About 75 percent of all cases develop the disease between the ages of 15 and 25. While the incidence is low, the disease tends to be chronic, causing a major disruption of the victim's life. Recent studies have shown that more individuals with schizophrenia make a partial or complete recovery than was previously thought. Schizophrenics often suffer disturbances in mood and behavior. Some patients seem to feel no emotions, but others may display inappropriate emotions, such as laughing at sad situations.
Some schizophrenics withdraw from their family and friends.
Others develop extreme delusions and suffer additionally from hallucinations, most commonly the hearing of voices. Physicians do not know the cause of schizophrenia. However, there is increasing evidence that the disease results from an inherited defect involving certain brain chemicals. These chemicals, called neurotransmitters , enable the nerve cells of the brain to communicate with one another. Schizophrenics may be born with a defect that causes certain brain cells to release excess amounts of dopamine , a neurotransmitter.