Causes of Schizophrenia
Many environmental factors have been suggested as risk factors for schizophrenia, including:
- Exposure to viruses
- Malnutrition in the womb
- Problems during birth
- Psychosocial factors, such as stressful environmental conditions.
It is likely that an imbalance in the complex, interrelated chemical reactions of the brain plays a role in schizophrenia. Imbalances of the neurotransmitters dopamine and glutamate (and possibly others) are currently being studied. Neurotransmitters are substances that allow brain cells to communicate with one another. Basic knowledge about brain chemistry and its link to schizophrenia is expanding rapidly and is a promising area of research.
The brains of people with schizophrenia look a little different from the brains of healthy people, but the differences are small. Sometimes, the fluid-filled cavities at the center of the brain, called ventricles, are larger in people with schizophrenia. Also, the overall gray matter volume is lower, and some areas of the brain have less or more metabolic activity than normal.
Microscopic studies of brain tissue after death have also revealed small changes in the distribution or characteristics of brain cells in people with schizophrenia. It appears that many of these changes occurred in the womb, because they are not accompanied by glial cells, which are always present when a brain injury occurs after birth. One theory suggests that problems during brain development lead to faulty connections that lie dormant until puberty. The brain undergoes major changes during puberty, and these changes could trigger psychotic symptoms.
The only way to determine conclusively what causes schizophrenia is to conduct more research. Scientists throughout the world are studying this disorder and trying to develop new ways to prevent and treat it.