Depression affects how people think, feel and behave. Some experience mild depression just once or occasionally, while others have severe depression throughout their lives.
This more intense form of depression is called major depressive disorder (MDD).
"Major Depressive Disorder, arises in roughly three to five percent of all males and eight to 10 percent in females," reported Medical Daily.
Many studies have shown there is a change in brain activity when someone is depressed. But what else happens to your brain when you’re depressed?
When it comes to depression, the brain’s hippocampus, prefrontal cortex and amygdala are involved.
Located near the brain’s center, the hippocampus regulates the hormone cortisol. Cortisol is released during physical and mental stress and depression.
Complications occur when extreme amounts of cortisol end up in the brain after such stress.
These high cortisol levels are thought to be part of the problem.
Researchers believe that they’re the lead in changing the brain’s physical structure and chemical activities, which can prompt the onset of MDD.
Cortisol levels are normally highest in the morning and decrease at night. People with MDD have cortisol levels that are always elevated, wrote HealthLine.com.
It’s this long-term exposure to elevated cortisol levels that may slow new neuron production and cause the neurons of the hippocampus to to reduce in size. Simply stated, the brain shrinks.
A global meta-analysis compared 8,927 people’s hippocampuses. Of those studied 1,728 had major depression. The rest had mild depression or were healthy.
Researchers found that the more depressive occurrences someone had, the more their hippocampus decreased in size. Basically, the longer someone was depressed, the more it was found that their brains shrank.
The prefrontal cortex, located in the front of the brain, regulates emotions, makes decisions and forms memories. If there is an excess of cortisol, the prefrontal cortex has also been found to shrink.
The amygdala enables emotional responses.
Cirino, Erica. "The Effects of Depression on the Brain." Healthline. N.p., n.d. Web. 03 May 2016.
Davey, Melissa. "Chronic Depression Shrinks Brain's Memories and Emotions." The Guardian. Guardian News and Media, 2015. Web. 03 May 2016.
Weller, Chris. "Depression Shrinks The Brain, And Now Scientists Know Why." Medical Daily. N.p., 2014. Web. 03 May 2016.