UNIT 3 AOS1 - SAC 1

Question 1

Explain the Human Nervous System.

Answer 1

= A complex highly organised network of specialised cells that enables the brain to receive information from both inside and outside the body, and to respond appropriately.

Its three main functions are to:
* receive information
* process information, and
* coordinate a response to information.

Question 2

Outline the major divisions and sub-divisions of the human nervous system (diagram).

Answer 2

Question 3

Explain the central nervous system (CNS).

Answer 3

= The combination of the brain and the spinal cord.

• Function: to process information received from the body’s internal and external environments and to activate as appropriate.

Question 4

Explain the brain.

Answer 4

• A subdivision of the CNS

= An intricate network of cells - vital in processing information received through neural pathways from the body and in directing actions within the body.

• It continuously receives and analyses sensory information, responding by controlling all bodily actions and functions.

Question 5

Explain the spinal cord.

Answer 5

• A subdivision of the CNS

Two major functions:
RECEIVE sensory information from the body and send it to the brain for processing.
RECEIVE motor (movement) information from the brain and send it to relevant parts of the body.

Question 6

Explain the peripheral nervous system (PNS).

Answer 6

= The entire network of nerves located outside the CNS.

• Carries information to the CNS from the body’s muscles, organs and glands (about the internal environment) and from the sensory organs (about the external environment)
• Carries information from the CNS to the body’s muscles, organs and glands.

Question 7

Brain processes and information transmission are involved in picking up a water bottle (image).

Answer 7

Question 8

Explain the somatic nervous system.

Answer 8

• A subdivision of the PNS

= Receives sensory information from our skin, muscles, and joints and it sends motor information for movement to our skeletal muscles. (Voluntary)

• Involved in all skeletal muscle activity that enables us to participate in our relationship with the external environment.

Question 9

Explain the autonomic nervous system.

Answer 9

• A subdivision of the PNS

= Connects the CNS to the body’s internal organs (eg. heart) and glands (eg. sweat), providing feedback to the brain about their activities. (involuntary - AUTONOMOUS)

• Self-regulating and therefore occur without conscious effort

Question 10

Explain the sympathetic nervous system.

Answer 10

• A subdivision of the autonomic NS

= Activates internal muscles, organs and glands to prepare the body for vigorous activity or to deal with a stressful or threatening situation.

It is activated by a stressor and enhances survival by providing an immediate response.

Question 11

Explain the parasympathetic nervous system.

Answer 11

• A subdivision of the autonomic NS

= Helps to maintain the internal body environment in a steady, balanced state of normal functioning (even in the absence of threat/stress).

Restores the body to a state of calm, once the need for sympathetic nervous system activation has passed.

Counterbalances the activities of the sympathetic nervous system.

Question 12

List the activities of the sympathetic and parasympathetic nervous systems.

Answer 12

Question 13

Explain the enteric nervous system.

Answer 13

Is embedded in the walls of the gastrointestinal tract and is dedicated to its functioning.

• It is a mesh-like system of clusters of neurons (called ganglia) that exist all the way from the esophagus to the rectum.

Enteric Nervous System Roles
* Detects gastrointestinal tract physiological condition.
* Controls muscle contractions and nutrient management.
* Works with CNS for digestion control.
* Can function independently of brain/CNS.
* Regulates response to food/drink intake.

Question 14

Define a conscious response.

Answer 14

A response to a sensory stimulus that involves AWARENESS. You will have paid attention to the stimulus and voluntarily, intentionally reacted to it.

Question 15

Define unconscious response

Answer 15

A response to a sensory stimulus that does NOT involve awareness. It is involuntary, unintentional, automatic and we cannot control it. Responses by our Autonomic NS are unconscious for example.

Question 16

Define the spinal reflex (reflex arc)

Answer 16

An unconscious, involuntary and automatically occurring response to stimuli initiated within the spinal cord without any involvement from the brain.

A survival mechanism.

Question 17

Explain the spinal reflex (reflex arc) process.

Answer 17

STEPS to remember:

1. Sensory receptors on the skin receive sensation and send it along sensory neural pathways to the spinal cord.
2. Interneurons in the spinal cord receive and initiate a response as a survival mechanism.
3. This message is sent along motor pathways to the point of need (to withdraw hand etc,.)
4. The message completes its journey to the brain which then registers pain and can initiate further action if required.

NOTE: Neurons have been removed from this study design specifically but you should still know them from previous years. You will not need to name their components etc, but will need to name them within processes such as this.

**Exam tip - this is generally a 4 mark question - these are the four main bits of info you need to present, in ORDER!

Question 18

Steps to remember (image).

Answer 18

Question 19

An example of an unconscious reaction is the ‘Reflex Arc’ (chart).

Answer 19

Question 20

Neurons.

Answer 20

SAME - Neurons

Sensory
Afferent

Motor
Efferent

**EXAM TIP: You can use either word (Sensory/Afferent or Motor/Efferent - but the question may refer to either so you need to know both!

Question 21

Neurons reminder (diagram).

Answer 21

Question 22

Explain sensory/afferent and motor/efferent neural pathways.

Answer 22

SENSORY/AFFERENT
A neural pathway that carries information towards the brain or spinal cord (e.g. sensory information.

MOTOR/EFFERENT
A neural pathway that carries information away from the brain or spinal cord (e.g. motor information)

Question 23

Explain neurotransmitters.

Answer 23

A chemical substance produced by a neuron that carries a message to other neurons or cells in muscles, organs or other tissue.

• Works by binding to receptor sites of post-synaptic neurons, which are specialized for that type of neurotransmitter.
• Any neurotransmitter that doesn’t bind to the receptors is reabsorbed by the pre-synaptic neuron, a process called reuptake.
• When neurons communicate with one another, they do so by sending neurotransmitters across the tiny space between the terminal buttons of one neuron.
• The tiny space between neurons is called the SYNAPTIC GAP.
• The SYNAPSE is the site where communication occurs between adjacent neurons.
• The other two components of the synapse are the terminal buttons of the PRE-SYNAPTIC NEURON and the dendrites of the POST-SYNAPTIC NEURON.

The car on the highway (neurons)

Question 24

Explain the two effects of neurotransmitters.

Answer 24

EXCITATORY – stimulate and activate postsynaptic neurons to perform their functions.

INHIBITORY – block or prevent postsynaptic neurons from firing.

Question 25

Explain glutamate

Answer 25

Your mate/friend

The primary EXCITATORY neurotransmitter.
This means that it ENHANCES information transmission by making postsynaptic neurons more likely to fire.

• Involved in perception, learning, memory, thinking and movement.

Question 26

Explain gaba.

Answer 26

Your mum

The primary INHIBITORY neurotransmitter in the CNS.

It works by making POSTSYNAPTIC neurons LESS likely to fire. It FINE TUNES the neurotransmission of the brain and maintains an optimal or ‘best possible’ level.

• Without GABA, the activation of Glutamate might get out of control, causing seizures etc.
• Anxiety symptoms have also been linked to low levels of GABA.
• GABA counterbalances Glutamate and vice versa.

Question 27

Explain neuromodulators.

Answer 27

A type of neurotransmitter that can influence the effects of other neurotransmitters; also called modulator neurotransmitter.

For example, if a neurotransmitter has modulatory effects, it can change the reactivity of receptors to another type of neurotransmitter to enhance their excitatory or inhibitory responses.

• Works with other Neurotransmitters to enhance effect
• Release chemicals into numerous synapses
• Slower to impact that neurotransmitters
• Main two are Dopamine and Seratonin

Question 28

Identify and briefly explain the two types of neuromodulators.

Answer 28

• Dopamine and serotonin modulate neural activity in the CNS.
• Their effects on brain activity, mental processes, and behavior vary.
• Too much or too little dopamine or serotonin can have detrimental effects.
• Dopamine and serotonin interact, counterbalancing each other’s effects.

Question 29

Explain dopamine.

Answer 29

Neuromodulator with multiple functions depending on where it acts; functions include important roles in voluntary movements, the experience of pleasure, motivation, appetite, reward-based learning and memory.

• Linked to Parkinson’s disease, addiction and schizophrenia.
• Primarily excitatory neurotransmitter, can have excitatory or inhibitory effects depending on receptor type.

Dopamine-releasing behaviours can be both healthy (eating when hungry) and harmful (gambling), affecting impulse control and addiction.

Question 30

Identify and explain the three main pathways which Dopamine is involved in in the brain.

Answer 30

NIGROSTRIATAL, MESOLIMBIC and MESOCORTICAL.

• The pathway stemming from the SUBSTANTIA NIGRA (nigrostriatal) is involved in coordinating smooth and coordinated movement.
• The other main Dopamine pathways (mesolimbic and mesocortical) overlap and are strongly associated with the experience of pleasure and its role in rewarding behaviour.

Question 31

Explain serotonin.

Answer 31

Neuromodulator with multiple functions depending on where it acts; functions include: mood, emotional processing, sleep onset, appetite and pain perception.

• Has been implicated in various mental conditions, including depression, anxiety disorders and sleep disorders.
• Only has inhibitory effects, so it does not stimulate brain activity.
• Mood stabaliser
• The right amount of serotonin is required for us to feel positive, calm and have a stable mood.

Question 32

Explain learning.

Answer 32

The acquisition of new information, behaviour or abilities that occurs as a result of experience. For learning to have occurred, it must be RETAINED in memory.

The existence of memory indicates that learning has occurred. If no learning occurs there is nothing to remember.

• DO LEARN: beliefs, opinions, interests, attitudes, etc.
• DONT LEARN: breathing, blinking etc.
• It is an ongoing process that continues throughout our lifespan enabling us to adapt and cope in the ever-changing world.

Question 33

Explain the neural basis of learning.

Answer 33

The Basic structure of the Nervous System is set before birth (Brain, hemispheres, lobes etc.)

Neurons however, are flexible living cells that can grow new connections and change in size, shape and even function.

Question 34

Define synaptic plasticity (also known as neural plasticity).

Answer 34

The ability of the brain’s neural structure or function to be changed at the synapse due to experience.

This allows for both strengthening and weakening of the connections between neurons.

Question 35

Explain the Hebbian Theory.

Answer 35

• Learning involves the creation and strengthening of neural connections at the synapse.
• EG: Learning the piano will CREATE/ESTABLISH new neural connections and regular piano practice will STRENGTHEN the neural connections.
• Hebb proposed that learning results in the creation of cell assemblies or neural networks.
• ‘neurons that fire together wire together’

Question 36

Define sprouting.

Answer 36

The creation of new extensions on a neuron to allow it to make new connections with other neurons

Question 37

Define rerouting.

Answer 37

When new connections are made between neurons to create alternate neural pathways

Question 38

Define pruning.

Answer 38

The elimination of weak, ineffective or unused synapses (and therefore connections to other neurons);

Question 39

Explain Long-term potentiation (LTP).

Answer 39

Long lasting strengthening of the synaptic connections of neurons, resulting in the enhanced or more effective functioning of the neurons whenever they are activated.

• LTP is CRUCIAL to learning
• LTP leads to increased release of neurotransmitters as well as the growth of new dendritic spines - bushier dendrites. LTD reduces these.

Question 40

Explain Long-term Depression (LTD).

Answer 40

Is the opposite of LTP. A long-lasting decrease in the strength of synaptic transmission.

• This occurs from a lack of or low level stimulation of pre and postsynaptic neurons.
• “Use it or lose it” approach.
• Just as important as LTP in pruning unused or unwanted connections leaves only those deemed important or necessary.
• Allows us to correct our thinking or adjust an incorrect behaviour.
• EG. Correct an error when serving in tennis.

Question 41

List the similarities between LTP and LTD.

Answer 41

• Both are activity dependent; that is, more or less activity
• Both involve glutamate
• Both occur at glutamate synapses
• Both involve changes in excitability
• Both have long-lasting effects
• Both are forms of long-lasting neural plasticity.

Question 42

Explain stress and list the two types of stress and the two responses of stress.

Answer 42

A psychological and/or physiological response produced by internal or external stressors.
- Begins in the brain
- Acute and Chronic Stress

Physiological responses are involuntary and predictable (sweating, heart pounding etc).

Psychological responses are not involuntary and we can have a degree of control over them.

Question 43

Define a stressor and list the two types.

Answer 43

Any stimulus (person, situation or event) that produces stress. It can be internal or external.

• Virtually anything can be a stressor and therefore a cause of stress to an individual.
• Internal + External stressors

Question 44

Explain an internal stressor.

Answer 44

Originates within the individual.

Eg. A personal problem which you are worried about the outcome of (worry about achieving a high ATAR)

Question 45

Explain an external stressor.

Answer 45

Originates outside the individual from situations and events in the environment.

Eg. Too much homework, being in an overcrowded train, arguing with a friend.

Question 46

Explain acute stress.

Answer 46

Stress that lasts for a relatively short time. The body usually bounces back quite quickly if the stress is managed by the person.

EG. Running late for an appointment, waiting for an exam to start, doing an oral presentation.

• Can cause elevated blood pressure and reduced motivation
• Can be beneficial by releasing Adrenaline, aiding in task completion and problem-solving

Question 47

Explain chronic stress.

Answer 47

Stress that continues for a prolonged period of time. Involves ongoing demands, pressures and worries that are constant and long lasting.

EG. Ongoing financial difficulties, social isolation/loneliness, relationship problems, long lasting health problems, bullying.

Question 48

Explain the Fight-Flight-Freeze Response.

Answer 48

Acute stress response.

An involuntary, bodily response to a sudden and immediate threat (or stressor) in readiness for fight (confront), flight (escape) or freeze (be silent and unseen).

Question 49

Explain the freeze response.

Answer 49

FREEZE - a different process to Fight and Flight (Also known as Tonic Immobility)

• In the freeze state, movements stop, racing heart slows, blood pressure drops, muscles can collapse and become still.
• An organism is on guard, alert, but still.
• Allows them to avoid detection and conserve energy.
• Biological processes involved are not fully understood. The parasympathetic NS is dominant instead of the sympathetic NS.

Question 50

Explain the Role of Cortisol in Chronic Stress.

Answer 50

PRIMARY STRESS HORMONE

• Involved in both acute and chronic stress
• Acts slowly and lasts longer than other stress hormones.
• Quick rise in cortisol levels followed by a rapid decline.
• Prolonged activation/long term cortisol elevation can be harmful to our immune system.
• Can also impact cognitive functioning

Question 51

Explain the Gut-Brain Axis.

Answer 51

A bidirectional (two way), multifaceted communication link between the central and enteric nervous systems.

It involves pathways between cognitive and emotional areas of the brain and the gastrointestinal tract.

EG. When we feel stressed or anxious, we may end up with an upset stomach.

• Can influence the production of serotonin and other neurotransmitters
• Enter the blood stream and communicate with organs
• Influence a range of other bodily systems

Question 52

Explain the Gut Microbiota.

Answer 52

All the organisms (eg. bacteria, viruses, fungi) present in one’s digestive tract.

We call a large number of microbiota in a defined environment a MICROBIOME.

Question 53

List how the gut microbiota is linked to stress.

Answer 53

• Stress can disturb the balance of gut microbiota and the microbiota can influence a person’s experience of stress.
• Manipulation of gut microbiota (using probiotics/good bacteria) can promote healthy gut brain microbiota interactions, thereby reducing stress.
• The brain and gut communicate constantly this communication can be impacted by stress.

Question 54

Explain the vagus nerve.

Answer 54

The vagus nerve is thought to be largely responsible for the bidirectional mind-body communication (gut-brain axis).

• Crucial role in thoughts, feelings, and behaviours.
• Stimulation may trigger relaxation response, reducing heart rate and blood pressure.

Question 55

Briefly explain Hans Selye’s studies that led to GAS.

Answer 55

Physiological (Bodily) Responses to Stress

• Most of Selye’s stress studies used rats who were exposed to a variety of stressors. (eg. Tail pulling, electric shocks etc).
• Regardless of the stressor, the results were relatively similar – enlarged adrenal glands, weight loss, stomach ulcers and depleted immune system etc.
• He then concluded that stress is non-specific and can be brought on by internal or external stressors.
• Humans react in much the same way to stress.

Question 56

List the stages of GAS.

Answer 56

1. Alarm reaction
2. Resistance
3. Exhaustion

Question 57

Explain the stage of alarm reaction.

Answer 57

• Occurs when the person/animal is first exposed to the stressor.
• Body goes into temporary state of ‘shock’ – body temp and blood pressure drop. RESISTANCE TO STRESS dips below normal.
• The body then quickly rebounds from this during what is called ‘countershock’. RESISTANCE TO STRESS increases to above normal.
• Sympathetic NS is activated and a reaction like that of the fight-flight response occurs.

The body cannot stay in this state for long without serious consequences. Some organisms in a continuous state of alarm have died within hours or days

Question 58

Explain the stage of resistance.

Answer 58

• If the reaction continues and is not strong enough to cause death the physiological reaction enters the stage of resistance.
• The body tries to adapt to the stressor. Physiological arousal declines but remains higher than normal and the body replenishes the hormones released by the adrenal glands.
• Resistance to stress is ABOVE NORMAL LEVEL
• Increasingly vulnerable to health problems.

Question 59

Explain the stage of exhaustion.

Answer 59

• Severe long-term or repeated stress will cause the organism to enter the third stage, the stage of exhaustion.
• The immune system and the body’s energy reserves are weakened until RESISTANCE TO STRESS is very limited/below normal level.
• If the stress continues, disease and physiological damage become increasingly likely and death may result.

Question 60

List the strengths and limitations of General Adaptation Syndrome (GAS).

Answer 60

STRENGTHS
- Influential understanding of the endocrine system
- Influential understanding of links between stress and disease.

LIMITATIONS
- Assumes everyone is the same and will respond the same way.
- Understates the roles of other body systems other than endocrine system.
- Overlooks our psychological responses.

Question 61

Define Lazarus and Folkman’s Transactional Model of Stress and Coping.

Answer 61

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

• Psychological model

Question 62

Explain primary appraisal.

Answer 62

1) Primary appraisal = the recognition of a potentially stressful situation.

• The person evaluates/judges the significance of the situation
• Assesses it as stressful, benign-positive or irrelevant.

If assessed as stressful, then we engage in additional appraisals:
- Harm/loss – how much damage has already occurred?
- Threat – what harm/loss could occur in the future?
- Challenge – what potential for personal gain or growth is there from the situation?

Question 63

Explain secondary appraisal.

Answer 63

2) Secondary appraisal = considering what options are available and how best to respond to the situation.

• Evaluate our coping options and resources
• Internal resources – strength, determination
• External resources – money, support from family

If the coping demands are perceived as being greater than the resources available we are more likely to experience a stress response.

Question 64

List the strengths of Lazarus and Folkman’s Transactional Model of Stress and Coping.

Answer 64

• Bridged biological and cognitive explanations of stress.
• Explained interaction between individual and environment, focusing on perception.
• Used human subjects for model development.
• Focused on psychological determinants of stress response, not involuntary physiological responses.
• Employed cognitive approach to stress, focusing on psychological stressor coping.

Question 65

List the limitations of Lazarus and Folkman’s Transactional Model of Stress and Coping.

Answer 65

• Difficult to test through experimental research due to subjective, variable, and complex responses.
• Difficult to isolate primary and secondary appraisals due to interaction.
• Individuals may not always recognize all stress-causing factors.
• Focus on psychological factors over physiological elements.
• Doesn’t consider cultural, social, or environmental factors in stress perception.

Question 66

Define coping.

Answer 66

The process of constantly changing cognitive and behavioural efforts to manage specific internal and/or external stressors that are appraised as exceeding the resources of the person.

Question 67

Define a coping strategy.

Answer 67

A specific method, behavioural or psychological, that people use to manage or reduce the stress produced by a stressor.

Question 68

Define context-specific effectiveness.

Answer 68

A coping strategy is considered to have context-specific effectiveness when there is a match or ‘good fit’ between the coping strategy that is used and the stressful situation.

Question 69

Define coping flexibility.

Answer 69

Psychologists use the term coping flexibility to refer to the ability to effectively modify or adjust one’s coping strategies according to the demands of different stressful situations.

Question 70

Define approach focused coping strategies

Answer 70

Involve efforts to confront a stressor and deal directly with it and its effects.

Question 71

Define avoidance coping strategies

Answer 71

Involve efforts which evade or avoid the stressor and deal indirectly with it and its effects. Activity focussed elsewhere and no attempt to confront the issue.

Eg. Going for a walk and playing video games instead of studying for a SAC.

Question 72

List the fight or flight response.

Answer 72

Question 73

Outline the General Adaptation Syndrome (GAS) (diagram).

Answer 73

*You must be able to accurately describe where the blue line falls within this graph, with reference to ‘resistance to stress.’

Question 74

Outline Lazarus and Folkman’s Transactional Model of Stress and Coping (diagram).

Answer 74