Stress and Health

Question 1

contrast allostasis vs allostatic overload

Answer 1

• allostasis: the process of maintaining stability (homeostasis)
• allostatic overload: the wear and tear on the body and brain caused chronically increased allostasis

Question 2

describe Yerkes-Dodson law and the 2 corollaries

Answer 2

• performance and adaptive learning are optimal under moderate levels of stress
• corollary 1: learning new or difficult tasks is optimal with low/moderate arousal levels
• corollary 2: performance of well-learned tasks is optimal with moderate/high arousal levels

Question 3

describe dysregulation of HPA

Answer 3

• abnormal cortisol levels found in:
  
  • anxiety disorders (high cortisol)
  • depression (high cortisol)
  • PTSD (high and low cortisol)
  • history of child abuse (high cortisol)
  • professional burnout (high cortisol)

Question 4

describe individual differences in genetics in stress response

Answer 4

• genetics (nature)
  
  • genotypic variations in HPA afferents are associated with specific personality types and regulate HPA response to psychological and physiological stressors
  • shorter form of the serotonin transporter is associated with increased stress response and vulnerability to depression and alcoholism

Question 5

describe individual differences in nurturing that affect stress response

Answer 5

• early experiences can “hard-wire” the stress-response (modeling, secure attachment)
• greatest learning occurs in first 9 months
• early trauma/abuse (risk factor)
• uncertainty in food supply (risk factor)
• novelty/enriched environment (protective factor)

Question 6

describe the 3 stages of adaptation to stress

Answer 6

• alarm stage: organism’s adaptive responses are mobilized
• resistance stage: organism attempts to cope by utilizing available resources
  
  • organism is in a state of immunocompromise
• exhaustion stage: demand exceeds available resources and defensive efforts fail, and the individual becomes increasingly susceptible to disease

Question 7

describe the 4 types of allostatic loads

Answer 7

• repeated hits from multiple stressors
• lack of adaptation
• prolonged response due to delayed shut down
• inadequate response that leads to compensatory hyperactivity of other mediators

Question 8

describe how stress affects the immune system

Answer 8

• acute stress activates the immune system
• chronic stress is associated with immunosuppression
  
  • excess glucocorticoids in blood impairs production of natural killer T cells and B cells
  • reduced antibodies
• paradoxically, chronic stress can also lead to heightened autoimmune response (body attacks itself): MS, RA, juvenile diabetes, allergies

Question 9

describe how stress can affect metabolism

Answer 9

• excess glucocorticoids results from chronic stress and can impair cellular response to insulin
  
  • increased glucose and fat in the bloodstream
  • decreased O2 flow and organ efficiency
• chronic stress induced hyperinsulinemia is associated with T2D, coronary artery disease and metabolic syndrome

Question 10

describe how stress can affect reproduction

Answer 10

• excess glucocorticoids inhibit hypothalamic release of:
  
  • LH
  • FSH
  • testosterone
  • progesterone, estrogen and egg production
• stress impairs PS activation needed for erection
• decreased progesterone can lead to osteoperosis and impaired uterine wall nutrition (miscarriage, preterm labor)