Lecture 34: Stress

Question 1

***what does homeostasis mean?

Answer 1

Homeo=same / stasis=not changing

Homeostasis means the maintenance of a constant internal environment.

system of biological organism and is not equilibrium because it requires energy to do so

stress- expand energy to maintain homeostasis

Question 2

***what does distress mean?

Answer 2

persistent or chronic stress that is not resolved through coping or adaptation

severe, protected, uncontrollable experience with stress
leads to chronic distress

Question 3

***what does eustress mean?

Answer 3

good stress
stress that enables us to grow
stress that enhances function

mild brief, controllable, experience with stress
perceived as pleasant, enables growth

Question 4

***what is fast response?

Answer 4

autonomic activation.

when you perceive a stess you can feel the autonomic arousal
cause physiological arousal: pupils dilating, breathing goes up

Question 5

***what is HPA axis, and how is it regulated?

Answer 5

Hypothalamic-pituitary-adrenal

Monoamine regulates HPA axis I.e. Dopamine, serotonin, and norepinephrine

Oxytocin suppress HPA axis

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regulation:
hypothalamus regulates it

prolonged stress and release of cortisol causes shrinkage of the hippocampus
and because of this you have decrease ability to regulate the stress axis - DMX (dexamethasone) analogue of cortisol

Question 6

***How is HPA axis activity altered in depression?

Answer 6

DMX (dexamethasone) analogue of cortisol

• depressed people lose the ability to regulate cortisol in their blood

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Patients with depression may have elevated cortisol in plasma and cerebrospinal fluid and increased levels of CRF messenger RNA and protein in limbic brain regions. Sensitivity of the hypothalamus to feedback signals for the shutdown of CRF release is about half in severely depressed patients. Disturbances in the function of the HPA axis in depression cause cortisol levels to spike erratically throughout the day.