Dr Wayne Kampers | Harley Street Psychiatrist | Private Harley Psychiatrist | Harley Street Psychiatry

The Brain's Response to Stress

The anatomy of stress in the brain involves several key regions, primarily within the limbic system, which is the brain’s emotional processing area.

• The areas of the limbic system involved in the stress response are the amygdala, hippocampus, and prefrontal cortex.
• The *amygdala& which is the brains safety center also known as the brains stress alone is responsible for scanning the environment and detecting potential threats.

>>It initiates the body's stress response by rapidly sending signals to other parts of the brain resulting in the triggering of a physiological reaction.

• This is primarily mediated via the autonomic nervous system which results in physical and emotional reactions like an increased heart rate and heightened alertness.
• The hippocampus is essential for memory formation and contextualizing the stressful event. >>It compares current experiences with memories of previous experiences and through a process of predictive coding determines what the appropriate stress response should be
  • It is also responsible for shutting down the stress response once the threat has been resolved.
• the prefrontal cortex is the region of the brain responsible for higher order thinking, decision making and emotional regulation.
  • it rationally assesses the situational threat and its role as the moderator regulates the emotional responses generated by the amygdala.
• The limbic system when in a state of threat physiology, releases stress hormones like cortisol and adrenaline once the hypothalamus has activated the hypothalamic – pituitary – adrenal – axis (HPA Axis)
  • The sympathetic nervous system initiates the fight or flight response preparing the body for immediate action, as if in survival mode.
  • This results in the release of stress hormones like cortisol and adrenaline which caused the physical symptoms associated with the fight or flight mode.
  • Neurotransmitters like serotonin, dopamine, and norepinephrine also play a vital role in this interconnected system, affecting mood, cognition, and behavior under stress.

Types of Stress

• Acute Stress
  • Short-term stress that results in a quick burst of energy and focus, followed by a return to baseline once the threat has passed.
  • Can be beneficial, improving performance and cognitive function.

Chronic Stress

• Persistent stress can lead to serious physical and mental health issues.
  • Prolonged activation of the stress response can cause changes in brain structure and function.

Impact of chronic stress on the brain

• Chronic stress can enlarge the amygdala, making it more reactive and leading to exaggerated stress responses.
• Prolonged stress can cause hippocampal shrinkage, impairing memory formation and stress regulation.
• Stress-induced changes in the prefrontal cortex can impair decision-making, problem-solving, and emotional regulation.
• The physical manifestations of chronic stress are often quite debilitating and can include any or all of the following
  • Tension headaches because of chronic muscle tension.
  • Painful muscle tension often in the neck shoulders and back area.
  • Causing hives or exacerbation of skin problems like eczema or psoriasis.
  • Chronic fatigue with persistent feelings of low energy and exhaustion making day-to-day activities difficult.
• There are various emotional and cognitive symptoms that can accompany the above mentioned physical symptoms including:
  • Pervasive anxiety, worry and fear including anticipatory anxiety, the fear of something in the future over which one has no control but nevertheless debilitates one in the present
  • Pervasive depressive symptoms with feelings of pervasive low mood, a sense of hopelessness, lack of motivation and loss of interest in activities that were previously enjoyable.
  • Increased irritability frustration and a volatile mood.
  • Cognitive difficulties with memory issues, attention problems and difficulty making decisions.
  • Emotional instability and emotional dysregulation because of volatile mood swings.
• Behavioral changes such as sleep disturbance, appetite changes, social withdrawal, self-medication with alcohol and or recreational drugs and procrastination or avoidance behaviours because of the overwhelming feelings of pervasive stress.
• These can all result in long term health issues affecting all organ systems with the increased risk of high blood pressure heart disease and strokes, a compromised immune system with an increased susceptibility to infections and delayed healing from injuries, metabolic problems with the increased risk of obesity and diabetes, chronic pain conditions and the development of mental health issues like anxiety depression and PTSD.

Managing chronic stress

• Stress reduction techniques are the cornerstone of managing chronic stress and include daily therapeutic breathing to calm down the autonomic nervous system, mindfulness-based relaxation techniques, regular exercise to stimulate the BDNF gene which improves the stress response as well as cognition.
• Forging and maintaining connections with self and others.
• This approach enhances neuroplasticity within the brain.
  • Neuroplasticity is the brains capacity to form new neural connections facilitating recovery from chronic stress - induced changes

By recognizing the roles of different brain regions, we can better appreciate why certain techniques are effective and tailor our approach to managing stress.