Schizophrenia is clinically diagnosable mental disorder in which a person experiences delusions, hallucinations, or episodes of abnormal thoughts and behavior. Neuroscientists and psychologists believe that there may be many potential schizophrenia causes, though professionals often have trouble pinpointing the exact source of a patient's woes. Experts generally agree that both biological and environmental factors can contribute to the illness. A patient may be genetically predisposed to the condition or develop symptoms because of a severe infection or brain injury. Excessive stress and poor nutrition in an expecting mother is also correlated with schizophrenia in her child.
Inheritable biological factors are believed to be leading schizophrenia causes. Scientists have identified a number of genes that, when expressed, are correlated with the development of schizophrenia. If both parents carry certain predisposing genes, it is possible that their child will suffer from schizophrenic episodes at some time in his or her life. A person with a familial history of mental disorders is thought to be at a significantly higher risk of developing schizophrenia symptoms.
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In most cases, it is difficult or impossible to ascertain that genetics is the sole cause of schizophrenia in a person. Researchers believe that the condition of a mother can also contribute to the disorder in her offspring. Clinical studies suggest that stress, drug and alcohol use, and illness may all be prenatal schizophrenia causes. When the developing fetus is exposed to environmental toxins or robbed of important nutrients, its brain chemistry may be negatively affected. Stress levels or infections in expecting mothers are suspected to result in insufficient or irregular distribution of hormones, which can cause further developmental issues.
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It is also possible for an individual to develop schizophrenia from environmental causes later in life. Simply living in a hectic, noisy, urban environment appears to be a risk factor for schizophrenia, perhaps because of higher stress levels. Air pollution and toxins in cities may also affect the brain in ways that researchers have yet to fully confirm. Severe infections, influenza, and chronic respiratory problems are all correlated with increased risk for mental problems, though they have not been confirmed as direct schizophrenia causes.
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Finally, substance abuse appears to be among the most prominent schizophrenia causes in adults. Frequent or long-term drug use, especially cocaine and methamphetamine, can alter the brain's ability to release and regulate certain neurotransmitters. This can set the stage for a number of psychoses, including schizophrenia.
A person who shows signs of schizophrenia or believes he or she may be at risk of developing the disorder should visit a psychologist or doctor for testing. If a diagnosis is confirmed, an individual has many treatment options in the form of medications and behavior modification therapy. With regular treatment, most patients with schizophrenia are able to successfully manage the condition and lead normal, healthy lives.