Lecture 6: Stress Flashcards
(21 cards)
What is the physiology of stress?
- The nervous system
- The endocrine system
- The immune system
What is the role of the autonomic nervous system?
Parasympathetic is rest and digest, which results in the release of acetylcholine. It calms the body down. Sympathetic is the release of catecholamines: epinephrine (adrenaline) and norepinephrine (noradrenaline). It is fight or flight mode
What is the role of the sympathetic nervous system?
Releases epinephrine/adrenaline and norepinephrine and noradrenaline. They are responsibly for physical readiness to stress (increased heart rate and blood pressure, vasodilation or arteries through working muscles, dilation of pupils, reduction of digestive activity). Involved in catabolic functioning (complex molecules are broken down for energy)
What is the role of the parasympathetic nervous system?
Releases acetylcholine (which reduces heart rate and muscle tension). Responsible for anabolic functioning (various body cells regenerate or grow like muscle tissue)
How to measure ANS?
Electrodermal activity: Skin conductance level/response. Cardiovascular activity: heart rate (ECG/EKG), blood pressure, blood volume (plethysmography)
Endocrine system
Endocrine glands → production of hormones
Main glands responsible for stress response:
Pituitary gland (“master gland”)
Hypothalamus
Adrenal glands
Production of Glucocorticoids (steroids that influence the metabolism rates of proteins, fats, and sugars/glucose)
What is the role of the Hypothalamic-Pituitary Adrenal Axis?
Cortisol (main glucocorticoid) increase
Helps to generate glucose through the degradation of amino acids → Increase of blood sugar (gluconeogenesis)
Breaks down fats for energy (lipolysis)
Effects on the immune system: Reduction of immune responses and limitation of inflammatory responses, metabolizes white blood cells
Symptoms of high cortisol levels?
- weight gain
- puffy/flushed face
- mood swings
- increased anxiety
- higher susceptibility to infection
- high blood pressure
- acne or other skin changes
- higher risk for bone fractures and osteoporosis
How does cortisol fluctuate?
- cortisol increases in the morning-> cortisol awakening response (difference btw cortisol levels at waking and 30 mins after waking)
What is the immune system made up of?
Innate (natural) system: general inflammation response
Adaptive system: slower, cellular response is viruses and humoral response is parasites & bacteria
What are the effects of stress?
Acute time-limited stressors like experimental manipulation: innate system increases while the adaptive system decreases
Brief naturalistic stressors like an exam: innate system increases while adaptive system decreases
Chronic stressors: innate system and adaptive system decrease
Stress
The nonspecific response of the body to a demand
Distress
When demands result in unpleasant conditions
Eustress
When demands result in pleasant conditions
General Adaptation Syndrome Model
- Alarm reaction (with general physiological stress response)
- Resistance stage (body diminished the effects of the alarm reaction)
- Prolonged exposure to stressor → exhaustion
Problems:
* Simple, non-specific stress model
* Does not explain the variety in physiological responses depending on different stressors, contexts, and individuals
Allostatic load
Conceptualization of stress and physiology. Allostasis is stability through change, and homeostasis is created through allostasis. Includes physiological systems that respond to environmental demands and anticipated demands and the adjustment of these systems. There can be symptoms of pathology caused by a chronic allostatic state with cumulative effects of stress responses due to chronic stress. Measured through composite index of biomarkers like neuroendocrine, cardiovascular, immune and metabolic
Transactional stress model
Stress is subjective and cognitively determined. There is an emphasis on the primary appraisal of stressors and secondary appraisal (analysis of available resources) and coping (overcoming of stress). Criticism: emphasis on cognitive processing as affective processes may occur without cognition
Can work stress may you sick?
Stressors like: interpersonal conflict, lack of control, organizational constraints, role ambiguity, role conflict, working hours and workload
Physical health: back pain, eye strain, appetite, headaches, sleep problems, fatigue, dizziness, gastrointestinal problems
Which stressors have the strongest relationships?
Interpersonal conflict, organizational constraints, role conflict and workload. These relationships other than org constraints are smaller in longitudinal designs. Lack of control is significantly larger in longitudinal designs. Interpersonal conflict has a significantly larger association with sleep disturbances than with other symptoms. Organizational constraints have a significantly larger association with fatigue and gastrointestinal problems than other symptoms. Workload has significantly larger associations with eye strain and fatigue
What is the role of ACTH and SNS agonists?
They slowed down digestion and upset stomach as fast reactions to stressors
What is the relationship between organizational stressors and physical health outcomes?
Occupational stressors are differentially related to individual strains
Interpersonal conflict, organizational constraints, and workload are associated with all physical health outcomes
However, the strengths of the associations vary
None of the symptoms correlated with all stressors
Gastrointestinal problems and sleep disturbances were related to more stressors than the other symptoms
