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What is the chemical imbalance that causes schizophrenia?
One frequently asked question about schizophrenia is if it is hereditary. As with most other mental disorders, schizophrenia is not directly passed from one generation to another genetically, and there is no single specific cause for this illness. Rather, it is the result of a complex group of genetic and other biological vulnerabilities, as well as psychological and environmental risk factors. Biologically, it is thought that people who have abnormalities in the brain neurochemical dopamine and lower brain matter in some areas of the brain are at higher risk for developing the condition. Other brain issues that are thought to predispose people to developing schizophrenia include abnormalities in the connections between different areas of the brain, called default mode network connectivity. Recent research is emerging that implicates potential abnormalities in the transmission of the brain neurochemical glutamate as a risk factor for having schizophrenia.
Schizophrenia is thought to have a significant but not solely genetic component. Genetically, schizophrenia and bipolar disorder have much in common, in that the two disorders share a number of the same risk genes. However, the fact is that both illnesses also have some genetic factors that are unique. There are some genetic commonalities with schizophrenia and epilepsy, as well.
Environmentally, the risks of developing schizophrenia can even occur before birth. For example, the risk of schizophrenia is increased in individuals whose father is of advanced age or whose mother was malnourished or had one of certain infections during pregnancy. Difficult life circumstances during childhood, like the early loss of a parent, parental poverty, bullying, witnessing domestic violence; being the victim of emotional, sexual, or physical abuse or of physical or emotional neglect; and insecure attachment have been associated with increased risks of developing this illness. Using drugs, particularly marijuana (cannabis), amphetamines, and hallucinogens, has been found to increase the risk of developing schizophrenia. Factors like recent migration, being discriminated against, and how well represented an ethnic group is in a neighborhood can also be a risk or protective factor for developing schizophrenia. For example, some research indicates that ethnic minorities may be more at risk for developing this disorder if there are fewer members of the ethnic group to which the individual belongs in their neighborhood.
For more information, read our full medical article on schizophrenia symptoms, signs, treatment, and prognosis.