allows designing interventions to fix the causal-effect (with other hypotheses /predictions)
General scope: need to apply across a variety of different settings
How reliable is research?
Construct validity: Am i measuring the right construct?
makes sure that events that occur in research setting actually correspond to the theoretical construct
The extent to which the independent and dependent variables used in research correspond to the theoretical constructs under investigation
IVs and DVs must correspond to the intended constructs, and they must not correspond to other constructs
There are infinitely many ways to measure psychological constructs
How to measure psychological constructs:
self-report measures: rate on a scale
observational measure: record actions
archival measures: see past trends
performance measure: test scores/speed/…
physiological measure: brain activity
Internal validity: can i draw the correct conclusions about causality?
extent to which it can be concluded that changes in the independent variable actually caused changes (not any other cause) in the dependent variable in a research study
dependent on the research design
Gold standard of establishing causality is an experimental design:
A research design in which researchers randomly assign participants to different groups and manipulate one or more independent variables.
Random assignment: The procedure of assigning participants to different experimental groups so that every participant has exactly the same chance as every other participant of being in any given group.
Manipulation: Intentionally varying some factor as the independent variable in an experimental research design
External validity: makes sure that we can make claims about more than just the people in a study (generalize)
extent to which research results can be generalized to other appropriate people, times, and settings
Biological psychology:
The human nervous system
Includes:
peripheral nervous system (PNS)
somatic nervous system: control what brain ask of the body
cranial nerves: Emerge directly from the brain
spinal nerves: Emerge from the segments of the spinal cord.
autonomic nervous system
parasympathetic nervous system: The “rest-and-digest” system, conserving energy and promoting routine body maintenance
sympathetic nervous system: The “fight-or-flight” system, preparing the body for intense physical activity or perceived danger.
central nervous system (CNS):
Stress
Three dimensions of stress:
Psychological stress
Sympathetic nervous system reaction to stress
Hormonal reaction to stress
Psychological stress response
Psychological stress = perceived stress
appraisal theory:
Our emotional and physiological response to an event is not determined by the event itself, but by our interpretation or appraisal of it
Stress is a transaction between an individual and their environment
Step 1: Primary Appraisal: interpretation of the stressors → if dangerous → step 2
Initial evaluation
“Am I in trouble?”
Three possible outcomes:
Irrelevant
Benign–positive
Stressful
Three stressful appraisal forms:
Harm/loss (damage already sustained)
Threat (anticipated harm/loss)
Challenge (possibility for mastery or gain)
Step 2: Secondary Appraisal: analysis of the available resources
“What might and can I do?” → if efficient → cause stress
Different coping options are evaluated:
Will it accomplish what it is supposed to do?
Can I apply a particular strategy effectively?
What are the consequences of using that strategy?
Step3: Reappraisal: pacing and learning
“How has the situation changed?”
Usually based on new information or as a result of cognitive coping efforts
Sympathetic nervous system reaction to stress
Increase quickly and dropping quickly right after
Neurons and neural activity:
Neurons communicate using electrical signals (action potentials)
Action potentials form the basis of all neuronal communication
At the macro level, the firing rate reflects transmission of information
Even during sleep, there is only a small, ~15%, decrease in energy use
Energy to the brain is supplied as oxygen and glucose (sugar)
How to measure neural activity? with subtraction method
Most common use of fMRI is to apply the subtraction method to identify brain areas related to certain cognitive functions
Example use:
Why do people remember some words but not others?
Participants learned lists of words
Needed to make recognition decisions
Measure activity for remembered vs. forgotten words
subtraction method: minus the 2 scans to identify the differences
Connectivity analysis
Measurement of neural activity asks which areas are active when engaging with a specific task
Connectivity analysis asks which areas influence the activity of other areas
Cognitive Psychology
Cognition is the set of mental processes the mind uses to acquire, represents, and processes information about the world.
Cognitive abilities:
learning
memory
attention
perception
problem-solving
decision making
reasoning
language
Cognitive psychology is the scientific study of how the mind acquires, represents, and processes information about the world
The defining feature of cognitive psychology is analyzing mental phenomena in terms of how the mind processes and represents information
The perspective and methods of cognitive psychology can be applied to all mental phenomena
Memory
Human memory is not precise, often it links related items and remember things that didnt exist
Schema: knowledge about what is typical of a given situation, event, location, etc
we forget things because:
Memory decay:
Memories naturally “degrade” over time
Retrieval failure: memory is there but we cant recall
Forgetting occurs due to the loss of available retrieval cues
Memory can feel like it is on the “tip-of-the-tongue”
With the right prompting, old memories can come back
Interference
Retrieval is competitive; memories interfere with each other
Target memory retrieval is blocked by competing memories
False memory: remember thing that didnt exist
Memory is a reconstructive process
We take whatever comes back to mind and fill in the gaps.
Retrieving a past event engages the same brain mechanisms as imagining a future event
Through the reconstruction process, memories can get distorted
Recipe for false memories: Source monitoring framework
People must accept that the suggested event is plausible
People must create contextual information for the event, such as an image and a narrative
People must commit a source monitoring error, wrongly attributing their memory construction to personal experience
fMRI used for energy consumption by brain based on oxygen
EEG used for
Remembering:
Make sure to encode the information. Attention is important
a random image is easier to be redrawn from memory if there is an “explaination” of the image to describe what going on
Meaningful information gets stored in LTM. Encode information on a deeper level through meaningful associations to improve memory (the level-of-processing effect)
example: “The old man bought the paint to color his cane” is much easier to rmb than “The old man bought the paint”
Understanding and organizing information to increase distinctiveness in memory. Example: using
acronyms
peg-word method
method of loci (location)
Memory retrieval is better if the retrieval context is similar to the one at encoding (the encoding-specificity effect)
learnt and recall when intoxicated is better than learn when intoxicated and recall sober
Memory retrieval is better if the mental process engaged at retrieval is similar to that at encoding (the transfer-appropriate processing effect)
depth-of-processing effect: participants just need to identify if they saw the word before
semantic encoding (does it have?) is better than shallow encoding (does it rhyme with?)
Transfer-Appropriate Processing (Rhyming Recognition): participants might be asked to recognize the target words based on their sound
shallow encoding (rhyme) is better than semantic encodiing
Better than relearning? Tests, even without feedback (the testing effect)
Add gaps between study sessions (the spacing effect)
more times studying is better than long hours
Why video games are so addictive:
Loot boxes
Behaviorism (skinner box)
Variable ratio reinforcement schedule: known to lead to highest consistency
superstitious beliefs: belief that an action influences random chance
Daily tasks: “Fixed interval reinforcement schedule” guarantees rewards and avoids long streaks of frustration
Reinforcement thinning (gradually decrease the frequency of reinforcement): leads to most consistent behaviors
Development psychology
what is development:
development = qualitative change, something becoming different from before
examples:
physical appearance
cognition
identify
morality
performance
Development implies changes in behavior that have the following characteristics:
Aimed at a higher level
Aimed at a final state
Qualitative in nature
Correlated with age
Universal (i.e., not culture-specific)
Modern understanding of development:
Development as a life-long process
Development is multi-directional:
same point and develop to different points
same point can be developed from different pathways
development can be reversible
Development as gain and loss
Development as systemic change
Development as probabilistic epigenesi
Epigenesis: Idea of the unfolding of predetermined predispositions (nature)
Probabilistic epigenesis (Gottlieb, 1991):
Predetermined predispositions unfold with a certain probability, as a function of the environment and experiences (nurture)
can be inherited, but not be learned: nativism
can be learned but not be inherited: empiricism
Nature vs Nurture & heritability
How much of our behavior/personality is shaped by our “blueprints” (genes) versus our “construction” (environment)?
Behavioral genetics is the empirical science of how genes and environments work together
Nature: Genetic predispositions (nativism)
Nurture: Experience and environment (empiricism)
Modern view: It’s not “either/or” but how they interact (recall: probabilistic epigenesis)
Heritability (h^2)
statistical estimate of how much of the variation in a trait within a specific population can be attributed to genetic differences.
Formula: h2=Var(G)/Var(P)=Var(G)+Var(E)Var(G)
Var(G): Genetic variance
Var(G)=Var(A)+Var(AM)+Var(D)+Var(I)
Var(A): additive variance, 50% from each parent, gene expression independent from each other, explains similarity between direct descendants
Var(AM): assortative mating variance, people are paired in selection process (assortative mating) → leads to similarity between children and parents
Var(D): dominance variance, Influence of parents’ genes can be affected by gene dominance
Var(I): epistatic (gene-by-gene interaction) variance, various genes interact with each other
Var(P): Total phenotypic variance (Total differences we see)
Var(P)=Var(G)+Var(E)
Var(E): variance in environment
Var(E)=Var(C)+Var(e)
Var(C): shared environmental variance, shared between siblings and family members(finances, religion,…)
Var(e): unique environmental variance, unique to individual
Interpreting h2 Values
h2=0: Genes explain none of the differences.
Example: If you study a group of clones (0 genetic variation), any difference in their IQ must be 100% environmental.
Var(E) is large
h2=1: Genes explain all of the differences.
Example: If you raise different people in a perfectly identical environment (same food, same school, same parents), the only reason they differ is their genes.
Var(G) is large
0<h2<1: The reality for most psychological traits (personality, intelligence). Both nature and nurture contribute to the variance.
Research Methods: How do we estimate h2: To separate genes from environment, psychologists use two main strategies:
Method 1: Constant Genes, Varying Environment
Twin Studies: Compare Monozygotic (MZ - 100% same genes) vs. Dizygotic (DZ - 50% same genes) twins.
If MZ twins are much more similar than DZ twins on a trait (like Extraversion), heritability is likely high.
Method 2: Constant Environment, Varying Genes
Adoption Studies: Compare children to their biological parents (share genes) vs. their adoptive parents (share environment).
If a child’s personality matches the biological parents more than the adoptive ones, it suggests a strong genetic component.
Crucial Distinction (Science vs. Everyday):
Everyday mistake: Thinking h2 tells you what % of your trait is inherited (e.g., “I am 60% my dad’s height”).
Scientific reality: h2 describes groups, not individuals. If height has an h2 of .80, it means 80% of the differences in height among people in that group are due to genes.
Attachment
Contact comfort: monkey prefers cloth doll to wire doll even though its fed from wire doll
3 main attachment styles:
Secure: from responsive care giving
I find it relatively easy to get close to others and am comfortable depending on them. I don’t often worry about being abandoned or about someone getting too close to me.
Avoidant: from unresponsive to child’s needs
I am somewhat uncomfortable being close to others; I find it difficult to trest them completely, difficult to allow myself to depend on them. I am nervous when anyone gets too close, and often, love partners want me to be more intimate than I feel comfortable being.
Anxious–resistant: inconsistently responsive to child’s need
I find that others are reluctant to get as close as I would like. I often worry that my partner doesn’t really love me or won’t want to stay with me. I want to get very close to my partner, and this sometimes scares people away.
Parenting styles
Low expectation/control
High expectation/control
low warmth/responsiveness
uninvoled
authoritarian
high warmth/responsiveness
permissive
authoritative
Child outcomes
Secure children likely to…
Have better peer relationships
Be better evaluated by teachers
Persist on challenging tasks
Insecure (avoidant) children likely to…
Be classified as bullies
Have difficulty making and maintaining friendships
Attachment and relationship functioning
higher security:
more satisfying relationships
less conflict
more enduring relationships
more likely to provide support to partner in times of distress
Personality and social psychology:
examples:
temparement
intelligence
influence
attraction
stereotypes
What is personality:
Controversial
some common features
relatively permanent/persisting features
comprises of characterisics unique to people
give consistency and individuality to person’s thoughts, feeling and behaviors
”traits”: individual differences in behavior, consistency of behavior over time, and stability of behavior across situations
Each person, though like others in some ways, has a unique personality
What is social psychology:
the study of person in different situations (external context)
study of person in an internal context → personality
