Overview
This lecture covered the body's stress response, its physiological effects, key terminology, associated health problems, and strategies for coping with stress.
Stress Response and Homeostasis
- Stress disrupts homeostasis, the body's process of maintaining internal balance.
- A stressor is any factor causing significant bodily change (emotional, physical, etc.).
- The stress response is also known as the "fight or flight" response, increasing heart rate, blood flow, and alertness.
- Severe or prolonged stress increases tissue wear and depletes metabolic resources, worsening chronic conditions.
General Adaptation Syndrome (GAS)
- GAS describes three stages: alarm (mobilization of defenses), resistance (peak performance), and final/cooldown (recovery or system failure).
- In the alarm stage, the hypothalamus, nervous system, and adrenal glands trigger hormone release (norepinephrine, epinephrine).
- Resistance stage maintains heightened bodily function; final stage involves recovery or potential harm if stress persists.
Physiological Effects of Stress
- Stress increases blood pressure, heart rate, bronchodilation (open airways), and blood glucose.
- Non-essential processes (inflammatory and immune responses) are suppressed during stress.
- After stress, fatigue and delayed pain/inflammation often occur.
Positive and Negative Stress
- Positive stress (eustress) increases motivation and creativity.
- Negative stress (distress) causes harmful effects like increased heart rate and suppressed immunity.
Health Problems Associated with Stress
- Stress can cause headaches, mouth ulcers, gum disease, reduced blood flow to organs, and impaired GI and kidney function.
- Prolonged stress can result in renal failure (due to vasoconstriction), stress ulcers, infections, and slow healing.
- Chronic stress can lead to or worsen psychological conditions like PTSD.
Coping with Stress
- Coping strategies include rest, healthy diet, exercise, counseling, and relaxation techniques (e.g., deep breathing).
- Engaging in enjoyable or distracting activities aids stress relief.
Key Terms & Definitions
- Stressor — Any factor causing significant change or stress in the body.
- Homeostasis — The body's process of maintaining a stable internal environment.
- General Adaptation Syndrome (GAS) — The three-stage physiological response to stress: alarm, resistance, final stage.
- Eustress — Positive, motivating stress.
- Distress — Negative, harmful stress.
- Catecholamines — Hormones (norepinephrine, epinephrine) released during stress.
Action Items / Next Steps
- Review textbook Chapter 26 (page 615) on stress and associated problems.
- Practice deep breathing or relaxation exercises before exams.
- Identify personal stressors and apply coping strategies discussed.