AP Psychology Unit 1 Notes: Scientific Foundations

Get ready for the AP Psychology exam with our free AP Psychology study notes. We've compiled concise unit summaries and key terms and people to jumpstart your AP test prep. These AP Psychology study notes should be used to supplement what you’re learning in your AP Psych class. More study strategies and expert tips can be found in our latest AP Psychology Test Prep Book.

[ READ NEXT: AP Psychology Unit 2 Notes: Biological Bases of Behavior ]

AP Psychology: Unit 1 Summary

This first unit focuses on the historical origins of the science of psychology, current psychological perspectives, and the research methods psychologists use to gather data about human thinking and behavior. 

History of Psychology

One way to think about the history of psychology is to organize the various theorists and theories into “waves,” or schools of thought. Each wave is a way of thinking about human thought and behavior that dominated the field for a certain period of time until a new way of looking at psychology started to dominate the field. There are five ways: Introspection, Gestalt Psychology, Psychoanalysis, Behaviorism, and Multiple Perspectives.

Different contemporary psychologists look at human thought and behavior from different perspectives. Contemporary perspectives can be placed into eight broad categories: Humanistic, Psychoanalytic, Biopsychology (or Neuroscience), Evolutionary (or Darwinian), Behavioral, Cognitive, Social-Cultural (or Sociocultural), and Biopsychosocial.

Research and Methodology

Psychology is a science, and it is therefore based on research. Though people are often guided effectively by their common intuition, sometimes it leads us astray. People have the tendency upon hearing about research findings (and many other things) to think that they knew it all along; this tendency is called hindsight bias. After an event occurs, it is relatively easy to explain why it happened. The goal of scientific research, however, is to predict what will happen in advance.

An understanding of research methods is fundamental to psychology. Because of that, you are more likely to see a free-response (or essay) question on this topic than on any other. Sometimes psychologists conduct research in order to solve practical problems. For instance, psychologists might compare two different methods of teaching children to read in order to determine which method is better or they could design and test the efficacy of a program to help people quit smoking. This type of research is known as applied research because it has clear, practical applications. Other psychologists conduct basic research. Basic research explores questions that are of interest to psychologists but are not intended to have immediate, real-world applications. Examples of basic research would include studying how people form their attitudes about others and how people in different cultures define intelligence.

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AP Psychology: Unit 1 Key Terms & People

Below, we describe some of the Unit 1 key terms and people you should review ahead of the AP Psychology exam.

• Introspection: The examination of one’s own mental and emotional processes.
  
• Structuralism: The idea that the mind operates by combining subjective emotions and objective sensations, a theory developed by Wilhelm Wundt.
  
• Gestalt Psychology: Gestalt psychology tried to examine a person’s total experience because the way we experience the world is more than just an accumulation of various perceptual experiences. Gestalt theorists demonstrated that the whole experience is often more than just the sum of the parts of the experience.
  
• Sigmund Freud: Freud revolutionized psychology with his psychoanalytic theory. While treating patients for various psychosomatic complaints, Freud believed he discovered the unconscious mind—a part of our mind over which we do not have conscious control that determines, in part, how we think and behave
  
• Repression: Freud believed that this hidden part of ourselves builds up over the years through repression – the pushing down into the unconscious events and feelings that cause so much anxiety and tension that our conscious mind cannot deal with them.
  
• Behaviorism: Behaviorists maintain that psychologists should look at only behavior and causes of behavior – stimuli (environmental events) and responses (physical reactions) – and not concern themselves with describing elements of consciousness.
  
• B.F. Skinner: Another behaviorist, B. F. Skinner expanded the basic ideas of behaviorism to include the idea of reinforcement – environmental stimuli that either encourage or discourage certain responses.
  
• Eclectic: Currently, there is no one way of thinking about human thought and behavior that all or even most psychologists share. Many psychologists describe themselves as eclectic – drawing from multiple perspectives.
  
• Humanist Perspective: Humanists stressed individual choice and free will. They believe that we choose most of our behaviors and these choices are guided by physiological, emotional, or spiritual needs.
  
• Psychoanalytic Perspective: Psychologists using this perspective believe that the unconscious mind – a part of our mind that we do not have conscious control over or access to – controls much of our thought and action. Psychoanalysts would look for impulses or memories pushed into the unconscious mind through repression. This perspective thinks that to understand human thought and behavior, we must examine our unconscious mind through dream analysis, word association, and other psychoanalytic therapy techniques.
  
• Biopsychology (or Neuroscience) Perspective: Biopsychologists explain human thought and behavior strictly in terms of biological processes. Human cognition and reactions might be caused by effects of our genes, hormones, and neurotransmitters in the brain or by a combination of all three.
  
• Evolutionary (or Darwinian) Perspective: Evolutionary psychologists (also sometimes called sociobiologists) examine human thoughts and actions in terms of natural selection. Some psychological traits might be advantageous for survival, and these traits would be passed down from the parents to the next generation.
  
• Behavioral Perspective: Behaviorists explain human thought and behavior in terms of conditioning. Behaviorists look strictly at observable behaviors and human and animal responses to different kinds of stimuli.
  
• Cognitive Perspective: Cognitive psychologists examine human thought and behavior in terms of how we interpret, process, and remember environmental events. In this perspective, the rules that we use to view the world are important to understanding why we think and behave the way we do.
  
• Social-Cultural (or Sociocultural) Perspective: Social-cultural psychologists look at how our thoughts and behaviors vary between cultures. They emphasize the influence culture has on the way we think and act. A social-cultural psychologist might explain a person’s tendency to be extroverted by examining his or her culture’s rules about social interaction.
  
• Biopsychosocial Perspective: This modern perspective acknowledges that human thinking and behavior results from combinations of biological (“bio”), psychological (“psycho”), and social (“social”) factors. Psychologists who emphasize the biopsychosocial perspective view other perspectives as too focused on specific influences on thinking and behavior (sometimes called “being reductionistic”).
  
• Hindsight bias: People have the tendency upon hearing about research findings (and many other things) to think that they knew it all along; this tendency is called hindsight bias.
  
• Hypothesis: A hypothesis expresses a relationship between two variables. Variables, by definition, are things that can vary among the participants in the research.
  
• Theory: A theory aims to explain some phenomenon and allows researchers to generate testable hypotheses with the hope of collecting data that support the theory.
  
• Valid: Good research is both valid and reliable. Research is valid when it measures what the researcher set out to measure; it is accurate.
  
• Reliable: Research is reliable when it can be replicated; it is consistent. If the researcher conducted the same research in the same way, the researcher would get similar results.
  
• Sampling: The individuals on which the research will be conducted are called participants (or subjects), and the process by which participants are selected is called sampling.
  
• Experiment: Psychologists’ preferred method of research is the experiment because only through a carefully controlled experiment can one show a causal relationship. An experiment allows the researcher to manipulate the independent variable and control for confounding variables.
  
• Correlation: A correlation expresses a relationship between two variables without ascribing cause. Correlations can be either positive or negative. A positive correlation between two things means that the presence of one thing predicts the presence of the other. A negative correlation means that the presence of one thing predicts the absence of the other.
  
• Naturalistic observation: Sometimes researchers opt to observe their participants in their natural habitats without interacting with them at all. Such unobtrusive observation is called naturalistic observation. The goal of naturalistic observation is to get a realistic and rich picture of the participants’ behavior. To that end, control is sacrificed.
  
• Case study method: The case study method is used to get a full, detailed picture of one participant or a small group of participants. While case studies allow researchers to get the richest possible picture of what they are studying, the focus on a single individual or small group means that the findings cannot be generalized to a larger population.
  
• Descriptive statistics: Descriptive statistics, as the name suggests, simply describe a set of data. For instance, if you were interested in researching what kinds of pets your schoolmates have, you might summarize that data by creating a frequency distribution that would tell you how many students had dogs, cats, zebras, and so on.
  
• Correlation: A correlation measures the relationship between two variables. Correlations can be either positive or negative.
  
• Inferential statistics: Whereas descriptive statistics provide a way to summarize information about the sample studied, the purpose of inferential statistics is to determine whether or not findings can be applied to the larger population from which the sample was selected.