AP Psychology Unit 1
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I. The Science of Psychology
A. Core Definition
Psychology: The science that studies how people behave and think.
Behavior: Actions we can see and measure.
Mental Processes: Inner experiences (like thoughts, feelings, dreams, beliefs) that we guess at based on behavior.
B. Philosophical Ideas Behind Psychology
Dualism (Socrates & Plato): Believed the mind and body are totally separate and different. The mind is often seen as not physical.
Monism (Aristotle): Thought the mind and body are part of the same thing. Mental events simply come from physical, body-related processes.
C. The Scientific Way of Learning (Empirical Approach)
Psychology changed from just talking about ideas to being a science by using the empirical method: This is essentially just the SCIENTIFIC METHOD
II. Historical Schools of Thought
Structuralism
Main People: Wilhelm Wundt, Edward Titchener
Goal: To figure out the basic "structure" of the conscious mind by breaking it down into its smallest parts.
Method/What they did: They used introspection (people looked inward to describe their own conscious experiences). Even though it wasn't always accurate, it made psychology an experimental science.
Functionalism
Main People: William James, G. Stanley Hall
Goal: To understand the purpose or function of our mental processes—how they help us adjust, survive, and do well.
Method/What they did: They focused on the "stream of consciousness" (our continuous flow of thoughts). This was inspired by Darwin's theory of evolution; they asked why we think and act in certain ways.
Gestalt
Main People: Max Wertheimer
Goal: To study how the mind naturally sees complete patterns and shapes, rather than just small pieces of sensation.
Method/What they did: They famously said, "The whole is greater than the sum of its parts." They are known for studying visual tricks and the phi phenomenon (seeing movement when there isn't any actual movement).
Psychoanalysis/Psychodynamic
Main People: Sigmund Freud, Carl Jung
Goal: To treat mental problems by finding and solving hidden, unconscious conflicts, which often started in childhood.
Method/What they did: They stressed the importance of the unconscious mind, early life experiences, and inner urges. This approach was criticized for not being scientific enough.
Behaviorism
Main People: John Watson, B.F. Skinner, Ivan Pavlov
Goal: To study only behaviors that can ONLY be directly observed, ignoring the inner workings of the mind.
Method/What they did: They focused on how we learn through connections (classical conditioning) and results (operant conditioning). This was the main way of thinking in psychology for 50 years.
III. Foundational Debates & Frameworks
A. The Three Enduring Issues
Rationality vs. Irrationality: How much control do our conscious, logical thoughts have over our actions and behaviors?
Stability vs. Change: Do our main personality traits stay the same throughout our lives, or can we truly change?
Nature vs. Nurture: How much do our genes (nature) contribute versus our environment, experiences, and culture (nurture) in shaping us?
Genetic Predisposition: This means someone is more likely to develop a certain trait or problem because of their genes. It's not a guarantee, but a higher risk.
B. The Bio-Psycho-Social Model
A complete, combined way of looking at things that says biological, psychological, and social factors all work together to affect a person's thoughts, behaviors, and their chances of getting disorders.
Biological: This includes genes, brain structure/chemistry, nerve function, hormones, diet, and sleep.
Psychological: This covers stress, past trauma, learned ways of thinking, emotions, memories, and beliefs.
Social: This refers to things like social class, culture, family relationships, peer pressure, education, and social support.
IV. The Limits of Intuition: Cognitive Biases (Thinking Traps)
A. Hindsight Bias
What it is: The tendency to believe, after something has happened, that you would have known it would happen all along. It's the "I-knew-it-all-along" feeling.
What it causes: Makes outcomes seem unavoidable and predictable, leading us to be too confident and to underestimate how much chance played a role.
Example: After a stock market crash, many people say the signs were obvious, but very few actually predicted it.
B. Overconfidence Phenomenon
What it is: The tendency to be more confident than you are correct—to think your beliefs and judgments are more accurate than they actually are.
What it causes: Can lead to bad decisions and making light of scientific evidence because you rely too much on "common sense."
Example: A student is 100% sure they got an A on an exam, but actually scores a 70%.
C. Confirmation Bias
What it is: The tendency to look for, understand, prefer, and remember information that supports what you already believe or your existing ideas, while mostly ignoring other possibilities.
What it causes: Keeps wrong ideas going, makes disagreements stronger, and is a big problem for scientific thinking.
How it Shows Up:
Selective Search: Only looking for facts that back up your opinion.
Selective Interpretation: Seeing unclear evidence as supporting your view.
Selective Memory: Remembering things that confirm your beliefs better than things that don't.
Example: Someone who believes in astrology remembers the times a horoscope was "right" but forgets the many times it was wrong.
D. Illusory Correlation
What it is: Seeing a connection between two things when there actually isn't one.
What it causes: Leads to forming stereotypes and superstitious beliefs.
Example: Believing that wearing a certain lucky shirt makes your favorite sports team win.
V. Research Methods
These methods help psychologists study behavior and mental processes.
A. Descriptive Methods (Describe, but Don't Explain Cause)
These methods give us details or snapshots, but they can't tell us why something happens.
Case Study
What: A deep dive into one person or a small group.
Strengths: Gives lots of rich, detailed information; good for studying rare situations.
Weaknesses: What you learn might not apply to everyone else (not generalizable); the researcher's own views can influence the results.
Example: Studying Phineas Gage's brain injury to understand how it changed his personality.
Naturalistic Observation
What: Watching and recording behavior in its normal environment without getting involved.
Strengths: Shows how people (or animals) truly behave in the real world (high external validity).
Weaknesses: No control over what happens; the observer's expectations can affect what they see; it doesn't explain what causes what.
Example: Jane Goodall observing chimpanzees in their natural habitat.
Survey
What: Collecting information about people's attitudes, beliefs, or behaviors, often using questionnaires or interviews.
Strengths: An efficient way to gather a lot of data from many people.
Weaknesses:
Sampling Bias: If the group surveyed doesn't truly represent the larger population, the results will be wrong.
Wording Effect: How questions are asked can change how people answer.
Social Desirability Bias: People might answer in a way that makes them look good or is socially acceptable, rather than giving their true feelings.
B. Correlational Design (Predicts, but Doesn't Prove Cause)
This method looks at how two or more things are related. It helps us predict one from the other, but doesn't show direct cause.
Goal: To find out if there's a relationship between different variables.
Correlation Coefficient (r): A number from -1.00 to +1.00 that shows how strong and in what direction a relationship is.
Direction:
Positive (+): The variables move in the same direction. As one goes up, the other goes up (e.g., more study time usually means higher grades).
Negative (-): The variables move in opposite directions. As one goes up, the other goes down (e.g., more late nights might mean lower alertness).
Strength: The closer r is to ext{+1.00} or ext{-1.00}, the stronger the relationship. If r is 0, there's no relationship.
Crucial Point: Correlation DOES NOT mean one thing causes the other.
Just because two things are related doesn't mean one is the direct cause of the other. A confounding variable (a hidden third factor) might be influencing both.
Example: High ice cream sales and more drownings are correlated. Hot weather (the third variable) causes both, not the ice cream itself.
C. Experimental Design (The Best Way to Prove Cause and Effect)
Experiments are set up to actively change one variable to see if it causes a change in another.
Goal: To clearly show a cause-and-effect relationship.
Key Elements:
Hypothesis: A testable guess or prediction (e.g., "Drinking coffee improves alertness").
Independent Variable (IV): The factor the researcher changes or manipulates (e.g., the amount of coffee given).
Dependent Variable (DV): The outcome that is measured (e.g., alertness level). This needs a clear operational definition (a precise way to measure it).
Experimental Group: The group that receives the special treatment (e.g., gets coffee).
Control Group: The group that does not receive the treatment or gets a placebo. This group is used for comparing results.
Essential Controls for Valid Results:
Random Assignment: Participants are randomly put into either the experimental or control group. This helps make sure the groups are similar beforehand, making it easier to see if the IV caused the difference.
Blinding:
Single-Blind: Participants don't know if they are in the experimental or control group.
Double-Blind: Neither the participants nor the researchers know who is in which group. This prevents the placebo effect (where just expectations influence results) and prevents experimenter bias.
Placebo Effect: When people get results just from their expectations, not from the actual treatment (e.g., feeling better after taking a sugar pill because you think it will work).
D. Meta-analysis (Combining Existing Research)
This method allows researchers to combine and analyze the results from many different studies on the same topic.
What it is: A statistical technique that gathers data and findings from many separate studies to reach a stronger, more reliable conclusion.
Strengths: Gives a more powerful and dependable estimate of an effect; increases statistical power; can help resolve disagreements between findings from individual studies.
Weaknesses: The quality of the meta-analysis depends on the quality of the studies included; publication bias (studies with big results are more likely to be published) can skew the findings.
Example: Combining results from many studies about how well a certain therapy works for depression.
VI. Statistics: Making Sense of Data
A. Descriptive Statistics (Summarizing Data)
These statistics help us summarize and describe the main features of a set of data.
Measures of Central Tendency (Where the Middle Is):
Mean: This is the average. You add all the numbers and divide by how many there are. Be careful, a few very high or very low numbers (outliers) can pull the mean away from the true middle.
Median: This is the middle score when all scores are listed from lowest to highest. Half the scores are above it, and half are below. It's good for data with outliers because they don't affect it much.
Mode: This is the score that appears most often in a dataset.
Measures of Variability (How Spread Out the Data Is):
Range: This is the simplest measure of spread. It's just the difference between the highest and lowest scores. However, extreme scores can easily distort it.
Standard Deviation (SD): This tells you, on average, how much each score differs from the mean.
A low SD means scores are generally close to the mean (clustered).
A high SD means scores are spread out more widely from the mean.
Normal Distribution: This is a common, bell-shaped curve where most scores gather around the average, and fewer scores are found at the very high or very low ends.
B. Inferential Statistics (Making Conclusions)
These statistics help us decide if our research findings are truly meaningful or just happened by chance.
Purpose: To figure out if the results we see in an experiment were genuinely caused by what we changed (the experimental manipulation), or if they just occurred randomly.
Null Hypothesis (H_0): This is the starting idea that there is no real effect or no real difference between groups. It suggests any effect you observe is just due to chance.
p-value: This is a probability. It tells you the chance of getting your observed results (or even stronger ones) if the null hypothesis were actually true (meaning there's no real effect). A small p-value means your results are unlikely to be due to chance.
Statistical Significance: In psychology, a common rule is that if the p-value is less than .05 (p < .05), your results are considered statistically significant.
When p < .05, researchers reject the null hypothesis.
This means they conclude that the results are likely caused by the experimental manipulation (the Independent Variable) and are not just random chance. Think of it like being 95% confident that the results are real and not just luck.
VII. Ethical Principles
A. Human Research (Following APA Rules & IRB Review)
Informed Consent: People must be given enough information about the study so they can freely decide if they want to participate.
Protection from Harm: Researchers must do everything possible to minimize physical and emotional harm. Any risks must be worth the potential benefits of the study.
Confidentiality: Participants' information must be kept private. Their identities should be anonymous whenever possible.
Debriefing: After the study, participants must be told the full purpose of the research and given a way to contact the researcher with questions. Any trickery used must be explained and justified.
B. Animal Research (Following IACUC Rules)
Must be supported by its potential scientific, educational, or practical value.
Must reduce discomfort, illness, and pain as much as possible. Any pain or stress must be very strongly justified.
Reasons for using animals: To learn about different species, study simpler body systems, and conduct research that can't ethically be done with humans.
VIII. Psychological Approach’s
Psychodynamic Approach
Main Idea: Behavior and mental problems come from hidden drives and conflicts in the unconscious mind, often starting in childhood. It's all about the deep, buried stuff.
Main People: Sigmund Freud, Carl Jung, Alfred Adler.
What it Focuses On:
The unconscious mind as a powerful influence.
Early childhood experiences and how they affect us for a long time.
Inner conflicts between basic urges (id), reality (ego), and morals (superego).
Using methods like dream analysis and free association to get into the unconscious.
Keywords to Look Out For: Unconscious, childhood, dreams, repression, Freud, psychoanalysis, inner conflict, id/ego/superego, hidden desires.
How to Remember It: Think of an iceberg. The small part you see above water is the conscious mind, but the huge, hidden part underwater is the unconscious, which secretly guides you.
2. Behavioral Approach
Main Idea: Psychology should only study behavior that can be seen. Behavior is learned from interacting with our surroundings. Forget the mind; just focus on what we can observe and measure.
Main People: Ivan Pavlov, John B. Watson, B.F. Skinner.
What it Focuses On:
Learning through associations (Classical Conditioning) and consequences (Operant Conditioning).
Stimuli (things that cause a reaction) and responses (the reactions). Change the environment, and you change the behavior.
Reinforcement (things that make a behavior happen more) and punishment (things that make a behavior happen less) as ways to shape behavior.
Keywords to Look Out For: Learning, conditioning, reinforcement, punishment, stimulus, response, observable, environment, Skinner, Pavlov, Watson, behavior modification.
How to Remember It: Think of training a dog. The dog doesn't consciously "think" about sitting; it learns that sitting (behavior) earns a treat (reinforcement from the environment).
3. Humanistic Approach
Main Idea: People are naturally good and have the freedom to choose to grow and reach their full potential. This is a positive, hopeful reaction to the negative focus of psychodynamic theory and the strictness of behaviorism.
Main People: Carl Rogers, Abraham Maslow.
What it Focuses On:
Self-actualization—becoming the best version of oneself.
Free will and making conscious choices.
A person's subjective, lived experience (how they personally see and feel things).
The importance of unconditional positive regard (being accepted and valued without judgment).
Keywords to Look Out For: Free will, self-actualization, growth, potential, positivity, Maslow's hierarchy, client-centered therapy, subjective experience, fulfillment.
How to Remember It: Think of a flower seed. It has all the internal potential to grow and bloom beautifully; it just needs the right conditions (sun, water) to do so. The humanistic approach aims to provide that nurturing environment.
4. Cognitive Approach
Main Idea: To understand behavior, we need to study internal mental processes—how we take in, process, store, and recall information. This approach brought the study of the mind back into psychology.
Main People: Jean Piaget, Albert Ellis, Aaron Beck, Noam Chomsky.
What it Focuses On:
Thoughts, perceptions (how we interpret things), memories, beliefs.
How our thinking about something affects our reaction to it.
Schemas (mental frameworks), solving problems, and making decisions.
Keywords to Look Out For: Thoughts, beliefs, memory, perception, information processing, problem-solving, schema, cognitive therapy, "mind as a computer."
How to Remember It: Think of your brain as a computer. The computer takes in data (input), processes it (thinking), and then creates an outcome (output/behavior). The cognitive approach is interested in that "processing software."
5. Biological / Neuroscience Approach
Main Idea: All thoughts, feelings, and behaviors come from a physical, biological source. You are your brain and body.
Main People: James Olds, Roger Sperry, Michael Gazzaniga.
What it Focuses On:
Brain structure and chemistry (neurotransmitters—brain chemicals).
The nervous system and hormones.
Genetics and how evolution influences behavior.
How physical sicknesses and medicines affect the mind.
Keywords to Look Out For: Brain, neuron (nerve cell), neurotransmitter, hormone, genetics, heredity, MRI/PET scans, biology, physiology, amygdala, hippocampus.
How to Remember It: Think of a pharmacist. They explain your mood or behavior based on the chemicals and biological interactions in your body. This approach does the same.
6. Evolutionary Approach
Main Idea: Behaviors and mental processes exist because they helped our ancestors adapt and survive. These helpful traits were then passed down through natural selection, improving their chances of survival and reproduction.
Main Figure: Charles Darwin (inspiration), David Buss.
What it Focuses On:
Natural selection of psychological traits.
How behavior helps our genes survive and be passed on.
Universal human tendencies (e.g., being afraid of snakes, liking sweet/fatty foods).
Keywords to Look Out For: Natural selection, evolution, adaptation, survival, reproduction, fitness, innate (inborn), universal behaviors.
How to Remember It: Think of "Why are we afraid of the dark?" An evolutionary psychologist would say: because our ancestors who were cautious of dark, unknown places were less likely to be attacked by predators and therefore more likely to pass on their "cautious" genes.
7. Sociocultural Approach
Main Idea: Our behavior and thinking are strongly shaped by the rules and expectations of our culture and the people (society) around us.
Main People: Lev Vygotsky, Stanley Milgram, Philip Zimbardo.
What it Focuses On:
Social influence (like fitting in, or obeying authority).
Cultural norms (unspoken rules) and expectations.
How behavior differs across various cultures.
Keywords to Look Out For: Culture, society, norms, social influence, conformity, obedience, roles, ethnicity, cross-cultural.
How to Remember It: Think of peer pressure. Why do you sometimes act differently around your friends than your family? Because your immediate social group influences you. This approach studies that idea on a broader scale.
8. Biopsychosocial Approach
Main Idea: This is a complete and combined way of thinking that says biological, psychological, and social factors are all connected and must be considered together to understand health and behavior. This is not a single "approach" but rather a model that combines aspects from others.
What it Focuses On: The interaction between:
BIOlogical (genes, brain chemistry)
PSYCHOlogical (stress, past hurts, learned behaviors)
SOCIAL (family, culture, social status)
Keywords to Look Out For: Holistic, interaction, combination, multifaceted, comprehensive.
How to Remember It: Think of a three-legged stool. If one leg (biological, psychological, or social) is broken, the whole stool falls over. All three are needed for a full understanding of a person.
9. Eclectic Approach
Definition: Most modern therapists don't stick to just one approach. Instead, they use an eclectic approach, meaning they use and mix techniques and ideas from several different schools of thought to best suit each client's specific needs.
Analogy: Think of a chef. A strict chef might only use French cooking methods (one approach). An eclectic chef is like a fusion chef—they take the best techniques from Italian, Thai, and French cooking (multiple approaches) to create the perfect dish for each situation.
Example: A therapist might use behavioral methods (like exposure therapy) for someone's anxiety, but also use humanistic methods (like offering