lots of debate over what causes schizophrenia. As far as we can tell genetic factors make certain people more likely to develop this mental illness. It also seems as though there is an environmental element in certain cases, for example, if certain problems occurred at the time of birth.