Stress Flashcards
What is stress?
The body’s response to the challenge of a stressor
What is a stressor?
any stimuli that challenges the body’s homeostasis and triggers a response. It can be psychological, imaginative, physical or real.
What are considered major stressors?
death, natural disasters, war, divorce
What are considered minor stressors?
waiting in line/for the bus, traffic, daily hassles
Why did we evolve to have this stress response?
Most of the stressors that wild animals experience are short-lived and life or death situations/stressors. So, it makes sense for the stress response to be this intense.
Overall, what does the stress response do?
Uses all of the body’s energy to combat with the stressor and suspends any body repair, construction or growth to conserve energy.
What does the adrenal cortex produce?
Cortisol
What does the adrenal medulla produce?
Norepinephrine (noradrenaline) and epinephrine (adrenaline)
What does the sympatho-adrenomedullary axis (SAM axis) do in the end?
Causes the adrenal medulla to release epinephrine and norepinephrine (catecholamines) into the blood. This starts and mediates the “alarm stage” of GAS
What is cortisol?
A steroid hormone released by adrenal cortex and is part of the glucocorticoid family of hormones
What are the two main types of receptors that cortisol binds to?
Mineralcorticoid receptor (MR) & Glucocorticoid receptor (GR)
What effects does cortisol cause?
Metabolic effects (decrease in body mass, decrease in hunger, increases blood sugar levels, and decreases production of bone and connective tissue) and immune effects
How does stress impair cognition?
It suppresses higher level reasoning and flexible memory and thinking by deactivating the pre-frontal cortex and causing the older parts of the brain to become more dominant
Which brain structures work together to shut down the stress response?
Hippocampus, hypothalamus and anterior pituitary
What hormone does the hypothalamus and hippocampus aim to decrease?
corticotropin-releasing hormone (CRH)
What hormone does the anterior pituitary aim to decrease?
adrenocorticotropic hormone (ACTH)
What does allostatic load mean?
the cumulative burden of chronic stressors on the body.
What is eustress?
“positive stress”; experiences that are perceived as positive challenges rather than threats
What does the Yerkes-Dodson law propose?
Someone will reach their peak performance when they experience a moderate level/optimal level of stress or arousal. Too little or too much stress impairs performance.
