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Center  Select An Article Font Size  Schizophrenia and Other
Psychotic Disorders   What Causes Psychotic Disorders?  The
exact cause of psychotic disorders is not known, but researchers
believe that many factors may play a role. Some psychotic
disorders tend to run in families, suggesting that the tendency,
or likelihood, to develop the disorder may be inherited.
Environmental factors may also play a role in their development,
including stress, drug abuse, and major life changes.  In
addition, people with certain psychotic disorders may have an
imbalance of certain chemicals in the brain. They may be either
very sensitive to or produce too much of a chemical called
dopamine. Dopamine is a neurotransmitter, a substance that helps
nerve cells in the brain send messages to each other. An
imbalance of dopamine affects the way the brain reacts to
certain stimuli, such as sounds, smells, and sights, and can
lead to hallucinations and delusions.  How Co