The Chemistry of Fear
In writing this article I’m speaking to what happens to the chemistry in our body from the stress and anxiety we all have from time to time. All of this stems from FEAR and is influenced by many genes. There is no such thing as a simple “fear” gene that is inherited from one generation to the next. The genes controlling our neurotransmitters and their receptors are all present in several different forms in the general population.
Some combinations of these different forms you receive from your parents and will predispose you to respond with greater or lesser degrees of fear to events in your environment. But the degree to which your lives are affected by inherited genes will depend to a very large extent on your individual history of events that set off such reactions in the first place.
What happens when you encounter a potentially harmful stimulus is a chain reaction. The amygdala is the part of your brain that receives information from many parts of the brain and interprets this information to generate the emotion of fear.
When the amygdala generates a fear emotion, it sends impulses to another part of your brain, the hypothalamus. Then the hypothalamus sends messages to many other parts of your body to trigger a fight‐or‐flight response. Many of your body systems then undergo significant changes giving you a burst of energy to defend yourself. Your fight‐or‐flight responses are reactions that you automatically and habitually make to increase your chances for survival. The interesting thing is that science is telling us that you are also more likely to pass on these genes to your offspring.
Fight‐or Flight Response
The fight and flight response require food and oxygen for cellular respiration that provides the energy to increase the activities of parts of the body. They are necessary for vigorous muscle activity such as the circulatory system and respiratory system. These systems increase the delivery of oxygen and food to your muscles. The cellular respiration in your muscles uses the oxygen and food to provide energy for fighting or running but, it also inhibits or decreases the activities of parts of your body that are not immediately essential in the moment, such as your digestive system, your immune system, and your reproductive system.
The hypothalamus sends messages to many different parts of your body, through the sympathetic nervous system. The nerve impulses travelling through the branches of the sympathetic nervous system very rapid but are relatively brief.
Fear Hormones and the Endocrine System
Hormones are another way the messages travel to many different parts of the body through your bloodstream. These are actual chemical messengers, secreted by the endocrine system. The adrenal gland is an endocrine gland that produces two fear hormones—adrenaline and cortisol.
Fear hormones are secreted by the adrenal gland, circulating through the bloodstream to all cells of your body. The effect of adrenaline is similar to the effect of the sympathetic nerve action.
Adrenaline increases heart rate and breathing rate, by dilating blood vessels to the lungs and muscles. This decreases blood flow to the brain and decreases digestion.
Cortisol increases blood sugar level by converting stored glycogen and fats into blood sugar it also suppresses the immune response and inflammation.
The fear hormone action that takes place in the body explains why you may feel the fight‐or‐flight response even after you realize there really is no danger. These hormones result in a longer lasting and more widespread fight‐or‐flight response than the effects of the nervous system.
So, how do You Recover from a Fear Response?
The Parasympathetic Nervous System
The good news is that your body cannot maintain a prolonged fight‐or‐flight response. After you have fought or fled what was considered a dangerous situation, your body needs to shut down the fight‐or‐flight response and return to normal. The reversal of the fight‐or‐flight response is caused by the actions of the parasympathetic nervous system. Once again, this system consists of branching nerves that carry nerve impulses to many parts of your body. It causes your body to return a balanced state, know as homeostasis, by relaxing and restoring basic life processes needed for maintaining your health.
Fear and Your Health
We all have problems in life such as work, school, money, social problems, and medical problems that can trigger a long-term fight‐ or‐flight response. Daily life can involve many experiences that we perceived as threatening. Even worrying about things that “might” happen in the future can trigger the same response as actually experiencing it.
Chronic Stress occurs when the fight‐or‐flight response does not shut down to allow for the proper balance between fear and relaxation. This does increase a person’s risk of health problems such as:
- The fight‐or‐flight response uses calories increases the urge to eat after running. But, eating in response to daily stresses can lead to weight gain.
- Stress increases cortisol levels causing elevated blood sugar levels that can lead to both weight gain and diabetes
- Remaining in the fight‐or‐flight response causes blood pressure and heart rate to remain high, putting an extra strain on blood vessel walls.As a result, the linings of blood vessels can become damaged.
- An interruption of blood flow to the heart can lead to a heart attack. Blood vessels in the brain can also be blocked, resulting in brain‐damaging strokes.
- People suffering from stress secrete cortisol at much higher rates than normal people. There is evidence that abnormally high cortisol levels may actually be the initial trigger for depression in some individuals.
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Sleep deprivation is often caused by high cortisol levels resulting in a lack of normal amounts of sleep.
- Stress also affects the function of the immune system, your body’s natural means of fighting off infection. Stressed individuals produce lower levels of antibodies when exposed to pathogens.
- Stress also produces higher levels of cytokines, inflammation triggering chemicals secreted when fighting infections. Excessive inflammation is thought to increase the risks for heart disease, diabetes, and some forms of cancer.
So, in conclusion we need to learn how to deal with our FEAR. Feeling stressed mentally and physically will lead to serious health consequences. It is important to consult a professional to discuss the causes of your fears and learn about specific actions you can take to reduce your stress.
… love and light, Christina
