stress responses in human beings and physiology.ppt
- 1. PHYSIOLOGY OF STRESS Dr. Sandeep Kumar Raghuvanshi
- 2. STRESS What is stress? Pressures, demands (stressors), exert force on the body, stress is the body’s response to this. A stress response is an innate, defensive and adaptive reaction Stress levels also depend on whether the person feels that they can cope with demands placed on them or not
- 3. Stressors A stressor is a___ physical chemical biological agent environmental condition event causes stress to an organism or disturbances the homeostatsis
- 4. Homeostasis The process of maintaining a reasonable constant internal environment in the body • Temperature maintenance of body • 37ºC or 98.6 F
- 5. Acute vs. Chronic Stress • Acute stress • Sudden, typically short-lived, threatening event (e.g., robbery, giving a speech) • Chronic stress • Ongoing environmental demand (e.g., marietal conflict, work stress, personality)
- 6. PHYSIOLOGICAL SYSTEMS INVOLVED IN THE STRESS RESPONSE The nervous system The endocrine system The immune system
- 7. Nervous system Peripheral nervous system (PNS) Consists of all neural pathways to the extremities Triggered through the stimulation of sensory nerves Triggers a series of involuntary chemical response throughout the body Central nervous system (CNS) Brain and spinal cord
- 8. The Endocrine System The endocrine system is a network of four components: Glands Hormones Circulation Target organs Immune system T-cells found in the form of T-helper and T-suppressor
- 9. A decade of brain research •Repeated exposure to cortisol increases aging process of brain •Repeated exposure to cortisol damages/ shrinks brain tissue •Damage due to repeated exposure to cortisol appears to be irreversible •We are “wired for stress” for physical threats yet all threats set the alarm
- 10. How does stress cause physical illness? DIRECTLY INDIRECTLY SUPPRESSING THE IMMUNE SYSTEM Leucocytes (white blood cells) Lymphocytes (B Cells or T Cells) Anti bodies Natural killer cells Endorphins CARDIOVASCULAR DISORDERS Hypertension Strokes Changes in health practices that will increase risk of illness Smoking Drinking Drugs Sleeplessness Exercise less
- 11. Biopsychosocial Aspect of Stress • How stress affects health • Via behavior • Via physiology
- 12. Physiological Aspects • Cardiovascular reactivity – increased blood pressure, platelets, lipids (cholesterol) • Endocrine reactivity – increased catecholamines and corticosteroids • Immune reactivity – increased hormones impairs immune function
- 13. Behavioural Aspects • Increased alcohol intake • Smoking • Increased caffeine intake • Poor diet • Inattention leading to carelessness
- 14. Psychophysiological Disorders • Digestive system – e.g., ulcers, irritable bowel syndrome • Respiratory system – e.g., asthma • Cardiovascular system – e.g., hypertension, lipid disorders, heart attack, angina
- 15. How to survive? 1) Remove the STRESSOR! 2) EFFECTIVELY Cope with the STRESSOR!
- 16. Thanks