Your Brain and Chronic Stress

We live in a 24/7/365, always on world. This can contribute to stress, a lot of it. We’re probably all familiar with that feeling of acute stress. You know — you overslept and that important meeting is this morning. The computers went down, and you hadn’t saved your report…yet. 

All of these circumstances can cause acute stress. Somehow we survive the situation. Sometimes we even laugh about it later. But what about chronic stress? That’s a different beast. Have you, or someone you know, ever been hit with a heavy stress burden? If so, you have felt, or witnessed in someone else, the negative changes that can happen to your brain.

Chronic stress affects almost every part of your body, and your brain can suffer many serious consequences. Here are five:

Stress Impairs Memory

Your brain is incredibly flexible and versatile, able to respond to various stimuli and react accordingly. Chronic stress leads to the production of cortisol, the stress hormone. Cortisol causes shrinkage of  the hippocampus, a region of the brain which is very important for memory and retention. 

Instead, it causes an increase in the size of the amygdala, a brain area that is deeply entwined with our emotional reactions. By increasing the size of the amygdala, the brain is primed to respond to the fight or flight stimulus, and make decisions based on emotions rather than working memory and logic. Not an ideal scenario.

Stress Increases Oxidative Damage In The Brain

Glutamate is a neurotransmitter in the brain whose production is amplified by cortisol. However, as glutamate increases, so does the generation of free radicals, dangerous molecules that actively damage cells. These oxygen species attack and cause brain cells to die. They have been implicated as contributing factors in the development of Alzheimer’s and Parkinson’s.

Stress Inhibits Growth Of New Brain Cells

Things would not be so dire if following oxidative damage new cells formed, but stress has a way of shutting down this mechanism of recovery as well. In particular is a protein named Brain-Derived Neurotrophic Factor, (BDNF), which stimulates the formation of new brain cells, and which is suppressed by cortisol. This speeds up aging and deterioration of the brain and can explain why some people experience significantly more cognitive issues under high stress.

Stress Negatively Affects Neurotransmitters Levels

Neurotransmitters have very important functions in the brain. Their most well established roles include those of regulating mood, motivation and concentration and sleep patterns. Cortisol provokes depletion of two of these, serotonin and dopamine. This leaves you lethargic and unable to experience pleasure in everyday life. The result is often depression and suicidal thoughts, along with panic attacks and uncontrolled binge eating.

Stress Affects The Brain’s Defense

The brain possesses a natural “barrier,” the blood-brain barrier. Under normal circumstances this barrier prevents entry to questionable elements. That includes toxins and the majority of pathogens that cause disease. However, cortisol causes this barrier to become much more lenient. More and more unfavorable elements gain entry into the brain. This is extremely bad. The only time this is beneficial is when you need a particular medication to cross the barrier.

Stress Reduces The Plasticity Of The Brain

As previously mentioned, the brain is able to constantly grown and change. Plasticity also refers to the brain’s ability to rewire itself. For example, someone who learns a new highly technical skill has neurons that are more tightly interconnected to other neurons that participate in getting a particular task done. With practice, this network grows even stronger. That’s why practice makes perfect, and why when you are under stress it becomes increasingly difficult to learn, retain or perform.