Psychology Exam Revision PDF

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Psychology unit 3 and unit 4 summarised to assist with exam revision ...

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Unit 3 AOS1

" The Central Nervous System" * CNS comprises of the brain and the spinal cord" Spinal Cord" * Runs from the base of the brain, inside the bones of the spine to the lower middle section of the spine" * Enables the brain to communicate with the rest of the body by conveying messages from the brain to the PNS and vice versa" Brain" * An intricate network of cells that plays a vital role in processing information received through neural pathways from the body and in directing actions within the body" Control Centre" * Crucial role in everything we think, feel and do" The Peripheral Nervous System" * The PNS has two functions" 1. To communicate information from the body’s organs, glands and muscles to the CNS from both the outside world and the inside world" 2. To communicate information from the CNS to the body’s organs, glands and muscles via motor neurons" Two subdivisions of the PNS" * Somatic nervous system" * Autonomic nervous system" The Somatic Nervous System" * Responsible for the voluntary movement of skeletal muscles" * Motor neurons (nerves) communicate messages from the CNS to the particular muscles that an organism intends to move at any moment" * The CNS and PNS work together to enable an organism to interact with the environment" * Sensory neurons (nerves) convey any sensations detected by sensory receptors" The Autonomic Nervous System" * Mostly responsible for the communication of information between the CNS and the body’s non skeletal muscles (smooth/visceral muscles) and internal organs and glands that carry out the basic bodily functions necessary for survival (heart beat)" * Operates without voluntary control or conscious awareness and enables the organism to have the cognitive resources to pay attention to other matters such as responding to threats"

The Sympathetic Nervous System" * Typically activated in response to threats and its job is to prepare the body for fight, flight or freeze" * Stops digestion by diverting blood away from the stomach and redirecting it to the muscles" * Increases heart rate, dilates pupils and causes hairs on body and head to erect" * By preparing our body to respond in emergencies, this system serves an important adaptive function" The Parasympathetic Nervous System" * Supports more routine activities that maintain the body’s store of energy such as regulating blood-sugar levels, secreting saliva, eliminating waste and regulating heart rate and pupil size" * The relationship between the sympathetic and parasympathetic nervous systems is in many ways a balancing act" Responses" * Responses to internal and external stimuli can be conscious (talking) or unconscious (breathing) " * We distinguish between these responses by looking at whether or not there is awareness" Conscious response to stimuli" * Reaction involves awareness" * Paid attention to stimulus" Unconscious response to stimuli" * Reaction doesn’t involve awareness" * Don’t have to pay attention for it to happen" Spinal Reflex (reflex arc)" * An unconscious, involuntary and automatically occurring response to certain stimuli without any involvement of the brain" * This response is unlearned and innate" * Response at the spinal cord enables faster reaction time " * Adaptive response saves time in a situation that may be harmful - increasing chances of survival" * Absence of this response could indicate damage within the sensory/motor pathways or a spinal cord injury" Detailed example * If you touch the hot handle of a frying pan you would automatically withdraw your hand to release the handle before the sensory information travels all the way to your brain and pain is actually experienced. The sensory receptors in your finger would send messages to your CNS, but the first point of contact in the CNS is the spinal cord. Here interneurons transfer the message between sensory neurons and motor neurons. It responds with a message via motor neurons to move the appropriate muscles in your hand to release the hot object and withdraw the hand" Interneurons" * Only found in CS" * Can communicate between sensory and motor neurons"

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The Role of Neurons" * Neurons receive information from other neurons, process this information and then communicate it to other neurons" * Neurons receive, process and transmit information to each other" * They comprise of 3 elements - dendrites, soma and axon" Neurons" * There are 3 types of neurons that make up the nervous system" 1. Sensory (afferent) neurons * Transmit impulses to CNS from receptors" * Impulses arrive at the brain" 2. Interneurons (connector neurons) * Connect motor and sensory neurons" * Impulses travel through CNS" 3. Motor (efferent) neurons * Transmit impulses from CNS to muscles" * Impulses exit the brain" The Role of Dendrites" * Receive information from other neurons or sensory receptors via synapses and deliver this to the cell body or soma" * Synapses are tiny gaps across which a nerve cell or neutron can send an impulse to another neuron"

# # The Role of the Soma (cell body)" * The largest part of the neutron" * Controls the metabolism and maintenance of the cell" * Information is integrated in the soma" The Role of the Axon" * Nerve fibre that carries information away from the soma to their ends toward other cells that communicate with the neuron" * This information is referred to as action potential - consists of brief changes in the electrical charge of the axon" * The end of each axon has terminal buttons that secrete a chemical called a neurotransmitter whenever information is sent down the axon in the form of electrical impulses" The Role of Myelin" * A white fatty substance that surrounds and insulates the axon" * Allows for rapid movement of the message along the axon without being interrupted or distorted " * Separated by small unmyelinated gaps: nodes of ranvier" The Role of Axon Terminals" * Contains the terminal button: small sac containing neurotransmitters" * Transmit message to the next neuron through the secretion of neurotransmitters" Neural Communication"

* Electrochemical# Electrical = action potential# Chemical = neurotransmitter" * Communication of messages through neurons" * Adapt to suit frequency and speed" Neurotransmitters" * Specialised" * Different chemicals" * Can alter the electrical activity (interior charge) in other neurons" Lock and Key Process" * Neurotransmitter molecules fit into specific receptor sites" * This is the same way that a key perfectly fits into a lock" * This can either have an excitatory or inhibitory effect" Excitatory" * Stimulates action potential that’s passed as an electrical impulse" Inhibitory # * Prevents action potential from firing# # Inhibitory Neurotransmitters" * ‘Off switches’# Slow down and decrease likelihood of firing" * Induce sleep, calmness (natural tranquillisers)" * Decrease aggression" GABA (gamma-aminobutyric-acid)" * Regulates anxiety" * Reduces stress - calming effect on brain" * Improves mental focus" * Excess = sedation, impaired STM" * Deficiency = anxiety, stress, insomnia, Parkinson’s" Excitatory Neurotransmitters" * ‘On switches’# Speed up and increase likelihood of firing" * Promote alertness, energy and activity" Glutamate" * Long-term potentiation# Creating links between neurons (learning and memory)" * Excess = anxiety, ADHD and seizures" * Deficiency = impaired learning and memory" Dopamine" * Drive, motivation and motor movement" Neurotransmitter Interruption" * Can occur due to imbalance and deficiency " * Can also be naturally occurring or self induced due to alcohol, diet, stress and genetics" Parkinson’s Disease" * Progressively degenerative neurological disorder" * Affects the control of body movements" * When neurons in substantial nigra become impaired or die. This is usually the result of damage or disease to the substantial nigra which controls voluntary muscle movements " Dopamine" * When approximately 70-80% of dopamine-producing cells are damaged, motor symptoms appear. This is because the amount of dopamine for motor activity reduces" * Risk factors are age and genetics (15%)"

Motor Symptoms

Non-Motor Symptoms

Tremor

Decrease/loss of smell

Muscle rigidity

Fatigue

Slowness of voluntary movement (bradykinesia)

Mental health problems

Postural instability, balance problems and walking disturbances

Cognitive function problems (impaired planning, decision making and memory loss (40-50%)

Parkinson’s Disease - Dopamine" * Deficiency causes abnormal nerve-firing patterns and impaired movement # Tremors, rigidity, stiffness, pain, discomfort # Anxiety, depression, memory problems and speech problems" * The primary motor cortex which executes voluntary movements receives inadequate information due to insufficient and impaired activation by dopamine" Parkinson’s Disease - Treatments" * No known cure" * Complex nature requires a biopsychosocial approach to disease management" * Can be relieved by medications# Stimulate reception of dopamine by neurons to react as they would to dopamine# Converted into dopamine and mimic the role of dopamine" * One of the most commonly used and effective medications is L-dopa made from levodopa, a chemical that’s converted to dopamine by neurons" * Deep brain stimulation# Surgical procedure# Electrical stimulation of the brain# Conscious during surgery # Electrodes implanted in brain near basal ganglia# Try to block abnormal neural messages that cause motor symptoms" Eustress" * Positive psychological stress" * Feeling enthusiastic, motivated and active" * Typically short-term" * Can enhance performance" Distress" * Negative psychological response" * Feeling angry, anxious and irritated" * Short-term but can also persist for weeks, months or year if not addressed and managed" * Harmful effects" Stressor" * Situation, circumstance or any stimulus that’s perceived to be a threat or which causes and promotes stress" Stress" * A psychobiological process# Psychological - initial mental processes involved in the perception and interpretation of the stress# Biological - activation of the autonomic nervous system" Common signs of stress" Physical

Cognitive

Emotional

Behavioural

Increased blood pressure

Loss of self confidence

Apprehension/anxiety

Sleep disturbances

Headaches

Memory impairment

Feeling overwhelmed

Change in eating habits

How is stress a good thing (physiological changes)" * We release adrenaline - this means we’re more alert and able to concentrate" * Our pupils are dilated - we can see better and foresee danger" * Our glucose levels are increased - increased energy" * Heart rate increases - blood supply is distributed to our muscle giving us energy" Daily Pressures" * A lot of stress is from minor troubles that arise in day-to-day living# Having an argument with a friend# Waiting in line# Looking for keys" * They are things that annoy us and which can make us upset or angry" * They can happen on a regular basis or rarely" * The degree of effect varies" * The more daily hassles someone experiences - the more likely people are to have physical or mental health problems" * An accumulation of daily hassles can contribute more to physical and/or psychological ill-health than a single significant life event such as getting divorced or the death of a loved one" Common Daily Pressures Children and early adolescents

Middle-late adolescents

Adults

Having to clean your room

Conflicts with boyfriend or girlfriend

Concerns about weight

Being teased at school

Having your trust betrayed by a friend

Concerns about money

Life Events" * Change that forces us to adapt to new circumstances# Loss of a significant relationship/death# Beginning a new job# Changing schools" * These events are made by us as individuals and are the choices we make" * They can be positive and negative. Having a child - choice is positive but birth is a stressful period" Acculturative Stress" * The demands of adjusting to a new culture can be extremely stress-producing " * Acculturative stress can arise as a person adapts to these changes in a new culture" * Research findings indicate that belonging to an ethnic group or cultural minority group significantly increases the risk of developing stress-related physical or mental health problems# Might willingly relocate# Emigrate for better opportunities # Flee as refugees/asylum seekers" How to assist# * When society is accepting of ethnic and cultural diversity, acculturative stress can be reduced" * The ease of transition is also enhanced when the person has some familiarity with the new language and customs, advanced education and social support from friends, relatives and organisations formed by and for members of the cultural group" * The individual’s attitude is also important in determining the degree of acculturative stress" Major Stressors# * Extraordinary stressful or disturbing event for almost everyone that experiences it" * Can be a single event - victim of violent crime" * Can be ongoing and unrelenting - terminal illness" * Doesn’t have to be directly experienced. Can be a witness and still experience stress" * Usually they are a significant threat to individual’s physical or psychological wellbeing. Emotional reaction that may result in a difficulty in coping or functioning as the person normally does" Major Stressors that can lead to psychological trauma" * Acts of violence (terrorism, war)" * Natural disasters (bushfire, earthquake)" * Interpersonal violence (rape, suicide)"

* Involvement in a serious motor vehicle and workplace accident" * These cause strong emotional or physical reactions. Shock and denial are typical responses. Long-term we can experience flashbacks, unpredictable emotions, strained relationships and even headaches and nausea " We’re said to have physical, cognitive, behavioural and emotional symptoms to major stressors" * Catastrophes# * An unpredictable event that causes widespread damage or suffering" * Disruptive for an entire community" * Affects many people simultaneously and is out of their control. There’s usually no one to blame. In a human-made disaster, blame can be assigned to a system malfunction or negligence by someone# Bushfires, earthquakes and mudslides" * Amount of exposure, and whether it was 1st or 2nd hand - are highly related to future mental health problems" * How quickly support and aid arrives and how one’s social network is disrupted are all important for coping" Why does this cause stress?# * Close contact to victims" * Sensitive to environmental factors# Continue to hear news of the damage" * Strained interpersonal relationships" * Our social network may be disrupted" * Changes to thoughts and behavioural patterns# We may be worried about support" * Intense/unpredictable feelings and stress-related physical symptoms# We can’t stop thinking about the event# Anxiety, fear, re-experience events and constantly avoiding reminders" * Our stress reactions can last days or even weeks. We may have psychological and physical reactions" * Long-term - PTSD and ASD # Models of stress as a biological process " Biological Responses" * When we have a stressor we either confront it, run away or are paralysed in the face of danger# This is known as the FFF response# This response is controlled by the sympathetic branch of the autonomic nervous system" * It’s innate, involuntary and critical for survival. We’re energised to react to a threat" * Freeze is an adaptive response where both the sympathetic and parasympathetic responses are operating simultaneously" Fight-Flight-Freeze " * Adrenaline and noradrenaline increase respiration and heart rate but prolonged stress could lead to heart attack" * Glucose provides us with energy" * Long-term adrenaline can strain our cardiovascular system, leading to permanent changes in heart rate and blood pressure. This can increase the likelihood of contracting heart disease or having a stroke" Biological Responses - Role of Cortisol" * Cortisol is important as when it increases it causes the hypothalamus to trigger corticotrophin (CRH) - activating the pituitary gland - releasing adrenocorticotropic (ACTH) - and releasing stress hormones such as adrenaline, noradrenaline and cortisol " * Unlike the FFF response, the HPA axis takes significantly longer (seconds to minutes) to exert its influences. Its effects also persist for a much longer time (minutes to hours)" * This happens when we’re exposed to prolonged stress. Cortisol reduces inflammation and helps to repair muscles rather than continuing the ‘wear and tear’ on our bodies" * Cortisol maintains our blood-glucose levels (energises our bodies) and helps metabolism of fat, protein and carbohydrates " * BUT prolonged stress can suppress our immune system, making us vulnerable# This is because the activities of our lymphocytes (find and destroy harmful cells) and phagocytes (ingest and eliminate harmful cells) are reduced" * Elevated levels of cortisol is fed back to the hypothalamus to safeguard us"

* When the cause of stress is removed, the levels lower and the body returns to normal#

" General Adaptation Syndrome - Hans Selye 1930s" * There are 3 stages in GAS # Alarm reaction (shock and countercheck# Resistance# Exhaustion" * This is a biological model as it focuses on the physiological (our body and how it responds) response" * Selye found that everyone goes through all 3 stages and that the exhaustion stage is only reached if exposure to the stressor is persistent" * GAS is the body’s way of adapting and dealing with a perceived stressor" Alarm Reaction" * Shock# Realises there’s a threat# Temporary state of shock# Body reacts as if it’s injured# Low blood pressure and low body temp" * Countershock# Sympathetic nervous system activates# Release adrenaline, noradrenaline and cortisol to increase energy and resistance# Speeds up heart and respiratory system# Prepares for emergency response FFF" * This stage is a general defensive reaction to the stressor and results in a state of tension and alertness and a readiness to respond to the stressor" Resistance Stage" * Parasympathetic nervous system reduces heart/respiration rate" * Glucose continues, keeping the body prepared for action and increasing body’s stress tolerance" * If stress continues - we remain in elevated state of arousal with greater energy to deal with situation and adapt physiologically " * Continued adrenaline and cortisol can suppress the immune system, meaning we’re more likely to get colds, influenza or bacterial infections as our ability to fight disease has been weakened " * We may appear socially withdrawn, tearful or angry/moody" Outcomes of Resistance Stage" Successful

Unsuccessful

We can deal with initial stressor

We have not dealt with stressor

Successful

Unsuccessful

We have adapted to the stressor

Stress continues

Body eventually return to its normal balanced (homeostatic) state of functioning

Organism enters exhaustion stage

Exhaustion" * Body’s ability to meet demands of the stressor begin to decline as the person enters this stage as it hasn’t adapted" * Bodily biological resources have severely depleted. Resistance to stress has dropped significantly" * Increased likelihood of psychosomatic illness (combination of psychological, emotional and physical factors) as cumulative effect on organ systems and inhibition of immune system and disease such as ulcers, stomach pain, insomnia and migraines" * Cortisol helps to repair body but is also weakening it (‘wear and tear’)" Strengths and Weaknesses - GAS biological model" * Rich info about physiological processes" * Selye established the greater the intensity of stressor, the greater the physiological response" * Model mainly based on lab rats, limited model with humans and hard to generalise" * Rats’ responses to stress are less varied and less complex than humans" Lazarus and Folkman # * Working with people, L&F ...