Schizophrenic disorders are severe conditions marked by disordered thoughts and com- munications, inappropriate emotions, and bizarre behavior that lasts for months or even years (E. Walker & Tessner, 2008). People with schizophrenia are out of touch with reality, which is to say that they are psychotic.
People with schizophrenia often suffer from hallucinations, false sensory perceptions that usually take the form of hearing voices that are not really there. (Visual, tactile, or olfactory hallucinations are more likely to indicate substance abuse or organic brain dam- age.) They also frequently have delusions—false beliefs about reality with no factual basis—that distort their relationships with their surroundings and with other people. Typ- ically, these delusions are paranoid: People with schizophrenia often believe that someone is out to harm them. Because their world is utterly different from reality, people with schizo- phrenia usually cannot live a normal life unless they are successfully treated with medica- tion. (See Chapter 13, “Therapies.”) Often, they are unable to communicate with others, since their words are incoherent when they speak.
Types of Schizophrenic Disorders Disorganized schizophrenia includes some of the more bizarre symptoms of schizophre- nia, such as giggling, grimacing, and frantic gesturing. People suffering from disorganized schizophrenia show a childish disregard for social conventions and may urinate or defecate at inappropriate times. They are active, but aimless, and they are often given to incoherent conversations.
In catatonic schizophrenia, motor activity is severely disturbed. People in this state may remain immobile, mute, and impassive. They may behave in a robotlike fashion when ordered to move, and they may even let doctors put their arms and legs into uncomfortable positions that they maintain for hours. At the opposite extreme, they may become exces- sively excited, talking and shouting continuously.
Paranoid schizophrenia is marked by extreme suspiciousness and complex delusions. People with paranoid schizophrenia may believe themselves to be Napoleon or the Virgin Mary, or they may insist that Russian spies with laser guns are constantly on their trail because they have learned some great secret. As they are less likely to be incoherent or to look or act “crazy,” these people can appear more “normal” than people with other schizo- phrenic disorders when their delusions are compatible with everyday life. They may, how- ever, become hostile or aggressive toward anyone who questions their thinking or delusions. Note that this disorder is far more severe than paranoid personality disorder, which does not involve bizarre delusions or loss of touch with reality.
Finally, undifferentiated schizophrenia is the classification developed for people who have several of the characteristic symptoms of schizophrenia—such as delusions, hallucina- tions, or incoherence—yet do not show the typical symptoms of any other subtype of the disorder.
Causes of Schizophrenia Because schizophrenia is a very serious disorder, considerable research has been directed at trying to discover its causes (Keshavan, Tandon, Boutros, & Nasral- lah, 2008; Williamson, 2006). Many studies indicate that schizophrenia has a genetic component (Gottesman, 1991; Hashimoto et al., 2003; P. Lichtenstein et al., 2009). People with schizophrenia are more likely than other people to have children with schizophrenia, even when those children have lived with adoptive parents since early in life. If one identical twin suffers from schizophrenia, the chances are almost 50% that the other twin will also develop this disorder.