"The grey drizzle of horror," author William Styron memorably called depression. The mood disorder may descend seemingly out of the blue, or it may come on the heels of a defeat or personal loss, producing persistent feelings of sadness, worthlessness, hopelessness, helplessness, pessimism , or guilt . Depression also interferes with concentration , motivation , and other aspects of everyday functioning.
The Biology of Depression
Depression makes deep inroads on biology to bring about the many symptoms of depression, from sleep disruption and inability to experience pleasure to lack of motivation and feelings of guilt. Because of its complexity—and because the disorder contributes so much to human suffering—the biology of depression is a major subject of ongoing research.
Overexcitability of the stress response system, shifts in activity of various neurochemicals in the brain, diminished efficiency of nerve circuitry and nerve generation, disturbances in energy use in nerve cells, the intrusion of inflammatory substances in the brain, upsets in the brain’s 24-hour (circadian) clock—all play a role in depression onset or progression and influence the kind and severity of symptoms.
For more see The Biology of Depression
Explore More About Depression
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