Health Consequences of Dys. Stress Flashcards
Bidirectional relationship between mental and physical health
1) Emotional appraisals and coping strategies alter physical effects of stress
2) Importance of Personality variables:
* Type A personality —> exaggerated reactivity —> increased cardiovascular disease
* Neurotic personality traits —> poor stress regulation
3) Anxiety/depression co-occur with many physical health conditions :
* Worse physical health with more severe forms of anxiety/depression
4) Inflammation is both a cause and effect of anxiety/depression:
* Effective anti-depressants improve mental health and reduce inflammation
5) Health conditions worsen with poor health care choices:
* Use of drugs/alcohol
* Poor diet/Lack of exercise
Glucocorticoid Cascade Hypothesis
1) Health consequences get more severe at older ages
2) High levels of stress (elevated cortisol) combine with other health concerns:
* i.e. Reduced oxygen or reduced glucose in blood
* Internal organs less to adapt with increasing age
3) Hippocampus lacks energy resources to downregulate HPA
4) Neurons in hippocampus die, further weakening regulation of HPA
5) Cortisol levels increase, further stressing the internal organs
6) The negative health effect accumulate over time, which contributes to premature aging and worsens any other health issues
Depression, Anxiety, and Inflammation linked to
Depression, Anxiety, and Inflammation linked to cellular aging
1) Telomere shortening:
* Telomeres are caps at the end of chromosomes
* Telomeres get shorter each time a cell divides
2) Depression, anxiety, and chronic inflammation linked to more rapid telomere shortening:
* Cells are getting older at a faster rate
* Thus, the internal organs are too.
Allost Load? parasym. func.? Gluco. Cas. Hypot.? Telomere shorteni?
Chronic stress is associated with more?
More sickness and death….
1) Allostatic Load:
* Stress places “wear and tear” on the body
* Alters immune functioning. Increased inflammation
2) Reduced parasympathetic functioning:
* Slower stress recovery
* Prolonged inflammatory responses
* Reduced ability to repair physical injury
3) Glucocorticoid Cascade Hypothesis:
* Damaging effects of stress accumulate with age
* Aging impairs ability to regulate HPA functioning
4) Telomere Shortening:
* Evidence of rapid aging at the cellular level
Chronic stress is associated with a wide range of “metabolic diseases”. What are they?
1) Cardiovascular Disease (CVD):
* High blood pressure
* Clogged/hardened blood vessels
* Weakened or oversized heart muscle
2) Type-2 Diabetes:
* Dysregulation of body’s energy needs
* Body becomes resistant to insulin
* Results in too much sugar in the blood
3) Polycystic Ovarian Syndrome (PCOS):
* Common cause of female infertility
* Endocrine dysfunction
* Affects reproductive, cardiovascular, digestive, and renal systems
Microbiome?
- Populations of bacteria and other microbes living in (and on) your body.
- Plays important role in maintaining health and immune functioning.
Eubiosis
- Mutually beneficial relationship between microbiome and host.
- More “good” microbes than “bad” ones.
- Reduced inflammation. Better immune functioning.
Dysbiosis
- Unbalanced relationship between microbiome and host.
- Can be caused by stress.
- Too many “bad” microbes. May lead to disease state.
- Gastrointestinal disease (i.e. Irritable Bowel Syndrome) linked to dysbiosis.
- Fecal Transplants as a medical treatment (Restores the microbiome by transplanting fecal matter from a healthy donor).
Stress, Aging, and Obesity
1) Stress increases desire for high energy foods (fats and sugars):
* Cortisol regulates the body’s energy stores
* Releases stored energy to respond to stressors
* And… increases motivation to replace energy stores
2) Chronic stress and aging contribute to weight gain:
* Eat more high energy foods. (lots of calories)
* Poor diet and stress disrupts microbiome
* Metabolic changes with age. Less efficient at burning calories
* Weight increases while physical activity decreases
3) Weight gain can worsen physical and mental health:
* Correlations between obesity and depression
Interaction of HPA axis with reward systems?
2) Interaction of HPA axis with reward systems:
* Behaviors linked to stress is also driven by reward systems
* Release of ACTH also causes release of beta-endorphin
* A “fearful” response can also be a “rewarding” one
* Can’t assume that cortisol reactivity is consistently linked to aversive feelings
* Risky behaviors can be both frightening and pleasurable (i.e. sky diving)
3) May seek different forms of “drug” as way of coping with dysregulated stress:
* “Drug” could include other types of addictive behavior
Kabbaj et al (2000) Light-Dark Box paradigm
1) Kabbaj et al (2000):
* Rat model of “sensation seeking”
* Study of rats’ exploration of a novel environment
2) Light-Dark Box paradigm:
* By default, rats prefer a dark environment
* For a rat it’s safer in the dark
* “Light-Dark” box has two sides:
a) One is dark and enclosed
b) The other is open and exposed to light
* When placed in a light-dark box, rats first move to the dark side
* BUT…. Eventually… they will want to explore the other side
Two patterns of rat’s behavior (Into the Light)
Two patterns of behavior:
1) High-responding rats (HR) - Faster to explore the light side.
2) Low-responding rats (LR) - Slower to explore the light.
Corticosterone release:
* HR rats show more corticosterone reactivity
* LR rats show less corticosterone reactivity
BUT… HR rats also show bigger dopamine release:
* Dopamine involved in reward and reinforcement
The HR rats may possibly find the increased risk and stress more “rewarding ”
* Or at least more “worth it”
The dark side of the light: High responding rats (HR)
1) High responding rats (HR):
* Were faster to explore the “light side” of the box
* Showed more corticosterone reactivity
* And more dopamine release in response to the stressor (The novel environment is the stressor)
2) But… HR rats were also faster to get addicted to cocaine:
* In these studies, the rats could self-administer cocaine
* Press a button get some cocaine infused into the brain
* HR rats used more cocaine from the start and became addicted more quickly
Operant conditioning? Positive vs Negative reinforcement & punishment
Operant conditioning
* Learned association between a behavior and an outcome for the behavior.
Behaviors with reinforcing outcomes increase:
* Positive reinforcement = got something good
* Negative reinforcement = avoided something bad
Behaviors with punishing outcomes decrease:
* Positive punishment = got something bad
* Negative punishment = lost something good (take smth away)
Addictions develop through combination of?
1) Addictions develop through combination of positive and negative reinforcement
2) Initial drug use (or other additive behavior) motivated by positive reinforcement:
* Drug feels good, gambling is fun, food is yummy
* “Impulsive” behavior —> Do it because you want to
3) Later drug use (or other addictive behavior) motivated by negative reinforcement:
* Need the drug to feel normal
* Need to gamble, eat, shop, etc… to get rid of bad feelings
* “Compulsive” behavior –> Do it because you have to
