The causes of schizophrenia are not yet fully understood.
Researchers do not yet know exactly what causes some people to develop schizophrenia.
There is a very strong genetic component to schizophrenia.However, genes alone do not completely explain the illness.
Verywell / Cindy Chung
Most scientists believe that genes dont cause schizophrenia directly but do make a person vulnerable to developing the disorder.
Scientists are studying many possible factors that might cause a person with a genetic predisposition to develop schizophrenia.
Instead, experts believe that it is a complex interplay of factors that play a part.
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Genetics, environment, lifestyle, family history, and social influences have all been implicated.
What Is Schizophrenia?
Schizophreniais an illness of the brain that causes certain characteristic symptoms, abnormalexperiences, and behaviors.
For different people, schizophrenia can involve different clusters of symptoms.
It is possible that slightly different disease processes are involved in these different clusters.
Family History and Genetics
The evidence of a genetic predisposition to schizophrenia is highly apparent.
The frequency of schizophrenia in the general population is slightly less than 1%.
Being related to someone with schizophrenia, though, greatly increases your risk of developing schizophrenia.
The numbers to support this are strong.
However, genes alone dont cause schizophrenia.
Environment
As with many health conditions, certain environmental factors are also causes of schizophrenia.
There are a variety of traits of viruses that might make this possible.
Infectious disease theories of schizophrenia are very exciting and promising.
Toxins that have been researched to show possible influence include alcohol and lead.
Lead
Lead exposure has also been implicated as one of the causes of schizophrenia.
If a home was painted with lead paint before 1978, it can still release this toxin.
Millions ofneuronsare formed, migrate to different regions of the forming brain, and specialize to perform different functions.
The common element in all developmental theories is that the causal event occurs during the brains development.
Early Disruptions
Developmental theories suggest an early disruption causes the brain structure to be disorganized.
Also, these theories address thewhenof schizophrenias origin, but not the cause itself.
We know this because influencing certainneurotransmitterswith drugs (likeamphetamineor PCP) can cause schizophrenia-like symptoms.
Also,antipsychotic medicationsthat block the action of the neurotransmitter dopamine can effectively reduce symptoms.
In fact,dopamineimbalance was once thought to be a cause schizophrenia.
There are also drugs being developed that may not target dopamine receptor antagonism.
Current research indicates that abnormalities in the neurotransmitters GABA and glutamate are involved in the cause of schizophrenia.
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Psychological stress also aggravates disorders like high blood pressure and heart disease.
This statement doesnt make sense to many people familiar with schizophrenia.
How can it be true?
For one thing, schizophrenia does not become more common after these types of traumas.
Stressalso plays a significant role in the control of the illness.
People with schizophrenia become very sensitive to stress and change.
Psychological stress alone can be enough to trigger an episode.
Developing and maintaining a routine is one of the most important aspects of avoiding relapse.
However, those losses (like relationships, jobs, school, accidents, etc.)
Essentially, previously undiagnosed schizophrenia can be the cause of many life-changing events and not the other way around.
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