The concept of the functionality of some mental illnesses should be a thing of the past. An unidentified reason is not a reason to talk about the functionality of mental illness. Advances in technology have made it possible to find the cause of some mental illness. Changes in brain structures in patients with major depressive disorder and bipolar disease were revealed using high-resolution MRI and neuroimaging methods – positron emission tomography, single-photon emission computed tomography. A decrease in the size of the hippocampus , amygdala, orbitofrontal , dorsolateral, anterior cingulatezones of the frontal lobe of the brain, basal ganglia. There was also a change in blood flow in the same areas of the brain, plus in the nuclei of the thalamus. Similar anatomical and functional changes were observed in patients with depression and other diseases: stroke, Alzheimer’s disease, Parkinson’s. In addition, depression is a risk factor for epilepsy, stroke, Parkinson’s disease. It also leads to a negative outcome of many neurological diseases. It is possible that bipolar and depressive disorders are neurological diseases with psychiatric manifestations. The capabilities of functional imaging technology revealed a decrease in activity in the dorsolateral prefrontal cortex and an increase in cerebral blood flow and metabolism in the amygdala, the ventral part of the striatum, subgenual cingulum with depression.
In bipolar depressive disorder, metabolism in the dorsolateral prefrontal cortex is decreased and metabolism in the thalamus and amygdala is increased. Since these areas are associated with the regulation of emotions, the connection with depression becomes apparent. The etiological cause of bipolar disorder is changes in the subgenual prefrontal cortex, amygdala, striatum. When these structures are damaged, a high level of cortisol with its neurotoxicity and impaired neurogenesis are observed . There can be several conclusions from this data:
- no mental illness without structural changes in the brain;
- psychiatry and neurology should be combined into one specialty;
- treatment should be directed to the focus of brain damage, and not to the consequences.