Physical vs. Psychological Stress

Question 1

Examples of Physical vs Psychological Stress

Answer 1

Examples of Physical Stress
* Exercise
* Fight-or- flight sympathetic activation
Examples of Psychological Stress
* Mental math
* Social stress
* Psychomotor tasks
* Reaction times, eye hand coordination
* Getting stressed out while playing video game would be psychomotor.

Question 2

The Painstation

Answer 2

Example of Psychomotor Stress
The Painstation
* A version of the classic game Pong
* Rigged to cause pain to the players when the other person scores.
Multiple pain methods:
* Shocks
* Heat
* Even a built-in hand whip

Question 3

Classes of Stress Response

Answer 3

• Bottom-up vs. Top-Down
• Activation (High vs. Low)
• Valence (Appetitive vs. Aversive)

Question 4

Bottom-up vs. Top-Down Stress Response

Answer 4

Physical stress –> more bottom-up
* Physically demanding on the body. Signal sent from the body up to the brain.
Psychological stress –> more top-down
* Mentally demanding. Signals sent down from the brain to the body.

Question 5

Valence (Appetitive vs. Aversive) Stress Response

Answer 5

1) Appetitive activation may be enjoyable even if metabolic (biochemical processes that occur within us) demands are high.
* Sexual arousal, eager anticipation.
2) Aversive activations are unpleasant. May cause more distress even if overall physiological demands are low.
* Public speaking anxiety, relationship loss

Question 6

Emotions often classified by two main components:

Answer 6

Valence
* Positive vs. Negative
* Pleasant vs. Unpleasant
* Appetitive vs. Aversive
Activation/Arousal
* High energy vs. Low energy
* Expend energy vs. Conserve energy

Question 7

The Exercise Response

Answer 7

1) Primarily physical, but still includes psychological components.
2) Exercise response requires changes in physical homoeostasis:
* To maximize amount of oxygen and fuel available to muscles
* “Bottom-up” influences
* Changes in cardiac out, blood pressure, breathing, hormone levels, water and electrolyte balance
* Activates sympathetic nervous system
3) Influenced by top-down components
* Preparation, motivation, emotional state

Question 8

What are the changes in physiology that occur in preparation for exercise?

Answer 8

Begins in Higher brain areas
* Prefrontal cortex —> supplementary motor cortex —> premotor cortex —> motor cortex
Alters activity of hypothalamus and brainstem
* Increased sympathetic activity. Suppression of parasympathetic activity.
* Increased heart rate, cardiac output, blood flow to muscles
Example: Increased heart rates in runners preparing for a race
* Increases in heart rate proportional to the anticipated effort required
* Bigger heart rate increases for sprinters than long-distance runners

Question 9

Active Phase of Exercise?

Answer 9

Muscle activity increases physiological demands
Sensory nerves detect muscular contractions and signal CNS
Substantial and prolonged increase in blood flow
* Up to a 600% increase from resting state
* Increased cardiac output to body
* Increased blood return from the body
* Frank-Sterling Reflex: Heart pumps harder, when volume of blood is increased
Endocrine activity:
* Epinephrine/Adrenaline
* Cortisol
* Beta-endorphin

Question 10

Endocrine changes during exercise

Answer 10

Epinephrine/Adrenaline
* Increase force of heart contractions. Dilate blood vessels
* Release stored fat to be turned to energy
Cortisol
* Release stored fats and glucose to be turned into energy
* Aids conversion of proteins into glucose
Beta-endorphin
* Released from pituitary gland with ACTH release in about equal amounts.
* Beta-endorphin and ACTH made from same precursor molecule.
* Reduce pain and discomfort from exercise.
* May promote positive mood. Reduce negative emotions.

Question 11

Preparation for Exercise vs. Active Exercise

Answer 11

Preparation for Exercise
1) Primarily top-down
2) Increased blood pressure:
- Increased cardiac output
- Increase vasoconstriction
- Heart pumps harder, but the blood vessels are narrowed
Active Exercise:
1) Primarily bottom-up
2) Increased blood pressure:
* Increase cardiac output
* Increased blood return to the heart
* Increased vasodilation (widening of blood vessels)
* Heart pumps harder, but the blood vessels are more relaxed

Question 12

Why is Exercise Good For You?

Answer 12

• Exercise is a stressor
• The body responds to cope with stressors
• Body can adapt to repeated exposure to a stressor
• Exercise can promote health and increase physical capacity when… :
  1) Voluntary and meant to promote positive outcomes
  2) Sufficient recovery time and resources
  But, overtraining can be detrimental
• Push body beyond it’s capacity to recovery
• Elevated cortisol levels and negative emotions

Question 13

The Runner’s High?

Answer 13

• Described as a feeling of euphoria that long-distance runners can experience.
• Occurs after prolonged and sustained exercise.
• Prolonged effort, but not total overexertion.
• Related to elevated levels of endogenous opioids (like beta-endorphin).
• Endogenous opioids released from pituitary and specialized neurons.
• May also be related to increased levels of endocannabinoids.

Question 14

The Fight or Flight Response

Answer 14

1) Fight or flight responses cause similar affects as exercise
2) Endocrine changes
* Epinephrine, Cortisol, Beta-endorphin
* Free up stored forms of energy
* Promote strength and vigor of physical reactions
3) Autonomic changes
* Enhance sympathetic activity
* Suppress parasympathetic activity
* Use energy, don’t conserve energy

Question 15

“Fight-or-flight” refers to a prototypical stress response

Answer 15

• Tied to evolutionary drives for survival. Fight or flee a threat.
• Requires the same physiological and neuroendocrine changes as exercise.
• But… also prototypically very aversive (highly negative).
  High activation:
• Requires substantial metabolic change
  Highly aversive:
• Associated with negative emotions (Anxiety, Fear, Anger)
• Limited control/High stakes
  Fight or flight for survival.
  Your efforts may fail. And if you fail, you die.

Question 16

Importance of Valence

Answer 16

Physical exercise and the fight-or-flight response have similar bottom-up components:
* High activation
* Burns energy.
But… very different top-down components:
* Exercise is appetitive: voluntary, linked to positive emotions, and positive outcomes.
* Fight or flight is aversive: involuntary, linked to negative emotions, and may have disastrous outcomes.
The aversive nature of fight-or-flight responses increases the intensity of physiological response:
* Even if physical requirements are the same, greater allostatic load if the experience is aversive.

Question 17

Psychological Stressors

Answer 17

Psychological stressors:
* No risk of physical injury.
* But, still threatening to the individual.
* Can arose physiological responses.

Common psychological stressors:
* Social loss or rejection
* Failure to achieve a goal
* Anxiety or anticipation of a negative event
* Cognitive and attentional overload
* Doing math in your head.

Question 17

Aversive vs. Appetitive Responses

Answer 17

Study of Physiological Responses to Aversive and Appetitive Outcomes.
Study 1: Aversive outcomes:
* Complete psychomotor task to avoid receiving aversive stimuli.
* Must press a button to avoid unpleasant noise and electric shocks.
* Task was unpredictable and some noise and shocks were unavoidable.
Study 2: Appetitive outcomes:
* Complete psychomotor task to earn money.
* Task was unpredictable, but outcomes were positive (earned money).

The tasks are physically similar and require very little metabolic energy:
* Completed while sitting in a reclining chair

Question 18

Physiological effects of mental math

Answer 18

Physiological effects of mental math:
* Decreased vagal tone (decreased parasympathetic activity).
* Increased sympathetic activity.
* Increased heart rate and contractility (heart speeds up and pumps harder).
* Vasoconstriction may increase (Increasing blood pressure).
* Increased cortisol.

Increasing the difficulty of the mental math, increased physical response:
* More difficult = more aversive

Question 18

Aversive vs Appetitive Outcomes

Answer 18

Study 1: Aversive Outcomes (Noise and Shock)
* Physiological outcomes similar to fight-or-flight.
* Increased blood flow:
1) Heart pumps faster and harder
2)Blood vessels dilated
* Increased blood pressure
* Increased norepinephrine (increase in sympathetic activation)
* Increased cortisol
* Increased subjective emotional distress
Study 2: Appetitive Outcomes (Monetary Rewards)
* Required similar levels of effort and attention as Study 1
* Similar cardiac and endocrine responses etc.
* BUT…. No significant increase in cortisol

Question 18

Mental Stress vs. Emotional Distress

Answer 18

1) Psychological stress has physiological and neuroendocrine effects.
2) Mental effort required in both appetitive and aversive tasks, similar patterns of cardiovascular and endocrine activity:
* Increased blood flow
* Increased blood pressure
* Increased sympathetic activation (via norepinephrine)
3) But… levels of cortisol increase associated with levels of aversion (when smth feels bad).
* More aversive and distressing tasks lead to proportional increases in cortisol.

Question 19

Stress vs. Distress

Answer 19

1) Mental activity alone can cause significant physiological changes.
* Physiological changes can occur absent of immediate physical demands.
2) Physical stress need not involve emotional distress.
3) Emotionally positive, negative, and neutral states may elicit similar and overlapping physiological effects.
* Falling in love, fighting for your life, or running a marathon.
* Similar cardiovascular and endocrine responses.
4) Greatest distinction between physical stress and emotional distress involves cortisol response
* Increased cortisol with increased negative emotions