*PTSD

Post-Traumatic Stress Disorder (PTSD)

  • Definition: PTSD is a severe anxiety disorder that can develop after exposure to extreme stress or trauma, involving ongoing psychological and physiological reactions long after the threat has passed.

Four Common Features of PTSD:

  1. Severe Anxiety and Physiological Arousal

  2. Painful, Uncontrollable Reliving of the Event

  3. Emotional Numbing and Avoidance

  4. Intense Survivor Guilt

Core Symptoms:

  • Intrusive memories or flashbacks

  • Hypervigilance

  • Exaggerated startle response

  • Emotional numbing and avoidance behaviors

  • Sleep disturbances

  • Irritability

Neurobiology of PTSD:

  • Amygdala:

    • Function: Overactive, leading to a strong fear response.

  • Hippocampus:

    • Function: Reduced volume, resulting in impaired memory and context regulation.

  • Medial Prefrontal Cortex:

    • Function: Underactive, causing weakened emotional regulation.

  • Anterior Cingulate Cortex & Insula:

    • Function: Altered, linked to emotional processing and threat detection.

Delayed Effects of Stress:

  • Definition: Refers to long-term psychological and physical problems that emerge after the initial stressor or trauma has passed. These effects can appear weeks, months, or even years later, compounding other health risks.

Types of Delayed Effects:

  1. Increased Vulnerability to Other Disorders:

    • Experience of PTSD or severe trauma increases likelihood of additional mental or physical health issues later in life.

    • Chronic stress can lead to anxiety, depression, or substance abuse if left untreated.

  2. Physical Health Problems:

    • Severe or prolonged stress can weaken the immune system, contributing to illnesses such as:

      • Heart Disease

      • Cancer

      • Diabetes

      • Ulcers

      • Sudden Cardiac Death

    • Linked to inflammatory diseases like:

      • Rheumatoid Arthritis

      • Lupus

      • Fibromyalgia

  3. Long-Term Health Effects from Chronic or Repeated Stress:

    • Prolonged exposure to high stress increases likelihood of chronic health conditions within as little as 6-7 years.

    • Example: High stress between 1994-1995 increased Canadians' risk of developing arthritis, bronchitis, ulcers, heart disease, and migraines six years later by 6% in men and 8% in women (Statistics Canada, 2004).

Manifestation of Delayed Effects of Stress:

  • Psychological Problems: Depression, anxiety, PTSD, substance abuse.

  • Physical Diseases: Heart disease, autoimmune disorders, inflammation.

  • Neurobiological Changes: Altered function in the amygdala, hippocampus, and prefrontal cortex.

  • Conclusion: Stress has both immediate and long-term effects on mental and physical health.

Physiological and Behavioural Mechanisms Linking Stress to Illness:

  • Stress contributes to illness through biological changes in the body and behavioral patterns that increase health risks.

Physiological Pathways:

  • Stress Hormones (especially cortisol and adrenaline):

    • Affect heart function, fat metabolism, and artery lining.

  • Consequences of Excess Stress:

    • Atherosclerosis (fatty blockages), hypertension, immune suppression, and inflammation.

    • Long-term activation of the HPA axis damages tissues and slows healing.

Behavioural Pathways:

  • Under stress, people are more likely to:

    • Smoke, drink, or overeat.

    • Lose sleep.

    • Skip medication or exercise.

    • Engage in risk-taking or social withdrawal.

Key Link:

  • Behavioural Changes + Physiological Arousal = Increased Risk for Chronic Disease.

  • Stress harms the body by:

    • Overactivating physiological systems (heart, immune, brain) and driving unhealthy behaviours,

    • Both increasing risk for chronic illness, infection, and early death.