Psychology Lecture Notes PDF

WEEK ONE - Psychology’s Progress to Becoming a Science What is psychology? - Psychology is the scientific study of the mind, brain and behaviour - Not easy to define - A discipline involving multiple levels of analysis: *-> with lower levels being biological (ex. Brain structure or behav...

WEEK ONE - Psychology’s Progress to Becoming a Science What is psychology? - Psychology is the scientific study of the mind, brain and behaviour - Not easy to define - A discipline involving multiple levels of analysis: *-> with lower levels being biological (ex. Brain structure or behaviour) -> high levels are psychological (ex. Thoughts, feelings, emotions) -> highest level social cultural influences (ex. relating to others and personal relationships) Challenges in the field of psychology Behaviours are difficult to explain because: 1. They are multiply determined - caused by many factors (ex. Going through a divorce, early life experiences) 2. Psychological influences are rarely independent of one another (ex. Inability to pinpoint factors occurring in an individual facing anorexia -> Individual could be perfectionist, gym) 3. Individual differences prevent global explanations of behaviour 4. Reciprocal determinism (Albert Bandura) (Others behaviour can influence others) 5. Cultural differences also limit generalisation about human nature and behaviour (ex. Different cultures can explain the same phenomena) What is science? - Science is an approach to evidence 1. Observations - Naive realism is the belief that we see the world exactly as it is, which may sometimes deceive us 2. Testing/examination 3. Decision to accept/discard Theory and hypothesis *What is scientific theory - General explanations - Accounts for existing data and findings - Able to generate novel & testable predictions *Hypothesis - Specific predictions derived from these explanations A Good Scientist *engages in bias-free practice: 1. Awareness of bias - Confirmation bias -> “once you have a hammer, everything starts looking like a nail” - Belief perseverance -> “don’t confuse me with the facts”  2. Attempts to avoid/prevent bias - Adopts scientific methods and procedures 3. Recognizes they may be wrong - Open to revision - Avoids making definitive conclusions to “prove” “My data suggests… or support… or raise the possibility that…” Scientific Vs. metaphysical: - Scientific claims can be tested - Metaphysical claims can’t be tested scientific methods (ex. Unable to prove if god exists) - Both are respectable and important… just different Science deals with testable claims, while Religion deals with untestable with data Science deals with nature -> religion does with moral values Science vs. Pseudoscience Pseudoscience: - An imposter of science (i.e., astrology, sine self-help books, etc) - Different from metaphysical claims - Makes claims that can be tested Why is it important to distinguish scientific claims from pseudoscientific claims? - Provides us with misinformation and misguide us - We are often convinced of their accuracy despite the lack of (or presence of weak) supporting scientific evidence - Popular and widespread beliefs are not necessarily accurate or supported by science Warning signs of Pseudoscience Over Reliance on anecdotes - Hard to verify - Difficult to generalise - Fail to inform about cause-and-effect relationships - (ANECDOTES ARE NOT SCIENTIFIC EVIDENCE) Meaningless psychobabble Talk of “Proof” instead of “evidence” Separating science from pseudoscience - Avoids logical fallacies (traps in thinking that can lead to wrong conclusions) when evaluating claims: 1. Emotional reading fallacy - refers to all the times regarding whether a claim is valid or not Ex. “I refuse to believe the idea that vaccination protects children from disease because it makes me really sad to imagine my child crying over a getting a vaccine” 2. Bandwagon Fallacy Ex. “Lots of people I know believe in astrology, so there’s got to be something to it” 3. Not Me Fallacy  Ex. “My psychology professor keeps talking about how the scientific method is important for overcoming biases. But these biases don’t apply to me, because I’m objective” *Bias blind spot - we are unaware of our own bias but are aware of others biases Why Are We Drawn to Pseudoscience? - Our brains tend to find sense in nonsense Patternicity -> tendency to see meaningful patterns in random stimuli - Provides a sense of control (hence, comfort) over the uncontrollable and predictable Dangers of Pseudoscience: 1. Opportunity cost - letting go of an opportunity because you believe in a pseudoscience treatment instead 2. Direct harm 3. An inability to think scientifically as citizens Scientific thinking is the best safeguard against error Scientific Thinking Scientific scepticism: evaluating all claims with an open mind, but insisting on persuasive evidence before accepting them - Different from cynicism - Willingness to change one’s mind when confronted with persuasive evidence that challenges one;s preconceptions - Unwillingness to accept claims on the basis of authority alone Hallmark of scientific scepticism: Critical thinking or scientific thinking 6 principles of scientific thinking Scientific thinking principle #1: Ruling out alternative explanations Is this the only good explanation for this finding? Are there any alternative hypotheses that could explain this pattern of data? When evaluating a psychological claim -> have we excluded other plausible explanations for it? Scientific Thinking #2: Correlation vs. causation Correlation? Variable? Correlation is not causation ○ “Babies who cry a lot are often in households with dogs who bark a lot. Therefore, dog barking causes babies to cry” Can we be sure that dog barking causes babies to cry? Dog barking -> baby crying? Baby crying - dog barking? Trains -> baby crying and dogs barking (Called third variable problem) - trains are the confounding/third variable (THE THIRD VARIABLE IS ALWAYS AFFECTING THE RESPONSE - Ex. If someone conducted a study and concluded their findings, however did not take into conclusion sex differences which can affect results) Scientific Thinking Principle #3 Falsifiability Scientific claims are falsifiable - Being falsifiable means the theory or the claims could be wrong if there is no evidence to support it, or if the evidence is invasive ○ Theory 1: “hugging infants can make them sleep better or not” ○ Theory 1. Revised: “Hugging infants for 3 hours each night before bed, will make them sleep straight until the morning; hugging infants for 1 hour each night, will make them wake up less during the night; & not hugging infants at all before bed, will make them cry all night ○ Scientific theories take risks (risky prediction) ○ In summary, you have to ask if another claim can be disproven (If it can it is falsifiable) Scientific Thinking principle #4: Replicability *What factors may explain why a study’s findings are not replicated by others who attempt to replicate it? - Findings of the original study may have been wrong - Later findings may be wrong - Samples (or participants) are not representative of one another - Other differences in study design and methodology *Researches other than the original team must replicate the findings Scientific Thinking Principle #5: Extraordinary claims - Is the evidence as strong as the claim? - Extraordinary claims require extraordinary supportive evidence Scientific Thinking Principle #6: Parsimony (Aka Occam’s Razor) Parsimony -> logical simplicity Good researchers use this helpful rule-of-thumb to provide parsimonious explanations Are there simpler explanations that can account for the data equally well? WEEK TWO - Research Methods History of Psychology - Influenced of spiritualism - Possessed by evil spirits - The movement of the moon & stars (‘Luna’) Social Stigma Typical Vs. atypical - Use this language Normal Vs. abnormal - Avoid using  ○ “Psychological disorders continue to carry a substantial stigma in our society. To be anxious or depressed is to be weak and cowardly. To be schizophrenic is to be unpredictable and crazy. For physical injuries in times of war, we award medals. For psychological injuries, the unfortunate soldiers earn scorn. Often, someone with psychological disorders does not seek health care for fear that a co-worker may learn about the problem. With far less social support than physical illness, people have less chance of full recovery.” * How do past historical conceptions of atypical behaviour influence present-day perspectives History of Psychology continued - Indistinguishable from philosophy - William Wundt -> first psychological laboratory in Germany - Marks the beginning of psychology as a science Major Theoretical Viewpoints - Behaviourism - Cognitivism - Psychoanalysis Behaviourism - Uncovering the general laws of learning by studying observable behaviour - John B. Watson - B. F. Skinner - Behaviour can be strengthened or weakened depending on it’s consequences - Reinforcement - Anything that strengthens a behaviour (reward) - Punishment -> relatively ineffective in the long run - Black box psychology: represents conscious awareness/unable to identify why an individual acts the way they do ? Input Output (Possible consequence) (Observable behaviour) Watson & little Albert - Among the first experiments to produce fear of an object that was previously not feared - Unethical based on today’s standards” Did not remove the fear Did not follow-up Pavlov’s Classical Conditioning Before learning: Unconditioned stimulus & unconditioned Response After learning: Conditioned Stimulus & Conditioned Response Cognitivism - Cognition - Cognition psychology - Peeking inside the black box *Different interpretation for every individual - Jean Piaget - Cognition neuroscience (exams brain function and thoughts) & affective neuroscience (relation between emotions and brain function) Cognition Input Output (Possible consequence) (Observable behaviour) Psychoanalysis - Sigmund Freud - Breuer - Unconscious mind - Part of our mind that is outside of our awareness - Freudian slips - Slips of the tongue carry symbolic meaning - Great emphasis on early life experiences - Critics: Freud’s theories & ideas, which rely on unconscious processes, cannot be falsified Nature-Nurture Debate - John Locke - The mind = Tabula rasa at birth (We are born as a blank slate) - Behaviour genetics research - Some genetic makeups make some individuals vulnerable to certain conditions - Both genes & environment play significant roles in most behaviours Free-Will Determinism Debate - To what extent are our behaviours freely selected than caused by factors outside of our control? Determinism: ○ Free-will is an illusion ○ Behaviours are generated automatically, without conscious awareness ○ B.F. Skinner Basic Research: Exams how the mind works Applied Research: How we can use basic research to solve real world problems 2 Types of Thinking - Type 1 thinking or “intuitive thinking” Ex. Meeting someone new at a party and you instantly dislike someone based off first impression Quick, reflective, doesn’t require much mental effort - Type 2 thinking or “analytical thinking” Ex. After thinking about the person more, your original thought could change based on reflection of person Slow, reflective, takes mental effort  - New Skill: analytical thinking -> intuitive thinking - Research design make use of the power of analytical thinking: - Ensure we consider alternative explanations Generalizability - Population - Refers to all people - Sample - Group of people that are chosen to be included in a research - Participant - each individual person in a sample - Representative sample through random selection - Large & randomly selected sample (hence, representative sample) is ideal - If not possible -> a smaller random sample *A Representative sample represents the population Evaluating Measures: Reliability - Is our measure reliable? - Reliability -> consistency of measurement - Test-retest reliability - determines if techniques of testing are reliable over time - Inter-rater reliability - The extent of different people who conduct an interview or make a behavioural example agree on what they are measuring Validity - Is our measure valid? - Validity -> extent to which a measure asses what it claims to measure Reliability & Validity - Reliability is necessary for validity - because we need to be able to measure something consistently over time - But, reliability does not guarantee validity Replicability & Reproducibility Replicability -> Ability to duplicate the original findings of a study using new data from new participants Reproducibility -> Ability to review and renanalyze the data from a study and find the same results (able to reanalyze the data from previous/original researcher) Open-Science Movement - Replicability crisis - Open-Science movement - Sharing datasets in public research archives - Attempt to replicate before exploring new questions - Preregistering one’s research (Hypotheses, design, analysis plans, etc.) - Merely publishing sound science in scientific journals - Combats against the “file drawer problem” - More emphasis on patterns of findings across studies WEEK 3 - Research Methods 2 types of variables - Variable -> a quality that differs and can take different values for different people - Independent variable -> a variable that is expected to influence the other variable (Etc. experimenter manipulates to see effects on the independent variable) - Dependent variable -> the variable that is influenced by the independent variable (i.e, always what we measure) - Manipulation Hypothesis Is the hypothesis testable? ○ Ex. People who laugh more have lower levels of anxiety than people who laugh less Research designs - Naturalistic observations - Case studies - Experimental - Correlational Naturalistic observations Studying behaviours in “real world” settings as they naturally occur with no attempt to study (Ex. Advantages: ○ We can understand a range of behaviours as they naturally occur ○ We can measure “true” behaviours ○ Avoids social desirability bias ○ High in external validity Disadvantages: ○ Slow progress ○ Low in internal validity (Unable to make cause and effect conclusions) ○ If people are aware of being observed Case Studies In-depth examination of the life of one person Interviewing the person or people that know them, analysing writings, etc Advantages: ○ Researchers are able to find out about personality in great detail ○ Formulate a general hypothesis that can be tested on a larger sample ○ In-depth knowledge about a rare phenomena  Disadvantages: ○ Results can never be generalised ○ Cannot establish causality *The only research that can create cause and affect studies are experimental studies Experimental methods Used to determine causality -> whether one variable (independent variable) causes another (dependent) variable I.e whether a drug (independent) variable causes memory enhancement (dependent variable) Placebo effect - Whenever there's a change in someone's behaviour simply because someone is expecting a change (Latin phrase: “I shall please”) - (EXPECTATION OF GETTING BETTER) Experimental group (drug) (testing effects) Control group (no drug) - no manipulation (to see the effect that hasn’t been manipulated) Placebo control group sugar pill (Placebo) - Placebo effect (to make sure the study is not influenced by the placebo effect Nocebo effect -> “to harm” (EXPECTATION OF HARM) Harm resulting from the mere expectation of harm (Opposite of placebo effect) Between-subject Design Needs to meet 2 key requirements: ○ 1. Random assignment of participants to conditions -> Manipulation across groups ○ 2. Manipulation of an independent variable -> Random assignment (randomization) Does a drug (Independent variable) cause memory enhancement (dependent variable)? Within-Subject Design 2 Key requirements: ○ 1. Manipulation of independent variable(s) -> manipulate within group ○ 2. Ensuring equality between participants in the different experimental conditions -> counterbalancing Experimental methods Random selection vs. random assignment Blind and double-blind studies Blind -> Being unaware whether one is in the experimental or control group ○ Avoid the placebo effect Double-blind -> neither researchers nor participants are aware of who is in the experimental or control group Experimenter expectancy effect or rosenthal effect  ○ Unintentional (When the tester unintentionally influences the study) ○ Confirmation bias Experimental methods cont’d Advantage: ○ Can establish relationships between variables Disadvantages: ○ Cannot identify relationships between variables as they occur naturally in everyday life - Cannot study behaviours as they naturally happen from a participant because of changes in setting, etc ○ May be impractical or unethical in some cases ○ Demand characteristics (Participants guess what the goal of the study) Telling participants a Cover story in order for the participant not to know what the goal of the study is “Distractor” tasks or “filler” Correlational studies Determining whether there is a relationship between two variables, without manipulation/intervening in any way Examines the relationship between variables as they occur naturally Correlation coefficient (-1 to +1) 0 means no relationship exists Positive correlation - As self-esteem decreases, happiness decreases - As self esteem increases, happiness increases Negative correlation - As self esteem increases, happiness decreases - As self-esteem decreases, happiness decreases Summary of Correlational studies Is there a relationship between self-esteem and happiness? - Strong “+” relationship between self esteem and happiness - Moderate “+” relationship between self esteem and happiness - Weak “-” relationship between self esteem and happiness Absolute value is the number Correlation studies Advantages: ○ Examines the relationship between variables as they occur naturally (no manipulation involved)  Disadvantages ○ Not designed to identify causal relationships (Directionality problem; third variable problem) *correlation does not indicate causation When to use which method? Each design has strengths and weaknesses that make it more/less suitable for specific research questions The research design choice depends on the research question and the goals of the research Strength of one design may be the weakness of another Provide complementary methods for exploring human personality Class activity Research question: Are individuals with AUD less happy compared to individuals without AUD Goal: To generalise our findings to all who have AUD YOU CAN USE CORRELATIONAL STUDIES TO DETERMINE THIS Ethical concerns REB - Research Ethics Board Must weigh scientific knowledge over potential harm to subjects Informed consent ○ Informed consent gives: Duration of the study Potential risks and discomfort Volunteer participation and right to withdraw Debriefing - is a process which the researchers tell the participant exactly what happened Decception ○ Deception is justified only when: Can’t perform without the deception Use of deception doesn't negatively affect the rights of the participant Research does not involve a medical or therapeutic intervention *Debriefing is emphasised when a study uses deception Statistics Descriptive statistics Inferential statistics Descriptive statistics Describe data Central tendency -> measure of the “central” scores in a dataset (where the group tends to cluster) Mean (Average) number of participants (5): ○ 78 + 110 + 78 + 100 + 94 / 5 = (92)  Median (which number falls in the middle): ○ 78 78 94 100 110 (94) Mode: ○ 78 Descriptive statistics FIRST PIC: MEAN SECOND AND THIRD PIC: MEDIAN OR MODE OUTLIERS SCORE OUTSIDE OF THE OTHER SCORES Descriptive statistics cont’d Variability Range -> difference between the highest and the lowest scores Standard deviation -> the average amount that an individual data point differs from the mean Inferential statistics (How confident we can be to generalize everyone in the population) Statistical significance -> the probability of obtaining our finding merely by chance is small Individuals with ASD have more cortical folding than individuals with ADHD (p nerve cell specialised for communication ○ 86,000 neurons in the brain Intercellular communication -> Each neuron makes tens of thousands of connections with other neurons ○ 160 trillion connections in the brain The subcomponents of the neurons Cell body (soma) -> contains the nucleus Nucleus -> manufactures proteins Dendrites -> receive information (or signals) from other neurons, & pass it to the cell body Axons -> sends the information (or signal) to other neurons Steps of Signal transmission Spherical sacs containing neurotransmitters chemical messengers neuron use to communicate with each other 3. Axon terminals release neurotransmitters into a gap (synapse) through which information is exchanged between neurons (i.e, received by receptors of the dendrites of nearby neurons) *VIDEO on steps of signal transmission: 2 minute neuroscience synaptic transmission Reuptake -> a means of recycling neurotransmitters Receptor sites -> Locations that uniquely recognize a neurotransmitter (Receptor sites are specialised only certain types of neurotransmitters) Neurotransmitters *The most common (in CNS) Glutamate ○ Excites neurons (increases the odds that they will communicate with other neurons) ○ Associated with enhanced learning & memory ○ However, if too elevated -> may continue to psychological disorders (i.e, schizophrenia) GABA (Gamma-aminobutyric acids) ○ Inhabits neurons (decreasing neural activity) ○ Certain drugs bind to GABA to treat anxiety, insomnia, depression, & epilepsy Neurotransmitters cont’d  Monoamine neurotransmitters ○ Norepinephrine ○ Dopamine Motivation & rewarding experiences that occur when we seek out or anticipate goals ○ Serotonin Ex. Psychoactive medication (drugs) Myelin Sheath Myelin Sheaths speed the transmission of electrical signal down the length of the axon Nodes -> gaps along the axons (electrical signal does not stop between the nodes) Myelin sheaths are created by oligodendrocytes which are a type of glial cells ○ Which are a type of glial cells Damage to myelin can disrupt the efficiency of signal from travelling down the axon -> physical or emotional symptoms (i.e, multiple sclerosis) How much of our brain do we use? The 10% myth Neuroimaging studies -> All brain regions become active on brain scans at one time or another: ○ When engaging in different activities & generating different thoughts, feelings, or perceptions ○ Even at rest, brain activity continues (i.e., not engaging in an activity) Losses of small regions of certain parts of the brain can cause permanent losses of functions or show subtle changes in behaviour Major Structures of The Brain Different brain regions serve different functions ○ Which interact with one another to generate our thoughts, feelings & behaviour The brain is a highly interconnected web of networks and circuits Cerebral cortex Outermost layer of the brain Gyrus (fold) & sulcus (groove) Folds are not random! Every healthy human brain has similar folds & grooves on the cortex Specialised functioning -> analyses sensory information & higher brain functions Cerebral Hemisphere 2 hemispheres: ○ Right hemisphere ○ Left hemisphere Corpus callosum -> large bundle of fibres connecting the 2 cerebral hemispheres Lateralization -> cognitive functions that rely more on the hemisphere than the other Brain produces a crossing over for movement The cerebral cortex 4 lobes: ○ 1. Frontal lobe ○ 2. Parietal lobe ○ 3. Temporal lobe ○ 4. Occipital lobe Frontal lobe Performs executive function that coordinates other brain areas (motor planning, language, decision making, reasoning, judgement) Central Sulcus -> sulcus that separates the frontal lobe from parietal lobe Motor cortex -> responsible for voluntary body movement Prefrontal cortex -> responsible for thinking, planning, language Broca’s area -> responsible for speech production Parietal lobe Touch & perception Primary sensory cortex -> sensitive to touch (pressure, pain, temperature); receives information about sensations Spatial perception -> Track objects’ locations and shapes, guides our attention when we want to act Hemispatial neglect Temporal & occipital lobes Temporal lobe: hearing, understanding language, & memory Auditory cortex - allows us to recognize words and the sounds Wernicke’s area -> responsible for understanding speech Fusiform face area Occipital lobe contains the visual cortex Subcortex Structures Basal ganglia -> help to control movement Limbic system -> “emotional centre” of the brain ○ Thalamus ○ Hypothalamus ○ Amygdala ○ Hippocampus Limbic system Thalamus -> sensory relay station Hypothalamus: ○ Responsible for regulating and maintaining bodily states by influencing hormone levels ○ Oversees hormone release and autonomic nervous system ○ Plays an important role in motivational behaviour (helping to regular hunger & thirst) Amygdala -> responsible to modulate memories based on feelings  ○ Pays attention to emotionally impactful stimuli and helps us remember wheat triggered our emotions ○ Fear is the most studied emotion ○ Hippocampus -> responsible for conscious memories for facts, events, and spatial memory Cerebellum “Little brain” Our sense of balance Helps us coordinate movement Helps us learn motor skills Brainstem Contains 3 parts: ○ Midbrain ○ Pons ○ Medulla Brainstem: Midbrain Movement Tracking of visual stimuli Reflexes triggered by sound Brainstem: pons Triggering dreams Connects the cortex to the cerebellum Brainstem: medulla Regulates basic vital functions: ○ Heartbeat ○ Breathing ○ Etc. Controls nausea and vomiting Serious damage to the medulla can cause brain death Grey matter and white matter Gray matter (or cerebral cortex): contains cell bodies and dendrites of neurons (appear darker) White matter: contains axons and myelinated sheaths (appears lighter) Protection against injury Cerebrospinal fluid (CSF): ○ Cushions the brain against injury ○ Contained in the cerebral ventricles Meninges: ○ Thin layer of membranes around the brain and spinal cord Neuroplasticity  Ability of the brain to change over time ○ In response to learning, treatment, or damage Possible ways neuroplasticity can occur: ○ Creating new synapses -> synaptogenesis ○ Strengthening existing synaptic connections ○ Structural neuroplasticity -> change in the shape of neurons, or number of dendrites Neuroplasticity cont’d Synaptogenesis -> formation new synapses Pruning (synaptic pruning) -> death of neurons and retraction of axons to remove connections that are not useful ○ Fine-tuning of neural connections -> “use it or lose it” notion during early childhood Pruning streamlines neural organisation, enhancing communication between brain regions Myelination -> axons are insulated by myelin sheaths Neuroimaging techniques Different neuroimaging techniques can be used to study: ○ Brain structure and anatomy ○ Brain activity ○ Brain connectivity MRI scans Advantage: Non-invasive procedure Brain structure and brain function (FMRI) can be studied Disadvantage: ○ Very loud ○ Enclosed space PET scans Measures brain activity Radioactive substance is injected Disadvantage: invasive procedure due to radioactive substance Brain stimulation techniques Deep brain stimulation (DBS) -> neurosurgical procedure that implants electrodes within the brain to provide direct electrical stimulation Transcranial Magnetic Stimulation (TMS) -> Strong magnetic fields applied to the skull to enhance or interrupt brain function ○ Non-invasive Behavioural Genetics methods A scientific approach which examines the influence of nature and nurture on psychological traits Heritability -> percentage of variability in a trait across individuals that is the result of genes  Phenotypic variance -> observed individual differences (i.e., height or personality) Genotypic variance -> individual differences in total collection of genes possessed by each one of us Behavioural Genetics methods cont’d Nature-nurture debate Teasing apart the contribution of genes and the environment: ○ Family studies ○ Twin studies ○ Adoption studies Family studies If a trait is highly heritable … family members with greater genetic relatedness should be more similar to each other than family members who are less closely genetically related But.. family members also share the same environment Thus, findings from family studies are never definitive Twin Studies Two types of twins: Monozygotic (MZ) and dizygotic (DZ) Estimates heritability by examining whether identical twins are more similar to each other, than fraternal twins are, in any personality trait or physical characteristic If identical twins are more similar than fraternal twins, this provides evidence of heritability Adoption studies Examines environmental influences Examines genetic influences