DO YOU FIGHT OR FLIGHT?
Imagine you are walking in the woods when suddenly, you see a snake. How is your body going to respond? Will you fight or flight? Most people will not have time to think about how they will respond; they will just respond. Thanks to an important system in your body, you do not have tell yourself if you should run from the snake. The Autonomic Nervous System (ANS) regulates numerous involuntary physiological responses such as breathing, heart rate, hormone secretion, or body temperature. You are not concerned with these vital functions because they are usually controlled by the ANS. While for most of us the ANS is generally out of our conscious control, the truth is that the cortex of the brain, normally associated with conscious thought, is able to change the autonomic nervous system to some degree.
Sympathetic Division versus Parasympathetic Division
What exactly is occurring physiologically when you see a snake or sense fear? After you see the snake in the woods, your cortex sends this message to another part of your brain called the hypothalamus. The hypothalamus sends a message to the amygdala (another part of the brain), which sends a message to the peripheral nervous and in turn this message gets sent to the ANS who routes this message to the sympathetic division. While this sounds like a lot of delivery of messages, neurons communicate each other at average of 275 miles per hour. Therefore, your brain is sending messages instantaneously throughout your body.
The sympathetic division, which is one part of the ANS is triggered by threatening or challenging physical stimuli, such as a snake, or by psychological stimuli, such as breaking up with your significant other. Once triggered, the sympathetic division increases the body’s physiological arousal. The flight- fight response, which is a state of increased physiological arousal caused by activation of the sympathetic division, helps the body cope with and survive threatening situations.
Pupils dilate Pupils constricted
Dry mouth Salivation
Goose bumps No goose bumps
Increased heart rate Decreased heart rate
Maximum supply of blood muscles Maximum supply of blood to internal organs
Adrenal glands increased Decrease adrenal activity
Inhibited digestion Stimulate digestion
Sympathetic division increases heart rate, increases blood pressure, dilates pupils, as well as other physiological responses. After you have been physiologically aroused by seeing a snake, it will take some time before your body returns to a calmer state. The process of decreasing physiological arousal and calming down your body is triggered by the hypothalamus which activates the parasympathetic division. A shown in the above chart, the left column shows the body’s physiological arousal being activated by the sympathetic division, while the right column shows how the body response when the parasympathetic division is activated.
Quick tip: next time you are feeling overwhelmed decrease your sympathetic division response by taking a deep breath. This will help increase the parasympathetic division response.
As a neuro-clinical therapist, I assist clients in being able to regulate their ANS to have better control over their physiological responses and to decrease stress responses. I teach many techniques to increase parasympathetic activity. If interested, please attend one of my FREE workshops.
~Dr. D. Moore