5 Ways Stress is Changing Your Brain

The body’s stress response is a survival mechanism. When we feel threatened, physiological processes activate the fight-or-flight response to keep us safe. But, the cause and effect relationship is not so simple; the problem is that not all stressors carry the same weight, and our emotions can confuse the body into thinking we’re in grave danger when we’re actually safe. There are different kinds of stress which affect the body differently; when you develop a better understanding of these processes, you’ll be able to deepen the relationship you have with your body and yourself and cultivate healthier coping strategies as you face various stressors in your life.

Different types of stress and how the body responds

Acute stress occurs over shorter time periods and is characterized by the symptoms that immediately follow a stressful event. The body releases hormones to defend itself against danger (real or perceived), and activates the sympathetic nervous system for “fight or flight”. Adrenaline and cortisol are released to make you more alert and vigilant so that you’re better prepared to take on (or flee from) the threat. 

The effects of chronic stress on the body over time can be devastating. This type of stress occurs when ongoing stressors create a fairly constant state of fear, anxiety or worry. Chronic stress often becomes such a consistent part of everyday life for many of us that we push it away rather than dealing with it effectively, creating bigger problems for us in the long run.

There is also such a thing as positive stress, or eustress. Experiencing mild, periodic or situational stress that leads up to a positive experience or results (as with preparing for a wedding or welcoming a new baby, or taking cold dips, fasting and working out) actually has a beneficial impact on physical and mental health. The hormetic effects (or benefits of mild stress) create more resilience in body and mind and have a positive effect on aging and longevity.

When referring to the effects of stress on the brain in this post, we’re mostly talking about chronic stress. As the major stress hormone, cortisol is released to activate the nervous system in stressful situations. To utilize energy most effectively and reduce reaction time, cortisol turns off biological functions that are nonessential to the immediate response. It suppresses the digestive system, impairs the immune system, and impacts the reproductive system. Chronic stress contributes to inflammation and affects regions of the brain responsible for regulating mood, fear and motivation. It can also cause or exacerbate brain fog, depression, anxiety, and sleep disorders. 

Here are 5 major ways stress is changing your brain:

1. Stress changes your circadian rhythm - Your circadian rhythm is the internal body clock that regulates your sleep-wake cycles over a 24-hour period. Cortisol and melatonin have an inverse relationship and are closely related to these biological rhythms; cortisol is the body’s natural alarm clock, while melatonin signals that it’s time for bed. Chronic stress causes cortisol levels to rise while melatonin decreases, contributing to more difficulty falling asleep and staying asleep. Lack of sleep impairs memory, concentration, focus and judgment. And, poor/irregular sleep increases activity of the HPA axis (which produces cortisol and regulates its levels), creating more arousal in the body and making it even more difficult to achieve consistent, high quality sleep. 

2. High cortisol = low progesterone = low GABA - In my post about the impact of hormonal imbalance on mental health, we looked at the relationship between cortisol, progesterone and GABA. When cortisol levels increase, progesterone decreases, and when progesterone levels drop, the production of gamma-aminobutyric acid (GABA) also declines. GABA is a naturally occurring amino acid and has an inhibitory effect on certain nervous system activity that leads to anxiety, depression and sleep disorders. GABA is important for promoting good mood, steady sleep patterns and a sense of calm, and when this neurotransmitter is low, it can lead to increased anxiety, disturbed sleep, and instability with mood.

3. Stress makes you more vigilant and less trusting - hypervigilance and difficulty trusting and opening up to others are common trauma responses. Stress isn’t always related to trauma, but chronic and unresolved stress can create the same overactivity in the amygdala (increasing heart rate and blood pressure), and lead to a state of constant emotional tension and even hyperarousal. Stress tells the brain we need to protect ourselves, and that naturally makes us less trusting of others.

4. Stress increases the feeling of being unsafe - Hypervigilance is directly related to our sense of safety and perceived threat. When cortisol is elevated over extended periods (and GABA and progesterone are depleted), the body is in a constant state of sympathetic nervous system activation, creating feelings of unrest and distrust. The prefrontal cortex is associated with high level functions and responsible for signalling safety. When we’re chronically stressed, this region of the brain tells us we’re not safe and should be ready to react at any moment. There’s dysregulation here and a maladaptive response, as the body becomes more highly attuned to a sense of safety (or lack thereof), but less equipped to respond appropriately to real stressors or threats when they do arise.

5. Stress stops or interferes with healthy neuronal connections - Chronic stress changes the chemicals in the brain responsible for regulating mood and cognitive function. One of these neurotransmitters is serotonin, which is the primary hormone related to feelings of happiness and wellbeing. Chronic stress also leads to increased inflammation, and the hippocampus - the region of the brain related to memory and learning - seems to be particularly vulnerable to these effects.

While we may feel as though we’re avoiding some intensity when repressing feelings around chronic stress, the biological response remains the same and the impact on the brain can be far-reaching. The good news is that the brain is incredibly malleable and resilient, capable of literally rewiring and restoring itself to healthy, balanced function. Discoveries around neuroplasticity have proven the brain’s ability to heal and change.

We can encourage this reorganization of neuronal activity through lifestyle practices like meditation, exercise, grounding in nature, practicing proper sleep hygiene, nurturing social connections and fuelling the body and brain with the nutrients we need to thrive. At Divine Elements, we also offer biohacking therapies and neurofeedback services that improve the brain’s ability to self-regulate, maintain flexibility, and smoothly shift between states of relaxation and arousal.