When the human body first experiences stress adrenaline takes over and causes a chain-reaction within the nervous system. The heart begins to beat faster, the sizes of the blood vessels are changed, and the body actually prepares itself for a frightening or emotional event. Even though the humans that are in existence today are not in constant physical danger from wild predators as our pre-historic ancestors were, we still experience this familiar fight-or-flight reaction due to a great deal of different types of stressors.
There are two main types of stress experienced by humans, either chronic or that which is emergency-induced. The chronic type of stress can be particularly harmful to the brain because of hormones and chemicals referred to as glucocorticoids or GCs. When the body experiences a rush of adrenaline which is accompanied by stress, a portion of our brain called the adrenal cortex begins to release these GCs which are useful for dealing with the emergency-type of stressors.
Chemicals such as cortisol, hydrocortisone, and corticosterone act together to increase the production of glucose, constrict blood vessels and essentially help our brains deal with or regulate stress. The GCs tell our brain either to calm down or to boost its levels of awareness and reaction in order to deal with the issue at hand. These glucocorticoids also affect memory functioning, especially in the hippocampus region of the brain.
While the GCs may help us remember frightening or stressful events so that we are better able to deal with them in the future, they can also be harmful to the delicate neurons of the brain. Prolonged periods of stress or depression may actually lead to the damage or even the death of certain neurons, especially those within the memory center of the brain.
It is important to remember that different people react differently to stressors; one person may be able to move on from a trying event while another may suffer from serious psychological effects from a similar event or situation. Learning if your stress is chronic or acute is critical for counteracting the negative affects it has on the brain. Those people who are prone to anger, anxiety, depression, and who suffer from low self-esteem are far more likely to experience damage to the brain than their calmer, more relaxed peers.
Most every one of us experiences bouts of depression or periods of the blues at some point in our lives, but a person who is constantly angry or depressed may require medical or professional assistance. While it may be possible to recover from depression through various means such as drug therapy or counseling, the long-term effects on the brain are still largely unknown. Doctors have recently reported that as many as fifty percent of patients who experienced periods of major depression also possessed high levels of cortisol, which as we know can have negative effects on the brain and cells.
A recent study conducted by The Washington University School of Medicine located in St. Louis, Missouri has shown conclusive evidence of damage to the brains neurons in people suffering from depression. Even those people who had been depressed years prior to the testing still showed signs of brain damage, as much as 12-15 percent cell atrophy in their hippocampus, resulting in the loss of an infinite number of memory cells.
Aerobic exercise is an excellent way to reduce stress and its negative effects on the brain. By engaging in some sort of physical activity the body is able to relax, relieve levels of tension and stress, and burn off nervous energy all at the same time. Endorphins, which are the feel good chemicals produced within the brain, are dramatically increased when we exercise which in turn makes both the body and the mind feel better. Not surprisingly, self-esteem can also even be lifted with regular exercise as well as an increased overall body image.
In his book Saving Your Brain, Dr. Jeff Victoroff theorizes that the cultural evolution and fast-pace of society today has essentially overwhelmed the capabilities of the brain. However, by simply relaxing, slowing ourselves down and learning how to better deal with the common stressors of every day life we can literally save ourselves from brain damage.