Introduction to Stress - Nakajima

Question 1

What is the definition of stress?

Answer 1

Stimulus (stressor), Response (strain), and Process (interactions between the two)

“A physical or emotional factor that causes bodily or mental tension, and may lead to disease causation”

“A negative emotional experience accompanied by biochemical, physiological, cognitive, and behavioral changes that are directed toward altering the stressful event”

Question 2

What is the difference between physical and physiological stress?

Answer 2

Physical stress: a direct physical threat to one’s well-being
Cold, heat, infection, extended exercise etc.
-Bottom => Up process

Psychological stress: an event that is ‘perceived’ as negative (not physically threatening), Top => bottom process

• Loss of a loved one
• Major personal disappointment
• Unemployment

Question 3

What are some important theoretical contributions to the study of stress?

Answer 3

-Homeostasis: the collective process of maintaining the internal physiological stability in the face of environmental change.
-Allostasis (active refinement of homeostasis): the compensation that an organism engages in to achieve homeostasis successfully.
-The fight-flight response incorporates powerful emotional (anxiety, fear, anger), neuroendocrine and autonomic changes to increase chance of survival.
-General Adaptation Syndrome (GAS)
…Alarm reaction, where the body detects the external stimulus
…Adaptation, where the body engages in defensive countermeasures against the stressor
…Exhaustion, where the body begins to run out of defenses (results from long-term exposure to the stress)
-Coping: the process of managing demands that are appraised as taxing or exceeding the resources of the person.

Question 4

What are the physiologic mechanisms of stress?

Answer 4

1) Sympathetic-Adrenal-Medulla (SAM) axis (catecholamines)

2) Hypothalamus-Pituitary-Adrenal (HPA) axis (via corticotropin-releasing hormone (CRH) and ACTH)

Question 5

How does cortisol influence the immune system?

Answer 5

Cortisol can inhibit immune functions in several ways including:

• Decreased macrophage response to IL-2 or interferon-gamma
• Decreased macrophage cell ingestion
• Decreased IL-1 production by macrophages
• Decreased IL-2 production by T cells
• Decreased production of CD4 cells
• Suppressed activity of B lymphocytes
• Decreased activity of NK cells

Question 6

What are some Coping Behavioral Techniques?

Answer 6

Relaxation
Cognitive strategies
Stress inoculation
Exercise
Social support
Pharmacological interventions
Biofeedback

Question 7

How is chronic activation of HPA system associated with the development of cardiovascular diseases?

Answer 7

• The combination of cortisol and cholesterol diet for 52 weeks produced significant atherosclerotic injuries in the aortic intimal surface in monkeys.
• There is a positive association between plasma levels of cortisol and early atherosclerosis in humans as documented by coronary angiography.