Schizophrenia is a group of psychotic disorders characterized by disturbances in thought,
perception, affect, behavior, and communication that last longer than 6 months. There are
5 recognized types of schizophrenia: catatonic, paranoid, disorganized, undifferentiated,
and residual. Schizophrenia is thought to affect about 1% of the population.
The symptoms of schizophrenia are present during the active phase. Delusions,
hallucinations, catatonic behavior, and incoherence are some of the basic symptoms. No
single characteristic is present in all types of schizophrenia. The cause of schizophrenia
is unknown. There are various theories to explain the development of this disorder.
Genetic factors may play a role; relatives of a person with schizophrenia are more likely
to develop the disorder. Psychological and social factors may also play a role in
Childhood-onset schizophrenia begins after 5 years of age, adult onset occurs before the