Dear Bob,
You ask for a greater understanding about stress and how it can affect the body and mind. So I have carried out some research and offer the following.
Stress does seem to be an unavoidable element of modern life. Acute stress is the hard wired physiological reaction to an immediate threat. This reaction is known as the ‘fight’, ‘flight’ or ‘freeze’ response. Once the threat has passed the levels of stress hormones return to normal with little effect on the body. It is now accepted that some acute stress is desirable as it prepares your brain for performing well. The stress hormone adrenaline is produced in these moments of acute stress, as well as when we get excited. Adrenalin helps you to think and move quickly. It is the ‘life- saving’ hormone.
What is a problem though is chronic stress. This can seriously damage the immune system making you vulnerable to a range of physical ailments. Chronic stress can have an impact on the brain and how it functions. It is chronic stress that can wear out your adrenal system. Also when you experience over arousal then adrenalin and cortisol become chronically high in the blood stream. Cortisol is a stress hormone that is ever present in the system but when it is in excess can cause a range of health challenges such as, hypertension, strokes, heart disease, headaches, weight gain, decreased sex drive, muscle tension, chronic fatigue, digestive problems and diabetes.
So Bob, as most people are aware chronic stress can have quite an impact on the body. What is less known is the impact of chronic stress on the brain. There are quite a few and I have selected some key ones.
Stress can be indicated by becoming more forgetful. Studies show that when you are stressed electrical signals in the brain associated with factual memory are weakened.
The amygdale is considered the brain’s thermometer for feelings and is part of the limbic system. The quirk of the amygdale is that when stimulated it becomes aroused in proportion to the strength of an emotional response, so being in a state of continuous chronic stress will simultaneously highly activate the amygdale. When stimulated the amygdale mostly associates with what are called ‘away’ feelings such as anxiety and fear. This results in a cycle of fear and anxiety.
Chronic stress can limit levels of neurotransmitters such as serotonin and dopamine. These neurotransmitters are chemicals and are how the brain cells communicate with each other. Serotonin has a large role in mood, learning, appetite and sleep. Dopamine is the neurochemical of ‘interest’ or motivation. Too little dopamine can result in you feeling unmotivated and lethargic. Serotonin based depression is accompanied by anxiety and irritability and dopamine based depression manifests as lethargy and a lack of ‘joie de vie.’
Cortisol can impair the production of new neurons in the hippocampus. The hippocampus is critical in learning, storing memories and regulating emotions. Stress can also shrink the pre frontal cortex which is responsible for decision making and memory.
Well Bob, what do you think about what you have read? Do you feel more informed about stress, anxiety and depression? In a future letter I will discuss further the relationship between stress, anxiety and depression. I will continue to offer suggestions on how to minimize stress. manage anxiety and move out of depression.
Understanding and awareness are steps forward Bob,
Stay curious,
Fi x
