Psychology - Lecture notes lecture 1-12 PDF

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Psychology: Lecture 1: 18TH July Psychological science Psychological Research What is psychology? Brain, behaviour, describe people, thoughts, feelings, personality, attitude, ability, achievement, Many different types of psychology eg; educational psychology where we learn to enhance learning Psych...

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Psychology: Lecture 1: 18TH July Psychological science Psychological Research What is psychology? Brain, behaviour, describe people, thoughts, feelings, personality, attitude, ability, achievement, Many different types of psychology eg; educational psychology where we learn to enhance learning Psychological processes within the nervous system Effect on natural environment and wellbeing Why treat Psychology as a science? Science can provide valid conclusions When less rigorous methods employed outcomes can be bad Public believe psychologists as they effect people’s lives in a positive way New reports the outcomes of psychology studies Theories are correct based on evidence Experimental Research Qualitative = describe behaviour = does not seek to establish cause and effect relationships (non-numerical) Appropriate methodologies depend on the types of questions you ask in your research Evidence summarised in numerical terms (quantitative) and is based on scientific method Eg: domestic violence - Quantitative = look at the number of incidents of domestic violence over time (maybe because of factors such as poverty) - Qualitative = take the time to talk to the victim (describing the situation using interview method)

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Lecture 2: 25th July Psychological Science Psychological Research What is a science: The canons of science? Determinism: - The world is orderly - Effects have causes – things that we think and do - Causes have effects - Eg: gravity, laws of physics, breathing What about behaviour? Identify the causes and effects of behaviours? Eg: sleeping through your alarm clock, what happens? why did you not awaken? Are these causes and effects consistent? Could be based on individual differences and past experiences The same event, the same time with the same key experience People on average report poorer mood on cloudy days than sunny days - If you ask people about the weather first effect disappears - Weather influences mood, but only until this is noticed that this is not a valid cue Empiricism: “from the horse’s mouth” Observing the world is the best way to learn about world But some things are difficult to measure Absence of evidence is not evidence of absence Although an accumulation of evidence can be useful Testability and Falsifiability: Closely linked to Empiricism Theories should be able to be tested Evidence supporting a theory should be able to be observed Evidence that would disprove a theory should be able to be observed (Falsifiability) Good theories should be easily falsifiable Worrying for psychology, but the good news is that because these theories are falsifiable, then we can move forward. Registered Replication Reports (RRR): a new trend in psychological science that facilitate research cooperation Add rules to allow theory to be falsifiable = which is what you want Power posing = fake it till you make it = might make you a little more confident because you believe in the theory however the science is not behind it Eg: testable theory = all swans are white, however go find a black swan Untestable theory = bad theory = unfalsifiable good theories should be easily falsifiable. In psychology Sometimes we accept that we are wrong Parsimony: We should prefer the simplest theory that explains all relevant data = explains more Fewer assumptions, more observable, most generalizable theory is better Two competinting theory = we want the simplest and most information theory not messy Traditional Medicine Theory: adding more of an ingredient increases the strength Why? Because there is more of the active ingredient

Homeopathy Theory: Diluting an ingredient makes it stronger 2

= parsimonious? Homeopathy = we have to develop extra assumptions and theory Parsimony in psychology: Lunacy. Does the full moon trigger emotional disorders? Full moon effect Theory: Full moon induces emotional disorder among some individuals Why? The moon’s gravitational forces change water flow in humans Which does? These flows of water might alter or trigger electrolyte or hormonal shifts in humans How would this affect mood?

No full moon effect Theory: Full moon has no effect on emotional disorders Why? The moons gravitational force is about “a drop of sweat” in strength after the earths is taken into account

Lunacy. Which theory do the data support? There is no scientific evidence that lunar cycles mood disorders (Rotton, 1985) Parsimonious explanation for a going belief in this myth is conformation

Why Experiments? Allow for manipulation of one variable Eliminate confounds Is logical fallacy Because we hold all else constant can compare when the variable is present or absent This allows us to make casual conclusions 3

Replicability very important Precision in manipulation important We want to make cause or claim about our work – try change the world eg: decrease poverty. Solution to poverty? Why do some people end up in poverty? Eg: Ice cream consumption correlates with drowning at beach does ice cream cause drownings? No related variable is hot weather (Third variable explanation) as it increases Ice cream consumption increases due to hotter weather and people wanting to go to beach increase therefore more likely to have more drownings The Measurement Process: - The quality of information depends upon how the data were collected and analysed - Characteristics of the process or phenomenon that we are interested in quantity or quality are called variables The measurement process…variables Independent (IV) hypothesised cause (manipulated) Dependent (DV) hypothesised effect (observed) Extraneous unwanted, uncontrolled influences on DV Confounding influences on the DV not separable from one or more levels of the IV you want to study Case: Is it important to eat breakfast before school? IV = Eat Breakfast/ No Breakfast DV = Score in a maths test Possible extraneous = some kids are better at maths than others / whether kids usually have breakfast in the morning. Possible confounding = hungry kids in the no breakfast group buying and eating lollies (high sugar before the test) Direct observation = usually applies to physical processes eg: Probe placed in neuron to measure voltage activity, temperature, blood pressure, height, number of children etc. For example: Insert an electrode into a facial muscle and measure the activation when someone smiles Show pictures of different facial expressions to the participant and find out if they smile automatically when they see a smiling face Extraneous Variables produce uncertain outcomes and conclusions = people vary in trait empathy and are less likely to mimic a smile if they are low on empathy Confounding variables may produce clear outcomes but certain conclusions = possible confounding is if there is no muscle activity in response to smiling then this might be because everyone participating in the experiment was low empathy Indirect Observation (more difficult) = it is easy to overlook the fact that we cannot directly observe or measure such things as motivation, peer pressure, learning or intelligence - In the social sciences, we often have to use indirect measures via operational definitions. Operational definitions are a way of indirectly measuring an abstract variable be observing what are believed to be effects on behaviour Hypothetical construct versus operational definitions Hypothetical Construct Hostility Intelligence Political attitude Personality

Possible operational Definition Fighting (how defined) Score on IQ test, GPA Political affiliation, opinions, morality BIG5/6 questionnaire

Does your proposed operational definition have reliability and validity? Reliability = the sscore obtained using your operational definition are reliable if they are reproducible and consistent Validity = A measure is valid when it measures what claims to measure 4

- Scores may be reliable but not valid How do you achieve reliability and validity? Depends to a large extent on the control of extraneous and confounding variables: Control group, placebo control, careful selection of participants (random selection and allocation to groups) Blinding conditions, matching, counterbalancing Why experiments? The purpose of experiments is to produce a statement of cause and effect backed up by empirical evidence In the design of the experimental procedure the goal is adequate control of extraneous and confounding variables that the effect of the IV manipulations upon the observation can be determined. An example experiment… Behaviour overserved = In a library where students studied during the semester they frequently reported having a headache Hypothesis = studying for a long period causes the headache Test of the hypothesis = record incidence of headaches for students who work in the library for each paper (300 level students are more likely to spend more time in the library). Expect more headaches with more time in the library Variables = IV = hours of studying (paper level), DV = frequency of headaches, Extraneous variable = presence of different numbers of migraine sufferers in 100, 200, 300 level students; general susceptibility to headaches; stress and anxiety across people, confounding variables = brighter lights on level 4 and 5 where 300 level students go more often. Progressively more stressed students at 300 level, 300 level student work harder and cause headaches, 300 level students are more likely older than 100 and 200 level students. If the result was = students at 300 level the most headaches Should we conclude: working for longer causes headaches, or working under poor lights cause headaches, or older students have more headaches, or being stressed causes headaches. - Good experimental control, and critical thinking about the data are always necessary in the experimental research. Summary - Psychology is diverse - Psychology research can be science - Four canons of science - Scientific methods in psychology - Samples vs populations - Operational definitions - Validity and reliability - Experiments

Lecture 3: 1st August Brain and Behaviour Biological Basis of Psychology 5

Reading: Brain and Nervous system

The Brain: A brief overview - The brain cannot store fuel, nor temporarily extract energy without oxygen (muscles can) therefore its continuously receives about 20% of the blood flow from heart. Many other parts of the body work on a supply and demand system. - It is most protected organ of the body, in a bony container, floats in fluids(csf) reducing its net weight, protected by the meninges (protective layers of thin layers of thin tissue - Protected by the blood-brain-barrier no free exchange between the blood and extracellular fluid of the brain.

Lateralisation of brain function Lateralisation means to one side – although the left hemisphere is usually a little larger than the right, the two sides of the brain are anatomical mirror image. But each hemisphere has a particular specialisation Distinction between localisation and lateralisation Localisation = visual functions are localised in the occipital lobes Lateralisation = control of the right foot is lateralised to the left hemisphere Both hemispheres are usually involved in tasks (synchronised through the corpus callosum, but each has a stronger role in some tasks than the other does 6

Hemispheres do perform separate functions Left: - Producing and understanding language - Controls right side of the body Right: - Perception and synthesis of non-verbal information (music, math, understanding spatial information) - Controls movement on left side of the body So, although their hemispheres are similar there are some functional differences - Sensory inputs and motor outputs mainly contralateral - Information available to both hemispheres via the corpus callosum - Left and right hemisphere strokes have different consequences

How is lateralisation studied? Correlate deficit with damage - For example, when the frontal lobe of the left hemisphere is damaged and the damage includes brocas area, then the patient may experience a speech problem known as brocas aphasia. Usually there is no speech impairment for damage to the same location of right hemisphere Wada technique (using sedative): inject barbiturate (usually sodium amytal) into the cerebral arteries of one hemisphere - Used to identify location of problem for epilepsy patients - Puts one hemisphere to sleep while the other continues to function - Assess the remaining functions - Reverse and repeat Use the unique properties of the neural pathways – especially those for vision - Each hemisphere receives input from both eyes but from the opposite side of space - The two sides of visual space are called left and right visual fields - Each eye therefore sees the whole of a scene both the left and right visual fields - Light from the right visual field reaches the left half of the back eye, and vice versa - Each half of each retina sends the information it receives to the hemisphere on that same side - Outcome = left visual field is sent to the right hemisphere, right visual field to the left hemisphere The visual field properties allow for the reaction-time (RT) studies in normal individuals Reaction time to particular stimuli is recorded by a computer E.g.: scientists look for evidence of faster RTs to verbal material that is sent first to the left hemisphere, either through a visual or an auditory route. In hearing the contralateral pathways are stronger than the ipsilateral pathways. Sometime simultaneous but different presentations are sent to the two eyes or the two ears (dichoptic viewing and dichotic listening) 7

Subjects more readily recognize the words flashed in the visual field contralateral to their dominant language hemisphere. This is because signals from each visual field are conducted directly to the contralateral hemisphere, before being conducted to the ipsilateral hemisphere through the corpus callosum

“Split-brain” individuals These were patients who had their corpus callosum, and sometimes other more minor neural pathways between the hemisphere, cut. The operations were done to prevent the spread of abnormal electricity activity (epilepsy) from one hemisphere to the other. Basic nervous system elements Like every other part of the body the nervous system is composed of cells Neurons are specialised cells that are the basic units of the nervous system Enormous amount of capacity for information processing

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Neuro Transmitters Action potentials = electrical impulses within a neuron = only allow for information to travel within a single neuron: e.g. an action potential has to travel the entire distance from your brain to your big toe to make it wiggle Communicate between different neurons uses chemicals called neurotransmitters Neurotransmitters are released at the end of the axon and are detected by the dendrites of other neurons. The name for the place where an axon meets with dendrites is called a synapse - Many substances mimic NTs: stimulants, tranquilisers, nerve gas, insecticides, poisons such as curare, alcohol and many other drugs affect the processes occurring at a synapse. - Substances that increase the effectiveness of an NT are called agonist, substances that decrease the effectiveness are called antagonists The two divisions of the autonomic nervous system The sympathetic NS - Regulates the body expenditure of energy - Prepares of body for cation: fight or flight = pounding heart, sweating, shaking, nausea - Effects includes: increased heart rate and blood pressure, pupil dilation, release of energy, inhibition of digestion, makes you sweat or blush The parasympathetic NS - Works in the opposite way 9

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Slows down body functions, converse energy, involved in digestion

Lecture 4: 8th August Consciousness States of consciousness 10

Philosophy of consciousness What is consciousness? Awareness, seeing the world from your perspective Bending the realms of consciousness: hemicortectomy, disorders of consciousness, surgical exchange of brain cells Awareness and Attention Consciousness = awareness - You are who you are by virtue of own personal awareness - There are things going on in you of which you are unaware – biological events you have no inbuilt sensor for - There are other things you do not choose to be aware of at a particular moment, but can become aware of – therefore your consciousness is often a matter of choice Attention = focusing conscious awareness (filtering out irrelevant stimuli) Components of attention - Orienting to sensory stimuli (turning sensory organs towards stimulus) + activating relevant parts of cortex for processing - Controlling behaviour and the contents of consciousness (how much to listen when someone is talking) - Maintaining alertness - Focused attention – tuning out other things - Sustained attention – controlling wandering - Divided attention – trying to follow two conversations at once - Alternating attention – switching back and forth rapidly - Turning attention away from present moment – day dreaming Limited attentional Capacity = attention is a limited resource. Cannot pay attention to everything The cocktail party phenomenon = When at a loud party you can focus on one conversation (selective hearing), if you here your name your attention snaps to the source, shows we process things unconsciously, attention snaps to salient information. Perspectives on consciousness: Freud and the Unconscious - Psychodynamic perspective - Sigmund Freud suggested that we have three levels of consciousness (conscious, preconscious, unconscious) Subliminal Priming - To what extent can you be influenced by something that you aren’t consciously aware of Contemporary understanding of consciousness Information processing mechanisms that operate outside awareness e.g.: implicit memory, procedural knowledge - The terms consciousness and working memory are often used interchangeably Functions of unconscious processes: - Fast and efficient processing - Adaptive response to environmental stimuli - Can operate simultaneously

Neuropsychology of Consciousness

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Split brain studies Studies with amnesiacs (recall vs recognition) Blind sight: People with damage to the central portion of the occipital cortex: are blind in the sese that they are unable to see objects placed before them and are able to provide partial information about the geometric shape of an object (blind sight)

Where is consciousness in the brain? Consciousness is distrusted throughout the brain - Hindbrain and mid brain are important for arousal and for sleep - Damage to the reticular formation can lead to coma - Prefrontal cortex is key for conscious control of information processing Circadian Rhythms: When the brain is active the moment by moment sum of the many positive and negative potentials is a low-amplitude, unsynchronised random EEG (Electroencephalogram) pattern Investigations into sleep are usually carried out in a sleep laboratory Sleeping and walking cycles are one of our biological rhythms. It is a circadian rhythm (CR) = about a day Temperature, another CR, is synchronised with the sleep cycle. We go to sleep as the body temperature begins to drop and waken as it begins to rise. Insomnia Inability to sleep Second most common medical complaint Cost hundreds of millions of dollars Many self-medicated with sleeping tablets Rem sleep characteristics Eyes move rapidly under lids Fingers or toes twitch EGG similar to wakefulness, cerebral blood flow and oxygen consumption increased Individual difficult to wakeup Motor output suppressed to the point of paralysis (muscles for respiration and eye movements exceptions) – knee jerk reflex absent If awaked during REM sleep will most likely report a dream Last about 20 -30 minutes but more prolonged as night progresses. We visit REM sleep 4-5 times/night Why do we sleep? Recuperative and evolutionary models may both be true to some extent – if rest is required for restoration it makes sense to rest when energy resources (food) are not available Repair and Restoration from wear and tear of daily life – growth hormone ...