Stress and Your Brain

By Cindy Williams, RN

Director, Health Ministries

Stress. What is your first thought when you hear that word? Is it a positive or a negative thought? I have asked my high school health class this question many times. The students always consider stress to be negative and something to figure out how to avoid at all cost. 

What is stress? Stress is how our brain and body respond to any demand. Any kind of demand can be a stressor: exercise, work, school, riding a roller coaster, going on a date, life changes, and traumatic events. Many of these stressors are positive and are “good” stress or eustress, as psychologists call it. Eustress is what we feel when we get excited and anticipate and experience something good. It keeps us feeling alive and excited about life. We need good stress in our lives. 

We can also experience acute stress. I think this is what most of us think of when we think of stress. We have a looming deadline at work or school, experience an automobile accident, lose a job, or a relationship goes sour suddenly. Our body responds nearly instantaneously to help us fight the threat off or flee to safety. I doubt there is anyone reading this who has not experienced this “fight or flight” effect. 

This response begins in the brain. Our senses send information to the amygdala where the images, sounds, and smells are interpreted. If it perceives danger, it sends a distress signal to the hypothalamus. The hypothalamus communicates with the autonomic nervous system (ANS), which controls blood pressure, breathing, heart rate, and the constriction and dilation of key blood vessels and the bronchioles. The sympathetic part of the ANS acts like a gas pedal and provides the body with a burst of energy to that it can respond to perceived danger. Messages are sent to the adrenal glands to pump adrenaline into the blood stream. The heart rate increases, blood pressure increases, the bronchioles open up to allow extra oxygen in with every breath, senses become sharper, the brain is more alert, and glucose and fats are release from temporary storage sites in our body. These things happen in a split second, often before we even have time to process the threat to us.

Additional hormonal signals are sent out if our brain continues to perceive the situation as dangerous. These signals cause the adrenal glands to release cortisol which keeps the “gas pedal” down. When the threat passes, cortisol levels fall and the parasympathetic part of the ANS puts on the “brake” and dampens the stress response.

God provided us with an amazing way to deal with the threats that come our way each day. But what happens when the stress doesn’t go away? What happens to our body and our brain then? Can stress effect our immune system? How can we effectively deal with chronic stress? I’ll look at these topics in future health tips.

References

https://www.nimh.nih.gov/health/publications/stress/index.shtml

https://www.health.harvard.edu/staying-healthy/understanding-the-stress-response

https://www.stress.org/when-stress-is-actually-good-for-you

This article is part of a continuing series of health during these COVID times. For other articles, please see www.uccsda.org/healthministries.

Photo by Francisco Moreno on Unsplash.