What happens in the brain during schizophrenia?

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The modern scientific research proves that schizophrenia is clearly a biological disease of the brain, just like bipolar disorder or Alzheimer’s disease. It’s partly cause by genetics, but it can also be inherited. Furthermore, thanks to modern brain imaging techniques such as MRI and CT, structural differences between the brains of schizophrenics and normal brains have been revealed. However, it doesn’t hurt to know what schizophrenia is and what its characteristics are, so the schizophrenia is a serious mental disorder in which people interpret reality abnormally. It is characterized by the presence of hallucinations, delusions and highly disorganized thinking and behavior in people suffering from this mental disorder, which impairs daily functioning and can cause disability. They also require life-long treatment, but early detection and treatment can help control symptoms before serious complication develop, thereby improving long-term prospects.

People with schizophrenia have up to 25% less gray matter in their brains, especially in the temporal and frontal lobes, an area known to be important for thinking and judgment. Patients with the worst brain tissue loss also have the worst symptoms. Functional scanning of the brain with technologies such as PET or functional MRI has made it possible to create real-time maps of regional brain blood flow and metabolism, providing another chance to see how the brains of schizophrenics differ from normal brains. Such studies have shown low levels of activation in medial frontal cortex and inferior parietal cortex compared to normal people in control subjects. This means that people who tend to have more negative than positive symptoms shown lower brain activity in key brain areas. In short, the schizophrenic brain differs on average in terms of total tissue volume and activity.

In addition to structural difference, the schizophrenic brain also shows neurochemical differences. It is important to know that the brain uses many chemical messengers, i.e., neurotransmitters, to be able to communicate between the millions of neurons in the brain. At a basic level, the schizophrenic brain is differently sensitive to the neurotransmitter dopamine compares to the normal brain. The “dopamine hypothesis” said that schizophrenia is causes by excess dopamine. This is supported by several facts, as drugs known to block the action of dopamine in the brain, also known as antipsychotic drugs, reduce the intensity and frequency of hallucinations. The second fact is that stimulant drugs such as cocaine, which either mimic the effects of dopamine or cause dopamine to become more active in the brain, are known to cause hallucinations and delusions in non-schizophrenic people. While this hypothesis was dominant for a long time, research in recent years is no longer so sure that dopamine is solely responsible for the development of schizophrenia. Neurotransmitters, including serotonin and glutamate, are also thought to be involved. The details of the neurochemical involvement of schizophrenia may change as new findings accumulate, but its basic neurochemical basis is well proved and now seems unquestionable.