PSYCH U3 AOS 1 - NERVOUS SYSTEM AND STRESS

Question 1

What is the role of the human nervous system?

Answer 1

To enable the brain to obtain information about the exernal and internal environment and response appropriately.

It RECIEVES information, PROCESSES information, and CO-ORDINATES a response to information.

Question 2

What is the central nervous system? What are the roles of its divisions?

Answer 2

The CNS is made up of the brain and spinal cord and its main role is to process information received from the body’s internal and external environment and activate appropriate responses.

BRAIN: Processes information from neural pathways and directs actions in the body. Constantly recieves information from the outside world via senses and responds by controlling all bodily functions and actions.

SPINAL CORD: recieves sensory information from the body via the PNS and sends to brain (afferent messages), and recieves motorr information from the brain and sends to relevant parts of the body to control all muscles, organs, and glands (efferent)

Question 3

What is the role of the peripheral nervous system?

Answer 3

To carry information TO the CNS from sensory receptors and internal muscles, organs, and glands
To carry information FROM the CNS to the body’s muscles, organs, and glands.

Divided into Somatic and Autonomic nervous system

Question 4

What is the role of the peripheral nervous system?

Answer 4

To carry information TO the CNS from sensory receptors and internal muscles, organs, and glands
To carry information FROM the CNS to the body’s muscles, organs, and glands.

Question 5

What is the role of the somatic nervous system?

Answer 5

Transmit sensory afferent information from the sensory receptor sites to the CNS where sensory neurons will communicate it to interneurons
AND
Transmit motor information from the CNS along motor efferent pathways to skeletal muscles to control movements

Controls all VOLUNTARY movements

Question 6

What is the role of the autonomic nervous system?

Answer 6

To connect the CNS to the bodies internal (visceral) muscles, organs and glands and provide feedback to the brain about their activity.

Controls visceral muscles that have built in mechanisms and don’t depend on concious effort of the brain.
Regulates INVOLUNTARY/UNCONCIOUS functions like breathing, digestion, heart rate.

Question 7

What is the role of the sympathetic nervous system?

Answer 7

Activates the body’s internal muscles, organs, and glands to prepare the body for vigorous activity or a stressful situation in order to enhance survival.
EG. increases heart rate and respiration rate so body gets more energy, or release adrenaline, and decreases unneccessary functions like salivation and digestion so as to save energy.

Question 8

What is the role of the parasympathetic nervous system?

Answer 8

counter balances the sympathetic nervous system. In times of minimal stress and absence of threat, it helps maintain a steady, regulated internal environment (homeostasis). Dominant most of the time and is involved in everyday activities like digestion

EG. brings heart rate and respiration rate to a normal level, stimulates salivation and stomach contractions.

Question 9

What is the difference between concious and unconcious responses?

Answer 9

Conscious responses: a reaction to a stimulus that involves awareness and attention. It is voluntary and the goal is directed, and can be learnt and controlled. Eg. feeling that it is cold and deciding to put on a jacket. (SOMATIC)

Unconcious responses: a reaction to stimulus that does not involve awareness and is involuntary and automatic. EG. autonomic NS functions like digestion and regulating heart rate.

Question 10

What is the spinal reflex? How does it work?

Answer 10

An automatic, involuntary, unconscious response to stimuli without any involvement of the brain. Activated by the SOMATIC nervous system.

Sensory neurons communicate the info directly to interneurons in the spinal cord due to the urgency, and the spinal cord reactivates the somatic NS to send motor messages down efferent pathways to control skeletal muscles to respond. Meanwhile, sensory messages would continue to the brain so the pain can be conciously percieved and interpreted.
Enables a faster response to enhance survival.

Question 11

How does communication occur within neurons?

Answer 11

1. Information is received on the receptor sites of the dendrites
2. The message is sent to the soma and this is where the action potential (electrical impulse) is generated
3. The message travels along the axon as an action potential
4. This electrical message then reaches the axon terminals

Question 12

How does communication occur between neurons?

Answer 12

1. The neural impulse (action potential) reaches the axon terminals of the presynaptic neuron
2. This causes chemicals called neurotransmitters (stored in vescicles) to be released from the terminal buttons into the synaptic gap
3. The neurotransmitters are picked up by the receptor sites on the dendrites of the postsynaptic neuron
4. NTs that do not bind to receptor sites are absorbed back into the terminal buttons by the presynaptic neuron in a process known as reuptake OR they are broken down by enzymes

Question 13

What is the role of DENDRITES, AXONS, MYELIN, and AXON TERMINALS in neural communication?

Answer 13

DENDRITE: (projections off a soma that have receptor sites) receives info from other neurons and carries it from the synapse to the soma where it is integrated for transmission along neuron as an electrical impulse (action potential)

AXON: (nerve fibre extending from the soma) carries neural information in the form of an action potential along the neuron to axon terminal to be communicate to other neurons.

MYELIN: (a fatty substance that surrounds and insulates the axon has gaps called nodes of ranvier) It protects axon from potential chemical and physical interference to the action potential and allows for the rapid movement of messages along the axon without being interrupted or distorted. Insulation means it can travel faster.

AXON TERMINALS: (endings of axons) secrete NT’s which will carry the message across the synapse in a chemical form to another neuron.

Question 14

How does communication between neurons occur as a LOCK and KEY process?

Answer 14

Every NT has a unique, molecular shape. When they’re released from the vesicles of a presynaptic neuron they bind to a complementary chemically distinct receptor site on the dendrites of a postsynaptic neuron. They must precisely match in order to bind.
Similar to the process of a lock inserting into a key, whereby the neurotransmitter is the key, and the receptor site is the lock.
This binding then ‘unlocks’ a response in the postsynaptic neuron to cause either an excitatory or inhibitory response

Question 15

What are excitatory effects? What is glutamate? What happens when there is too much or too little glutamate?

Answer 15

Excitatory effects: when a neurotransmitter stimulates or activates a postsynaptic neuron to perform its functions

GLUTAMATE - enhances information transmission by making postsynaptic neurons more likely to fire; plays crucial roles in the growth and strengthening of synaptic connections during learning and memory formation

good level of glutamate = enhanced memory and learning

Too much = can cause anxiety and restless ness or overexcition of neurons which causes neural damage or death.

Too little = insomnia and concentration issues. Weakened memory and learning

Question 16

What are inhibitatory effects? What is GABA? What happens when there is too much or too little GABA?

Answer 16

Inhibitatory effects are when a neurotransmitter blocks or prevents a postsynaptic neuron from firing and therefore performing its functions.

GABA works to counter balance glutamate and fine tune neurotransmission in the brain to maintain it at an optimal level. Reduces neuron excition by inhibiting neurons from firing.

Too much - not enough brain activity causing hypersomnia and drowsiness.

Too little - Without GABA activation of post-synaptic neurons may get out of control, leading to seizures, epilepsy, or mood disorders. Anxiety symptoms like phobias are connected to low levels of gaba.

Question 17

What is parkinsons disease?

Answer 17

a chronic and degenerative neurological condition that affects both motor and non-motor functions; believed to primarily result from the degeneration and loss of dopamine-producing neurons in the substantia nigra in the basal ganglia of the mid brain.

Question 18

What are three motor symptoms, and three non-motor symptoms of parkinsons disease?

Answer 18

MOTOR
1. tremors (continuous, involuntary shaking)
2. bradykinesia (slowness of voluntary movements)
3. muscle rigidity (tight muscles, can’t relax)

NON-MOTOR
1. speech problems like a change in fluency
2. decrease or loss of smell (anomosia)
3. disturbed temperature regulation.

Question 19

What is the role of DOPAMINE in parkinsons disease? Explain the process?

Answer 19

• Neurons in the substantia nigra (structure in midbrain) produce dopamine neurotransmitters so when it is diseased or damaged, the amount of dopamine producing neurons declines.
• Dopamine carries messages that allow smooth coordinated function or movement.
• When there are fewer neurons, less dopamine is produced, meaning structures (eg. primary motor cortex) that are involved in planning, coordinating, and initiating voluntary movements receive slower, fewer and/or irregular dopamine messages about motor activity.
• subsequently, motor activity is impaired, causing symptoms of parkinsons disease

Question 20

What is the role of GABA in parkinsons disease?

Answer 20

Neurons in the midbrain that release dopamine also release GABA, which inhibits or lowers normal neuron activity.

Depleted levels of GABA can lead to the onset of mental health problems such as anxiety, this is because GABA has a calming effect and prevents neurons from being over-excited.
Also believed to possibly contribute to symptoms like restless leg syndrome and tremors due to an overexcition of neurons.

Question 21

What is the difference between eustress and distress?

Answer 21

Eustress: positive psychological responses to a stressor, indicated by the presence of positive psychological states eg. feeling excited, motivated, and alert. Typically short term and provides the energy and motivation necessary to reach a goal. NOT HARMFUL.

Distress: negative response to a stressor. Indicated by the presence of negative psychological states eg. anger, anxiety, nervousness. HARMFUL.

All stressors produce a non-specific stress response. Eg both good news and bad news can increase your heart rate, and breathing rate. Whether an event is eustressful or distressful depends on an individual’s personality, prior experience, and perception of it.

Question 22

What are the five different types/sources of stress?

Answer 22

Daily pressures: involves a small everyday living problem. Eg. argument with a friend. Can accumulate and create physical problems eg. a cold and become a major stress source.

Life events: a change that forces you to adapt to new circumstances eg. new job, break up

Acculturative stress: the stress people experience in trying to adapt to a new culture when living in it for a considerable period of time. Eg. when refugees/immigrants must adapt to the customs and values of a new country.

Major stress: an event that is extraordinarily stressful or disturbing for most people who experience it. Involves psychological trauma. Eg. rape, murder, abuse, natural disasters.

Catastrophes: events that cause widespread damage or suffering and disrupt an entire community. Eg. terrorist attack, bushfires.

Question 23

What are physical, cognitive, emotional, and behavioural symptoms of psychological trauma?

Answer 23

Physical: hypervigilance (i.e. excessive alertness, on the lookout for signs of danger); easily startled; fatigue/exhaustion; disturbed sleep; general aches and pains

Cognitive: intrusive thoughts and recurring memories of the event; visual images of the event; nightmares; poor concentration and memory; disorientation; confusion

Behavioural: avoidance of places or activities that are reminders of the event; social withdrawal and isolation; loss of interest in normal activities

Emotional: fear; numbness and detachment; depression; guilt; anger and irritability; anxiety and panic.

Question 24

What are the different levels of stress?

Answer 24

Episodic acute stress: Acute stress that occurs over and over again. These kinds of repetitive short-term stress episodes may be due to a series of life challenges

Acute stress: Stress we experience can sometimes be brief and specific to the demands of a particular situation. Tends to produce a very high arousal level for a relatively short time

Chronic stress: Ongoing demands, pressures & worries that are long-lasting. Can seem to go on forever, with little hope of letting up. Produces an increased arousal level that persists over a relatively long time & is likely to be harmful in some way to health and wellbeing, both psychologically and physically

Question 25

What is the fight-flight response?

Answer 25

In reacting to a stressor we will either flight from it, or fight. What occurs depends on what is likely to enhance survival.

In order to prepare the body for either fight or flight, all energy is directed from non-essential body systems to those that will help you survive. Initiated by the SYMPATHETIC NERVOUS SYSTEM

EG. Increased heart rate, redistribution of blood supply from skin and intestines to skeletal muscles, increased breathing rate.

Question 26

What is the freeze response?

Answer 26

When we cannot run away and are unable to fight, we go into a state of tonic immobility (ie. freeze state). Body movements and vocalisations stop, Racing heart slows very significantly, blood pressure drops very quickly, Tense muscles collapse and become still.

When it starts, the parasympathetic nervous system is dominant over the sympathetic, but both are heightened. Therefore, the body is in a state of high arousal so energy is conserved but the body is in a mobilised state ready for action

Question 27

What is the role of cortisol in stress responses?

Answer 27

When we must deal with a stressor for a long time, we cannot maintain intensity of the FFF response, so the HPA axis is initiated to release cortisol.

When cortisol is released into blood stream, it energises body by increasing blood sugar levels (eg. stimulates liver to secrete glucose to be used by muscles). Also has an antinflmmatory effect by supressing white blood cells (ie. supresses immune system so FFF can continue).

However, it also has negative effects when cortisol levels remain in blood stream at a high level fro a long time as it supresses the immune system so the body becomes more suceptible to illnesses like colds. And because it stimulates glucose secretion it can cause hyperglycemia

eg. physical problems like colds, flus, hypertension, hyperglycemia
eg. psychological problems like impaired memory, anxiety, and depression

Question 28

What is stage one of the GAS?

Answer 28

ALARM REACTION
SHOCK - the body goes into a state of shock and the ability to deal with a stressor falls beyond normal level. Physiologically, the body acts injured (eg. blood pressure and body temperature drop)
COUNTERSHOCK - body rebounds from shock. The sympathetic nervous system becomes activated and the body’s ability to resist the stressor increases, meaning there is a higher level of alertness and arousal as the body prepares to deal with a stressor. Adrenaline is released into the bloodstream and the organism’s heart and respiratory system respond by accelerating. This supplies the muscles with more energy (glucose and oxygen), allowing the organism to ‘fight or flee’, as needed.

Question 29

What is stage two of the GAS?

Answer 29

RESISTANCE
If the stressor is not dealt with immediately, energy is still needed and the body must keep responding. Physiological arousal stays above normal level and all unnecessary processes such as digestion and growth, are shut down.
Corticosteroids such as cortisol are released into the bloodstream to further energise the body and provide pain relief. However, because cortisol can weaken immune system activity, it’s continuing presence can make the body more susceptible to illnesses eg. colds. This causes things like colds, however not too serious.

Question 30

What is stage three of the GAS?

Answer 30

EXHAUSTION:
The body can no longer sustain its resistance as it’s resources have been depleted. The organism is very weak and more vulnerable to physical and mental disorders. Brings about signs of wear and tear due to the immune supression.
More serious issues that don’t go away on their own and need a doctor. Eg. physical disorders like heart disease, hypertension, gastrointestinal problems

Question 31

What are two strengths of Selyes GAS?

Answer 31

1. Shows how stress can weaken the body’s capacity to resist infections and make the body more susceptible to illness and physical and mental disorders. EG. shows strong links between stress and cardiac and kidney diseases.
2. Outlines how biological processes, such as the role of the endocrine system, are involved in how the body responds to stress.

Question 32

What are two weaknesses of Selyes GAS?

Answer 32

1. Assumes that everyone has the same predictable responses to stressors and does not account for variations in responses.
2. Primarily based on the results of animals and may not be as relevant and applicable to humans.

Question 33

What is Lazurus and Folkmans transactional model of stress and coping?

Answer 33

proposes that stress involves an encounter between an individual and their environment, and that a stress response depends upon both the appraisal of the stressor and the ability to cope with it.

Believes that an individual’s appraisal of a situation and their resources for dealing with it, determine whether or not they experience stress and the nature of their stress response.

This subjective appraisal is influenced by the person’s beliefs, goals, personal circumstances, life experiences and personality.

Question 34

What is primary appraisal? (L&F model of stress and coping)

Answer 34

first we evaluate whether something is IRRELEVANT, BENIGN-POSITIVE or STRESSFUL

If it’s stressful, it’s either because HARM has been caused, there is a possible THREAT, or there is a CHALLENGE that may have an opportunity for a positive outcome. If we evaluate it to be stressful, we will engage in a secondary appraisal.

Question 35

What is secondary appraisal? (L&F model of stress and coping)

Answer 35

We evaluate our ability to control or overcome a situation. This includes an evaluation of our coping options and resources for dealing with the event. eg. prior experience, money, support

ADEQUATE RESOURCES to deal with it = no stress response

INADEQUATE RESOURCES to deal with it = stress response

Question 36

What are two strengths of L&F transactional model?

Answer 36

1. Emphasises the personal nature and individuality of the stress response.
2. Explains why individuals respond in different ways to the same types of stressors

Question 37

What are two weaknesses of L&F transactional model?

Answer 37

1. Doesn’t account for how we can experience a stress response without ever having thought about a situation or event (i.e. appraisal is not essential)
2. Difficult to test through experimental research because of the subjective nature of individual responses to stressors

Question 38

what is context-specific effectiveness?

Answer 38

in relation to coping with stress, when there is a match or ‘good fit’ between the coping strategy that is used and the stressful situation.

In order for a coping strategy to be effective it must consider:
1. the nature of the stressor (e.g. chronic) and does it actually address the stressor
2. the individual (e.g. appraisal, personality, support, past experience)
3. circumstances or context of the situation

Question 39

What is coping flexibility?

Answer 39

Coping flexibility refers to one’s ability to effectively modify or adjust their coping strategy according to the situation eg. Recognising if the strategy is appropriate, selecting the best strategy, and recognising if a strategy is ineffective and discontinuing it.

People with high coping flexibility:
1. adjust their strategies to fit a specific situation
2. have high context-specific effectiveness
3. recognise when a strategy isnt working

People with low coping flexibility:
1. Use the same type of strategy across different situations
2. Continue to persist with an ineffective strategy.
3. Context-specific effectiveness tends to be lower

Question 40

What are approach strategies? Positives and negatives?

Answer 40

Involves an effort to cope with stress by confronting the causal stressor and dealing directly with it and its effects

POSITIVES
- allows individual to feel more in control
- is generally more adaptive and healthy as it involves a change in behaviour to directly deal with a stressor

NEGATIVES
- may initially increase stress levels while engaging with the stressor
- may require alot of energy and cause individual to neglect other aspects of their life

Question 41

What are avoidance strategies? Positives and negatives?

Answer 41

involve an effort to cope with stress by evading the causal stressor and indirectly dealing with the stressor and its effects

POSITIVES
- If someone is experiencing a number of stressors, then avoidance may be a necessary technique so you can focus on stressors that you have the potential to change.
- Allows us to deal with the intense emotions that have been triggered by an especially overwhelming stressor.

NEGATIVES
- Maladaptive approach as it does not help people to develop effective strategies
- If they are used for too long they prevent people responding to stressors constructively.

Question 42

What is exercise in terms of stress? How does it help deal with a stressor?

Answer 42

Physical activity that is usually planned and performed to improve or maintain one’s physical condition and can be useful in stress management.
Being physically active, especially exercise that requires a sustained increase in oxygen consumption, can significantly reduce the risk of a serious disease, including those associated with chronic stress

This is because:
1. Using up stress hormones in the bloodstream means the body can return to a homeostatic state sooner.
2. Can work out muscle tension that has built up during a stress response.
3. Offers a distraction from the stressor
4. Release mood enhancing beta-endorphins.

Question 43

what is the fight/flight/freeze response?

Answer 43

An involuntary, physical response to a sudden and immediate threat (or stressor) in readiness for fight (confront), flight (escape) or freeze (be still and silent). Triggered by the autonomic nervous system. Sympathetic for fight/flight, parasympathetic for freeze (though sympathetic is still activated)