Unit 0

Page 1 — Intro to Psychology

Psychology is defined as the scientific study of behavioural & mental processes.

Why psych uses science

• We cannot always trust common sense or intuition

• Psychologists use:

  • observation

  • experiments

  • data

  • research

• Scientific attitude

  • Curiosity

  • Skepticism

  • Humility

• Critical thinking

Why Intuition can be wrong

Hindsight bias

• Believing after something happens that you "knew all along"

• Ex: after a team wins → "I knew they would win"

• We're much better at explaining results after they happen than predicting them beforehand.

Overconfidence

• Thinking we know more & are more accurate than we actually are

• We are often more confident than correct

• Ex: thinking a task will take 10 sec, but it actually takes 3 min

Seeing patterns in random events

• Humans naturally try to find patterns even when events are random

• Ex: coin flips

Confirmation bias → we disregard what we don't believe

• looking for information that supports what you already believe.

• Ignoring evidence that could prove you wrong

Page 2 — Psychological Perspectives

A point of view psychologists use to explain behaviour

8 perspectives

1. Evolutionary

• behaviour explained by evolution/natural selection

• Focus: survival + reproduction

• Ex: fear helped ancestors survive

2. Biological

• behaviour explained by the brain or body

• Focus: genes, hormones, neurotransmitters, nervous system

• Ex: depression linked to brain chemistry

3. Psychodynamic

• Freud: behaviour is influenced by the unconscious mind, childhood experiences & repressed conflicts.

• Developed psychoanalysis (set of psychological theories & a talk therapy method) we repress to our unconscious mind

• Drawing & therapy

4. Behavioral

• Watson: psychology should study observable behavior

• Pavlov: showed behavior can be learned through classical conditioning (make an automatic connection between neutral environment signal & a naturally triggering reflex)

• Focus: rewards, punishments, learned behaviour

5. Humanistic

• Maslow: people are motivated to reach their full potential

• Rodgers: Free will, personal growth, ability to improve.

6. Cognitive

• Focus: thinking, memory, perception, problem solving

• Piaget: how children's thinking developed

• Vygotsky: learned thinking develops through social interaction

• Bandura: people can learn by observing others.

7. Sociocultural

• Behavior is influenced by society + culture

• Focus: social groups, cultural norms, expectations.

8. Biopsychosocial

- Behavior explained by a combination of:

• Bio (genes/brain), Psych (thoughts), Social (people)

Page 3 — Lesson 1: The Study of the mind

• Psychology comes from latin for "the study of the soul"

• Psychology is very similar to philosophy, but in philosophy it's thinking abstractly.

• If you don't measure, then it doesn't exist

  • needs measurements & experiments to be seen

• 3 important factors a researcher should have

  • Curiosity: why? why does it work? can it be tested?

  • Skepticism: questioning attitude, don't take anything for granted

  • Humility: being able to accept you're incorrect

• Psychologists don't all do the same job because of perspective

• Psychodynamic: conscious, unconscious, subconscious minds.

  • Unconscious: things that disturb us (like a crime)

Conducting Psychological Research

★ Psychologists use the scientific method to test if their ideas about behaviour/mind are true or false.

★ Basic process: theory → hypothesis → sample → collect data → report → peer review → replication

Theory & Hypothesis

• Collection of ideas, observations + principles about topic

• Ex: sleep helps learning & memory

Hypothesis

• A testable claim based on a theory

• Ex: less sleep → remembering less from the previous day

• Falsifiable: can be tested & potentially proven wrong

• Important b/c people naturally have confirmation bias

Operational Definitions & Replications

Operational definition

• explanation of how something is measured in a study

• ex: sleep deprivation = 2h less than normal sleep

• makes possible for others to replicate study

Replication

• Repeating a study to see if similar results occur

• Similar results repeatedly = reliable results

Population & Sampling

★ Population = entire group researchers want to study

★ Sample = smaller group actually studied

Page 4 — Sampling, Peer Review & Lesson 2

Random sample

• everyone in population has equal chance of selection

• reduces sampling bias

Representative sample

• sample reflects the characteristics of the population

• helps researchers generalize results to the population

Convenience sample

• people chosen because they're easy/available

• can cause sampling bias b/c they may not rep. everyone

Peer review

• Study is examined by experts in the field before publication

• Experts check:

  • methods/data

  • possible biases

  • accuracy/validity

• Researchers may need to revise or redo parts

• helps insure published research is accurate/well-supported

Lesson 2

Behavioral

• Psychology seen as an objective science to observe: environment, rewards & punishments

• Founded by Pavlov, Watson, & B.F. Skinner as rejection of psychodynamic

• "We learn every single behaviour"

• Criticism of psychodynamic since it studied the hidden, not truly observable

• Asserts psychology should be objective science, focused on observable behaviour - not unseen mental processes.

• Belief of unlearning through rewards & punishments

  • rewards & punishments come from us, internally as well

  • rejection & absence of love is a punishment behave according to them

Sociocultural (stereotypes, cliches, religion, food, society, school, music, etc)

- We are the product of our society & cultures

Humanistic (free will, personal growth, self-actualisation)

• We need to focus on the human nature (humans are good by nature)

• instead of focusing on your childhood, we move forward & don't revisit

• opposite to Freud. (positive psychology)

• Carl Rodgers

Page 5 — Psychological Perspectives Continued

Cognitive (about mind, not brain)

• the brain is bio, the mind is everything psychology

• emphasises inner thoughts

• Cognitive processes (4)

  • memory

  • thoughts

  • Imagination

  • problem solving

Biological (we are the products of biology)

• behaviour & mental processes are seen as influenced by our nervous system

• helps understand neurological conditions, mental disorders, & effects medication on behaviour.

Biopsychosocial (interconnections between all 3)

- We are the results of our biology, but also our own experience, aswell as sociocultural factors

Evolutionary (Survive, adapt + reproduce)

• Darwin → we became who we are to survive, adapt & reproduce

• Natural selection

  • inheritable trait that helps an organism survive

• We have disorders to survive, adapt & reproduce

How would each perspective explain depression?

Psychodynamic: depression is caused by repressed traumas & uncomfortable experiences we repressed to our unconscious.

Behavioral: this person is depressed because of being constantly punished & role models being portraying depressive behavior.

Sociocultural: because of our social & cultural surroundings, for example, isolation, discrimination, poverty or cultural expectations.

Humanistic: occurs when a person can't reach their potential or live as their authentic self, creating a gap between real & ideal.

Cognitive: Because of maintained negative or distorted patterns.

Bio: influenced by bio factors such as genetics, hormones & neurotransmitters

Evolutionary: may involve responses that once had an adaptive function, such as withdrawing after loss or conserving energy.

BPS: results from an interaction of bio, psycho, & social factors rather than just one single cause.

Page 6 — Types of Research Methods

Experimental vs. Non-experimental

Experimental

• tests cause & effect

• Manipulates IV → measures effect on DV

• control group = no IV, experimental group = gets IV

• Random assignment to groups

• can establish causation

• Artificial setting → some studies unethical/impractical

Non-experimental

• observe variables without manipulation (Naturalistic)

• finds patterns/relationships, NOT causation

Non-Experimental Methods → no cause & effect possible

Case study (adv: lots of info given, dis: not generalizable)

• In-depth study of 1 person/group (very specific)

• useful for one rare/unrepeatable cases

• Ex: Phineas Gage → brain personality & impulse control

• May not generalise; no cause & effect

Naturalistic observation

• observe behaviour in natural settings w/o interfering

• real life behaviour

• Cannot determine cause

Correlational study

• measures relationships between 2 variables

• helps identify patterns/predict

• correlation ≠ causation

Meta-analysis

• statistically combines results of many studies for new conclusion

• gives broader/more reliable conclusion

Types of Data

• Quantitative: numerical/measurable

• Qualitative: descriptions/narratives

Likert scale (strongly disagree → agree) = quantitative, can be assigned numbers

Surveys → data collection method NOT research methodology

• Questionnaire: can be quantitative & qualitative

  • Fast, cheap, large samples

• Answers/questions can be biased

Page 7 — Correlational Research

Correlational research (not experimental b/c there's no cause & effect)

• non-experimental → no variables manipulated

• studies relationships between 2 variables

• shows direction + strength & relationship

• useful when experiments are unethical/impractical

• never cause & effect, instead they look for correlation

Why Correlation ≠ Causation

Directionality problem

• don't know if A → B or B → A

• could also influence eachother

Third-variable problem

• another variable C may cause changes in both A + B

• Ex: ice cream sales ↑ + drownings ↑ → hot weather affects both

Illusionary correlation (many cultural impacts)

• believing a relationship exists when it doesn't

• often caused by biases like confirmation bias

• Ex: Full moon ↔ unusual behaviour

Scatterplots (correlation measured w/ "r") (neg: -1, pos: 1, none: 0)

• X-axis = one variable; Y-axis = other

• each dot = one pair of measurements

• overall pattern shows direction + strength

Positive correlation: variables move together

• one ↑ → other ↑

• ex: hours worked ↑ → income ↑

Negative correlation: variables move opposite

• one ↑ → other ↓

• ex: meals cooked at home ↑ → eating out ↓

Correlation Coefficient (r)

• ranges from -1 to 1

• shows strength + direction

• +1 = perfect positive

• -1 = perfect negative

• 0 = no relationship

• closer to ±1 = stronger

• closer to 0 = weaker

Page 8 — Research Methodology

Population: absolutely everyone in study. Sample: selected group from population

Research Methodology

How psychology design, test, & evaluate research

Hypothesis (testing predictions)

• testable prediction (specific prediction about relationship in variables)

• operational definition (how I'm measuring something in experiment)

• not yet a theory (supported by data from research that was already completed & explains a question, thoughts, or phenomenon)

• must be falsifiable

Participants

• Random sampling

  • each individual in population has an equal chance of participation in the study

• Population

  • every single person relevant to study

Experimental vs Non

• E

  • only way to find cause & effect

• NE

  • no cause & effect

Hawthrown Effect

- When people know they're being monitored so they act different

Methods of data collection

- Peer Review (other experts review the work)

AAQ First question "What is the research methodology?"

Second "What is the IV or DV"

Third "What is operational definition"

When Hypothesis is approved it becomes a theory

Ethical practices

• Consent, right to withdraw, limited deception, no harm, protected from harm & discomfort

• respect privacy, debrief

• research confederates (researchers paying actors

• Animal testing: appropriate, beneficial, caring

Page 9 — Experimental Design

Hypothesis

• testable prediction

• Must be falsifiable = possible to prove wrong

• Variables must be clear + measurable

Variables "does hours of sleep change concentration in class?"

• IV: what researcher changes/manipulates → hours of sleep

• DV: what researcher measures → concentration (depends on h/sleep)

• CV: outside factor that could affect results

Operational Definitions

• exact explanation of how variables are measured/used

• makes study easier to replicate

• ex: IV = one cup of herbal tea/day for 4 weeks, DV: depression score

Sampling

• large sample = more likely to represent population

• Random sampling = everyone in population has equal chance of selection

• Convenience sample may be unrepresentative

• Representative sample reflects population characteristics

• Replication with different samples/settings increases reliability

Experimental Groups

• Experimental group: receives IV

• Control group: doesn't receive IV (receives placebo instead)

• used to compare results

Random Assignment

• participants have have even chance of being placed in either group

• Different from random sampling

Placebo (inactive treatment that resembles real treatment)

• usually given to control groups

• Helps reduce bias

• Placebo Effect: improvement caused by participants expectations

Blinding

• Single-blind = participants don't know their group

• Double-blind = participants + researchers don't know groups

• Helps reduce experimentor bias (researcher expectations can accident influence results)

Data

• Quantitative = numerical

• ex: depression scores

Page 10 — Statistical Analysis: Central Tendency

Peer review + replication

• Peer review: experts check methods, data, conclusions

• Helps find errors/bias

• Replication: repeat study to see if results can be reproduced

Key Reminders for AP

• IV: manipulated

• DV: measured

• Random sampling: choosing participants

• Random assignment: placing participants into groups

Statistical Analysis: Central Tendency

Types of Statistics

• Descriptive stats: summarize/describe collected data

• Inferential stats: use a representative sample to make conclusions about a larger population → helps determine if we can generalise

Measures of Central Tendency

• Mean: average

• Median: middle score

• Mode: most frequent score (more than one possible)

• Used to describe the center of data set

• n = number of participants in sample

Distribution Curves

Normal curve

• Bell-shaped

• most scores near middle

• mean, median & mode around same point

• few extreme high/low scores

Skewed distribution

• outliers pull the mean away from the center

• mean is most affected by extreme scores

• Positive skew = tail points right: high outliers pull mean ↑

• Negative skew = tail points left: low outliers pull mean ↓

Bimodal distribution

- Has 2 modes → 2 peaks

Regression Toward Mean

- Extreme high/low scores tend to move closer to the mean when retested

Page 11 — Variation & Inferential Statistics

Measures of Variation

- show how spread out data is

Range

- highest score - lowest score

Standard deviation (SD or σ)

• shows how spread out scores are around the mean

• High SD = more variety in scores

• Low SD = scores closer together

Normal Curve & SD

• 68% = within 1 SD of mean

• 95% = within 2 SD

• 99.7% = within 3 SD

Percentile Rank

• shows a score's position compared to others

• 86th percentile = scored higher than 86% of scores

Generalizability

• How well results apply to a larger population

• Improved by:

  • large, representative sample

  • random sampling

  • replication

Inferential Statistics

• Statistical significance

  • Shows whether results are unlikely due to chance

  • Measured using p-value

• Effect size

  • Shows how large/important the effect or difference is

  • large effect size = noticeable difference

  • small effect size = small difference

• the smaller the p-value the stronger the statistic (better)

Statistical significance = is the effect likely real?

Effect size = how big is the effect?

Page 12 — Nature, Nurture & Twin Studies

Nature vs Nurture

Nature (Biological)

• Genetics + biology → influences from the inside out

• Can affect personality, intelligence, mental health, temper & language

• Noam Chomsky: humans have an innate ability to acquire language → universal grammar

Nurture (evolutionary)(psychodynamic)(sociocultural)(behaviourism)

• Environment + experiences + learning → influences from outside in

• Includes conditioning, reinforcement, rewards/punishments & associative learning

• John B. Watson: behaviourist saying environment strongly shapes behaviour

★ It's nature & nurture not one or the other. Genes & environment interact to shape development.

Epigenetics (genes can be activated or deactivated temporarily)(slow & many)

- Study of how the environment/experiences can affect gene expression

Rat licking study

• High-licking mothers → offspring became high-licking adult

• Low-licking mothers → offspring became low-licking adult

• When babies were switched they developed behaviour of raising mother

• Maternal care also affected gene expression

• Shows nurture can influence nature

Enriched environment study

• Rats raised in stimulating showed increased long-term potentiation (LTP)

• LTP: strengthening of neural connections involved in learning & memory

• Their offspring also showed signs of LTP → another example of environmental experience interacting with biology.

Plasticity

• the brain changing every second

• the brain arranging itself with new neuron connections

• quickly occurring

Page 13 — Twin Studies

Types of twins

Identical/Monozygotic (MZ)

• 1 egg

• Same DNA

• Same Sex

Fraternal/Dizygotic (DZ)

• 2 eggs

• genetically similar like regular siblings

• can be same or different sexes

Why Twins

★ twins help separate the effects of heredity (nature) & environment (nurture)

• Identical twins raised apart: similarities suggest gene influence

• Researchers use adoption studies, family studies, & DNA studies

Minnesota Twin Studies

• lasted about 35 years & studied twins raised apart

• famous Jim twins had many similarities despite separate growing up

  • Similar marriages/divorces

  • Similar child dog names

  • vacationed in nearly same place

  • both good at math, bad at spelling

• their similarities provided evidence to investigate gene influence.

Heritability (amount of variation among individuals attributable to gene diff)

• a study of about 11,000 twin pairs examined academic achievement

• traits such as motivation, stress response, class preferences, & intelligence showed genetic influence

• About 62% of individual differences in academic test performance were attributed to genetic factors.