Stress

Question 1

There is the CNS and PNS. Within the PNS there is the Autonomic and Somatic NS . What are the components of each?

Answer 1

Autonomic consists of motor/sensory neurons

Somatic NS consists of the sympathetic and the parasympathetic NS

Question 2

What is the parasympathetic NS and what is it responsible for?

Answer 2

Parasympathetic NS is responsible for rest and digest
Once the stressor has passed, it bring body back to homeostasis- its balanced state.

Question 3

What is the sympathetic NS and what is it responsible for?

Answer 3

Sympathetic NS is responsible for flight or fight response
Gives your body burst of energy when you detect a threat.

Question 4

!!Explain the pathway of stress response in the sympathetic NS. Name the different parts of the brain involved in this pathway

Answer 4

Stressor –> alerts amygdala –> hypothalamus –> pituitary gland –> adrenal glands –> bloodstream/body

Question 5

What are some physiological responses during the flight or fight stress response?

Answer 5

Increased heart rate (pump more blood/oxygen to the brain for decisions)
Shutting/slowing non essential systems eg digestion
Relaxing/expanding brochi to get more oxygen in body per breath

Question 6

What is the likely function of the fight or flight response ?

Answer 6

Evoluntionary perspective is that it was to run from predators, escape danger. but now it is activated during emotional/psychological threats/stress

Question 7

What is the function of the HPA axis? Which body parts are involved and what hormones do they release?

Answer 7

Hypothalamus
Pituitary glands
Adrenal glands

The HPA axis is a neuroendocrine system in the body that helps regulate stress response and various physiological processes. Its main function is to maintain homeostasis, or balance, in response to stressors.

Question 8

What are the physiological changes during rest and digest/ parasympathetic NS kicking in? When and why does it do so?

Answer 8

Lower heart rate
Re activate other bodily functions/systems

Question 9

!!What is the Transactional Model of Stress? What is the primary and secondary appraisal?

Answer 9

The transactional model of stress suggests that stress is not simply a response or a stimulus, but rather a result of an individual’s interaction with their environment.
The primary appraisal is the initial perception a person will have this stimuli - is it a threat? Harmful? A challenge?
Secondary appraisal is whether a person then believes to have the resources to cope with the stressor. How will i deal with the situation - CAN I deal with it
Its a dynamic procees of appraisal and reappraisal

Question 10

How does control affect our appraisal of stress?

Answer 10

The more perceieved control, the less the stress related regions (such as anterior insula) will fire
Shows that our appraisal of a stressor will affect our brain responses

Question 11

What are the physiological impacts of acute stress on the PFC and amygdala? What kind of tasks will this affect?

Answer 11

Acute stress impairs the PFC (top down thinking, working memory, flexible thinking)
It enhances the hippocampal and amygdala function and acute stress tends to improve the performance of simple, well rehearsed tasks

Question 12

The control of behaviour and emotion usually takes place in … but switches to … brain circuits in acute stress situations:

Answer 12

Usually takes place in PFC but switches to more primitive brain circuits (brainstem, limbic system) during times of stress

Question 13

Describe the PFC control in normal times/ periods without stress?

Answer 13

PFC is in control
Orchestrate brain activity for intelligence regluation of behaviour thought and emotion

Question 14

Describe the amygdala control during times of stress

Answer 14

Stress makes PFC control impaired, which strengthens amygdala functions
Attention switching from top down to bottom up

Question 15

What effects does chronic stress have on neurons of the PFC and amygdala?

Answer 15

PFC dendrite length become shorter
In amygdala the dendrite length increases–> remodelling of neurons may lead to mainffestaitons of enhance emotionality under chronic stress

Question 16

What is allostatic load and how does exposure to stress affect it?

Answer 16

Wear and tear effects on the body because of long term continued exposure to stress
Short term stress promotes adaptation (allostatisis) but long term

Question 17

Short term stress vs chronic stress effects on immune system

Answer 17

Short term stress enhances immune function, as an adaptive measure to deal with stressors in the environment but when chronic stress, immune system is suppressed

Question 18

What is the effect of chronic stress on memory? Which type of memory does it affect? What is the physiology behind it?

Answer 18

It affects prospective memory the most
Chronic stress –> Cortisol binds to hippocampus (area critical for prospectve memroy) which alters the hippcampal functional connectivity

Question 19

What is PTSD and its symptoms?

Answer 19

Post traumatic stress disorder
Symptoms include
re experiencing
hyper arousal (nightmates, exaggerated responses to certain stimulis..)
Avoidance behaviour (avoiding people, experiences that even remotely reminds them traumatic experience)

Question 20

What is the relaitonship between PTSD and amygdala?

Answer 20

Patients with PTSD had a higher activation of the amygdala

Question 21

What is the relationship between PTSD and the hippocampus?

Answer 21

Patients with PTSD tend to have smaller hippocampal volume. But is this a risk factor or a result of PTSD

Question 22

What do studies suggest about hippocampal volume and PTSD- risk factor or result?

Answer 22

Twiin studies suggest that a smaller hippcampus is a risk factor- it us a ore exisitng condition that may make the brain more vulnerable to developing patholgical stress repsoinses.
Even when traumatic experience has been dealt with, there is no hippocampal growth