AP Psychology

Psychological Perspectives

Eight broad categories contemporary psychologists use to look at human thought and behavior.

Humanist Perspective

Emphasizes individual choice and free will, guided by physiological, emotional, or spiritual needs; associated with Abraham Maslow and Carl Rogers.

Psychodynamic Perspective

Believes the unconscious mind, including repressed impulses and memories, controls much of our thought and action.

Biopsychology (Neuroscience) Perspective

Explains human cognition and reactions strictly through biological processes like genes, hormones, and neurotransmitters.

Evolutionary (Darwinian) Perspective

Examines human thoughts and actions through natural selection and survival advantages passed down through generations; based on Charles Darwin's theories.

Behavioral Perspective

Explains human thought and behavior purely in terms of conditioning, focusing strictly on observable behaviors, rewards, and punishments.

Cognitive Perspective

Analyzes human thought and behavior based on how individuals interpret, process, and remember environmental events; associated with Jean Piaget.

Social-Cultural (Sociocultural) Perspective

Emphasizes how cultural norms and rules influence the way people think and act.

Biopsychosocial Perspective

A modern approach that combines biological, psychological, and social factors to explain behavior, avoiding reductionism.

Eclectic Point of View

A viewpoint claiming that no single perspective has all the answers to the variety of human thought and behavior.

Humanism vs. Behaviorism (Exam Trap)

Behaviorists are deterministic and believe past conditioning causes behavior, while humanists contrast this by stressing individual choice and free will.

Hindsight Bias

The tendency for people to believe they knew the outcome all along after an event has already occurred.

Confirmation Bias

The tendency to pay more attention to information that supports our preexisting ideas.

Overconfidence

The tendency to be overly confident about the things we believe.

Applied Research

Research conducted to solve clear, practical problems.

Basic Research

Research that explores questions of interest to psychologists but is not intended to have immediate, real-world applications.

Hypothesis

A falsifiable statement expressing a relationship between two variables.

Independent Variable

The variable that researchers manipulate in an experiment to test its effects.

Dependent Variable

The variable that is measured in an experiment, which depends on the independent variable.

Operational Definitions

Detailed explanations of exactly how variables will be measured, which is essential for research validity and reliability.

Validity

When research accurately measures what the researcher set out to measure.

Reliability

When research is consistent and can be replicated with similar results.

Random Sampling

A selection process where every member of a population has an equal chance of being chosen to participate, which increases the likelihood of a representative sample.

Convenience Sampling

Collecting data from a group of people who are easily accessible to you, which does not result in a representative sample.

Stratified Sampling

A process ensuring that the sample represents the population on specific criteria, such as race, in the same proportions they appear in the overall population.

Experimental Method

The preferred research method in psychology because it is the only way to establish a cause and effect relationship.

Confounding Variables

Any difference between the experimental and control conditions, other than the independent variable, that might skew the dependent variable.

Random Assignment

Giving every participant an equal chance of being placed into either the experimental or control group to limit participant-relevant confounding variables.

Experimenter Bias

The unconscious tendency for researchers to treat members of the experimental and control groups differently to increase the chance of confirming their hypothesis.

Double-Blind Study

A study design where neither the participants nor the researcher know the group assignments, which eliminates experimenter bias.

Single-Blind Study

A study where only the participants do not know to which group they have been assigned, minimizing demand characteristics and response bias.

Hawthorne Effect

The finding that merely selecting a group of people on whom to experiment will affect the performance of that group, regardless of what treatment is actually done to them.

Placebo Effect

The psychological effect of people thinking they took a drug when they actually received an inert substance.

Positive Correlation

A relationship indicating that the presence of one thing predicts the presence of another.

Negative Correlation

A relationship indicating that the presence of one thing predicts the absence of the other.

Directionality Problem

The inability to tell which variable came first in a correlational study.

Naturalistic Observation

Unobtrusively observing participants in their natural habitats to get a rich, realistic picture of behavior, though it sacrifices experimental control.

Case Study

A qualitative method offering a deeply detailed picture of a single participant or a small group, though findings cannot be generalized to a larger population.

Descriptive Statistics

Statistics that simply describe a set of data, such as frequency distributions or graphs.

Central Tendency

Statistical measures that attempt to mark the center of a distribution, such as mean, median, and mode.

Mean

The average of all the scores in a distribution; highly affected by outliers.

Median

The central score in a distribution when ordered from lowest to highest; often used when outliers are present.

Mode

The score that appears most frequently in a distribution.

Bimodal

A distribution where two scores appear equally frequently and more often than any other scores.

Positively Skewed

A distribution skewed by extremely high outliers, causing the mean to be higher than the median.

Negatively Skewed

A distribution skewed by extremely low outliers, causing the mean to be lower than the median.

Measures of Variability

Statistics that depict the diversity or spread of a distribution, such as range, variance, and standard deviation.

Range

The distance between the highest and lowest scores in a distribution.

Variance

A measure related to the average distance of any score in the distribution from the mean.

Standard Deviation

The square root of the variance; measures the average distance of scores from the mean.

z-score

Measures the distance of a score from the mean in units of standard deviation.

Normal Curve

A theoretical bell-shaped curve where roughly 68% of scores fall within 1 standard deviation, 95% within 2, and 99% within 3.

Percentiles

Indicate the distance of a score from zero; someone in the 90th percentile scored better than 90 percent of participants.

Correlation

A measure of the relationship between two variables; does not establish cause and effect.

Correlation Coefficient

A statistic indicating the strength of a correlation, ranging from -1 (perfect negative) to +1 (perfect positive), with 0 denoting no correlation.

Scatterplot

A graph of pairs of values on the x and y axes used to visualize correlations.

Inferential Statistics

Statistics used to determine whether findings from a sample can be generalized to the larger population.

Sampling Error

The extent to which a sample differs from the population from which it was selected.

p-value

The probability that the difference between groups in an experiment is simply due to chance.

Statistically Significant

A result with a p-value of 0.05 or less, indicating a 5 percent or less probability that the results occurred by chance.

Effect Size

A measure that quantifies the practical significance or magnitude of a research finding.

Replication Crisis

A recent trend in science where many efforts to replicate past study results have failed, highlighting the need for caution.

Meta-analysis

Research that combines the results of many different studies on the same topic to determine an overall average effect.

Peer Review

A pre-publication process where experts in the field evaluate a study to ensure high quality and valid methodology.

Institutional Review Board (IRB)

A board that reviews all proposed academic research for ethical violations and procedural errors.

Animal Research Ethics

APA guidelines requiring a clear scientific purpose, humane care and housing, legal acquisition, and minimal suffering for animal subjects.

No Coercion

The ethical guideline requiring that all human participation in research be completely voluntary.

Informed Consent

The ethical guideline stating participants must know they are involved in research and agree to it; any deception cannot invalidate this consent.

Informed Assent

The agreement of minors to participate in research, usually required alongside parental consent.

Confidentiality

The ethical protection of participants' privacy, ensuring their identities and actions are not publicly revealed by researchers.

Protection from Harm (Risk)

The ethical standard that participants cannot be placed at significant, long-term mental or physical risk.

Debriefing

The ethical requirement to tell participants the true purpose of the study after it concludes, which is especially critical if deception was used.

Genetic Predisposition

The increased chance of developing a specific trait or condition due to our genetic code.

Neurons

Individual nerve cells that make up our entire nervous system.

Dendrites

Rootlike parts of a neuron that stretch out from the cell body to make synaptic connections with other neurons.

Cell Body (Soma)

Contains the nucleus and other parts of the neuron needed to sustain its life.

Axon

Wirelike structure ending in the terminal buttons that extends from the cell body of a neuron.

Myelin Sheath

A fatty covering around the axon of some neurons that speeds neural impulses.

Terminal Buttons

The branched end of the axon that contains neurotransmitters.

Neurotransmitters

Chemicals contained in terminal buttons that enable neurons to communicate by fitting into receptor sites on dendrites.

Synapse

The space between the terminal buttons of one neuron and the dendrites of the next neuron.

Resting Potential

The resting state of a neuron when it has an overall slightly negative charge.

Threshold

The level of neurotransmitters required to be received by a neuron to make its cell membrane permeable and trigger firing.

Action Potential

The electric message firing that spreads down the length of a neuron.

All-or-None Principle

The fact that a neuron either fires completely or does not fire at all; the impulse is the same every time.

Depolarization

The process of neural firing where positive ions rush into the cell, changing the overall charge from negative to positive.

Excitatory Neurotransmitters

Chemicals that excite the next cell into firing.

Inhibitory Neurotransmitters

Chemicals that inhibit the next cell from firing.

Dopamine

Neurotransmitter involved in motor movement and alertness; lack is associated with Parkinson's, excess with schizophrenia.

Serotonin

Neurotransmitter involved in mood control; lack is associated with clinical depression.

Norepinephrine

Neurotransmitter involved in alertness and arousal; lack is associated with depression.

Glutamate

Excitatory neurotransmitter involved in memory; excess can trigger migraines and seizures.

GABA

Important inhibitory neurotransmitter; issues can cause seizures and sleep problems.

Endorphins

Neurotransmitters involved in pain control and addictions.

Substance P

Neurotransmitter associated with pain perception.

Acetylcholine

Neurotransmitter involved in motor movement; lack is associated with Alzheimer's disease and Myasthenia gravis.

Sensory (Afferent) Neurons

Neurons that take information from the senses to the brain.

Interneurons

Neurons that take messages once they reach the brain or spinal cord and send them elsewhere in the brain or to motor neurons.

Motor (Efferent) Neurons

Neurons that take information from the brain to the rest of the body.

Central Nervous System (CNS)

Consists of our brain and spinal cord; all the nerves housed within bone.