“Sometimes the most important thing in a whole day is the rest taken between two deep breaths.” Etty Hillesum
Stress is the notion that encapsulates the body's natural response to a particular stressor, whether it is environmental, biological, emotional, or physical. While everyone experiences certain levels of stress from time to time, it is perceived and manifested differently by each individual. When we encounter stress—whether minor or significant—changes or developments in our environment may occur, prompting our bodies to elicit stress responses that help us adapt to new circumstances. However, the elicited stress response may depend on the type of stress being cultivated and its varying etiology. The Cleveland Clinic (2024) identifies the following three main types of stress: acute stress, episodic acute stress, and chronic stress and their respective descriptions.
- Acute Stress: “Short-term stress that comes and goes quickly. It can be positive or negative” (Types of stress section).
- Episodic Acute Stress: “Episodic acute stress is when you experience acute stress on a regular basis. With this kind of stress, you don’t ever get the time you need to return to a calm, relaxed state” (Types of stress section).
- Chronic Stress: “Chronic stress is long-term stress that goes on for weeks or months. You may experience chronic stress due to marriage troubles, issues at work or financial problems. It’s important to find ways to manage chronic stress because it can lead to health issues” (Types of stress section).
While the understanding of acute and episodic acute stress is undeniably crucial in the development of our body’s reactions to stress and its subsequent responses, chronic stress is highlighted for its numerous impacts on our physiological and psychological wellbeing.
What Happens to the Brain During Stress?
As humans, we have an innately designed, built-in stress response known as our “fight or flight response.” This response is triggered by the autonomic nervous system (ANS), more specifically, the sympathetic nervous system, where hormones such as adrenaline and cortisol are released. These “fight or flight” hormones stem from a “perceived” threat and can increase heart rate, blood pressure, muscle tension, and hyper or hypo arousal (Cherry, 2024). While this response to threat is adaptive in moments of danger, it can become maladaptive as it can perpetuate constant feelings of arousal and hormone secretion, leading to increased risk for physical and or mental health difficulties.
Chronic Stress and Brain Structures
Researcher Kenneth Blum at the Massachusetts Institute of Technology (2024) discovered that chronic stress can significantly impact the brain function and structure in the following ways:
- Shrink the hippocampus: This area of the brain plays a crucial role in memory and learning. When stressed, the hippocampus can reduce in size, leading to difficulties with memory and concentration. Chronic stress can further hinder the hippocampus’s ability to form new neurons, known as neurogenesis, potentially contributing to mood disorders and depression.
- Over-activate the amygdala: The amygdala plays a crucial role in processing fear, anxiety, and emotional responses. Chronic stress can make it more reactive, causing heightened reactivity and emotional sensitivity.
- Hormone Disruption:
- Serotonin, a hormone crucial in mood regulation, may become diminished and reduced, leading to mood disorders and hindering healthy coping mechanisms.
- Dopamine, a hormone crucial in motivation and reward processing, may become diminished and reduced, leading to anhedonia, depression, and addiction.
- Impair the prefrontal cortex: This part of the brain governs decision-making, attention, impulse control, and emotional regulation. Stress can reduce its effectiveness, making it harder to manage emotions, problem solve, and think clearly.
How Chronic Stress Affects Body Health
Adapted from the Los Angeles Outpatient Center (2025), the following image illustrates the variations in physical, emotional, behavioral, and cognitive symptoms curated by levels of stress.
Breaking the Cycle: Managing Stress for Brain Health
Although chronic stress can impact the brain, our brains also have an extraordinary ability to adapt to increased stressors and stress responses. With intentional care and attention, we can support our recovery from chronic stress and work to foster greater resilience and adaptive recovery.
Stress management techniques are pivotal in breaking the cycle from chronic stress and its impact on brain health and development (Blum, 2024).
Mindfulness and meditation: These practices help calm the nervous system by strengthening the ability to tolerate distress and emotionally regulate, thereby reducing anxiety and improving quality of life.
- Regular physical activity: Exercise releases endorphins and supports brain health.
- Adequate sleep: Sleep helps the brain process emotions and recover from stress.
- Healthy social connections: Supportive relationships can buffer stress effects.
- Professional support: Therapy can provide tools for coping and healing.
References
- Blum, K. (2024).The Impact of Chronic Stress on Brain Function and Structure. Neuroscience and Psychiatry: Open Access, 7(5), 262-264. https://www.openaccessjournals.com/articles/the-impact-of-chronic-stress-on-brain-function-and-structure.pdf
- Cherry, K. (2024). What is the fight or flight response? Verywell Mind. https://www.verywellmind.com
- Cleveland Clinic. (2024). Stress. https://my.clevelandclinic.org/health/diseases/11874-stress
Los Angeles Outpatient Center. (2025). What Are The Key Signs Of Stress Affecting Mental Health? https://laopcenter.com/mental-health/stress-signs/
