AP Psychology Important Terms

Behavior

everything we do that can be directly observed

Behavioral Approach

an approach to psychology focusing on the scientific study of observable behavioral responses and their environmental determinants

Biological Approach

an approach to psychology focusing on the body, especially the brain and nervous system

Cognitive Approach

an approach to psychology focusing on the mental processes involved in knowing: how we direct our attention, perceive, remember, think, and solve problems

Evolutionary Approach

an approach to psychology focusing on evolutionary ideas such as adaptation, reproduction, and natural selection as the basis for explaining specific human behaviors

Functionalism

James's approach to mental processes, emphasizing the functions and purposes of the mind and behavior in the individual's adaptation to the environment

Humanistic Approach

an approach to psychology focusing on a person's positive qualities, the capacity for positive growth, and the freedom to choose one's destiny

Mental Processes

the thoughts, feelings, and motives that each of us experiences privately but that cannot be observed directly

Natural Selection

Darwin's principle of an evolutionary process in which organisms that are better adapted to their environment will survive and produce more offspring

Psychodynamic Approach

an approach to psychology focusing on unconscious thought, the conflict between biological drives (such as the drive for sex) and society's demands, and early childhood family experiences

Sociocultural Approach

an approach to psychology focusing on the ways in which social and cultural environments influence behavior

Structuralism

Wundt's approach to discovering the basic elements, or structures, of mental processes; so-called because of its focus on identifying the structures of the human mind

Case Study or Case History

an in-depth look at a single individual

Control Group

the participants in an experiment who are as much like the experimental group as possible and who are treated in every way like the experimental group except for a manipulated factor, the independent variable

Correlational Research

research that examines the relationship between variables with the purpose of determining whether and how two variables change together

Demand Characteristics

any aspect of a study that communicates to the participants how the experimenter wants them to behave

Dependent Variable

the outcome; the variable that may change in an experiment in response to changes in the independent variable

Descriptive Research

research that determines the basic dimensions of a phenomenon—defining what it is, how often it occurs, and so on

Descriptive Statistics

mathematical procedures that are used to describe and summarize sets of data in a meaningful way

Double-Blind Experiment

an experimental design in which neither the experimenter nor the participants are aware of which participants are in the experimental group and which are in the control group until the results are calculated

Empirical Method

gaining knowledge through the observation of events, the collection of data, and logical reasoning

Experiment

a carefully regulated procedure in which the researcher manipulates one or more variables that is believed to influence some other variable

Experimental Group

the participants in an experiment who receive the drug or other treatment under study; those who are exposed to the change that the independent variable represents

Experimenter Bias

the influence of the experimenter's expectations on the outcome of the research

External Validity

the degree to which an experimental design actually reflects the real-world issues it is supposed to address

Hypothesis

an educated guess that derives logically from a theory; a prediction that can be tested

Independent Variable

a manipulated experimental factor; the variable that the experimenter changes to see what its effects are

Inferential Statistics

mathematical methods that are used to indicate whether the data sufficiently support a research hypothesis

Internal Validity

the degree to which changes in the dependent variable are due to the manipulation of the independent variable

Mean

a measure of central tendency that is the average for a sample

Median

a measure of central tendency that is the middle score in a sample

Mode

a measure of central tendency that is the most common score in a sample

Naturalistic Observation

the observation of behavior in a real-world setting

Operational Definition

a definition that provides an objective description of how a variable is going to be measured and observed in a particular study

Placebo

in a drug study, a harmless substance that has no physiological effect, given to participants in a control group so that they are treated identically to the experimental group except for the active agent

Placebo Effect

a phenomenon in which the expectation of the participants, rather than actual treatment, produces an outcome

Population

the entire group about which the investigator wants to draw conclusions

Random Assignment

the assignment of participants to experimental groups by chance, to reduce the likelihood that a study's results will be due to preexisting differences between groups

Random Sample

a sample that gives every member of the population an equal chance of being selected

Range

a measure of dispersion that is the difference between the highest and lowest scores

Research Participant Bias

in an experiment, the influence of participants' expectations, and of their thoughts on how they should behave, on their behavior

Sample

the subset of the population chosen by the investigator for study

Standard Deviation

a measure of dispersion that indicates how much the scores in a sample differ from the mean in the sample

Theory

a broad idea or set of closely related ideas that attempts to explain observations and to make predictions about future observations

Third Variable Problem

the circumstance in which a variable that has not been measured accounts for the relationship between two other variables. third variables are also known as confounds

Variable

anything that can change.

Action Potential

the brief wave of positive electrical charge that sweeps down the axon

Adrenal Glands

glands at the top of each kidney that are responsible for regulating mood, energy level, and the ability to cope with stress

Afferent (Sensory) Nerves

nerves that carry information about the external environment to the brain and spinal cord via sensory receptors

All-or-Nothing Principle

the principle that once the electrical impulse reaches a certain level of intensity (its threshold), it fires and moves all the way down the axon without losing any intensity

Amygdala

an almond-shaped structure within the base of the temporal lobe that is involved in the discrimination of objects that are necessary for the organism's survival, such as appropriate food, mates, and social rivals. there is one amygdala in each hemisphere of the brain

Association Cortex or Association Area

the region of the cerebral cortex that is the site of the highest intellectual functions, such as thinking and problem solving

Autonomic Nervous System

the body system that takes messages to and from the body's internal organs, monitoring such processes as breathing, heart rate, and digestion

Axon

the part of the neuron that carries information away from the cell body toward other cells

Brain Stem

the stemlike brain area that includes much of the hindbrain (excluding the cerebellum) and the midbrain; it connects with the spinal cord at its lower end and then extends upward to encase the reticular formation in the midbrain

Cell Body (Soma)

the part of the neuron that contains the nucleus, which directs the manufacture of substances that the neuron needs for growth and maintenance

Central Nervous System (CNS)

the brain and spinal cord

Cerebral Cortex

part of the forebrain, the outer layer of the brain, responsible for the most complex mental functions, such as thinking and planning

Chromosomes

in the human cell, threadlike structures that come in 23 pairs, one member of each pair originating from each parent, and that contain the remarkable substance DNA

Corpus Callosum

the large bundle of axons that connects the brain's two hemispheres, responsible for relaying information between the two sides

Dendrites

treelike fibers projecting from a neuron, which receive information and orient it toward the neuron's cell body

Deoxyribonucleic Acid (DNA)

a complex molecule in the cell's chromosomes that carries genetic information

Dominant-Recessive Genes Principle

the principle that, if one gene of a pair is dominant and one is recessive, the dominant gene overrides the recessive gene. A recessive gene exerts its influence only if both genes of a pair are recessive

Efferent (Motor) Nerves

nerves that carry information out of the brain and spinal cord to other areas of the body

Endocrine System

the body system consisting of a set of glands that regulate the activities of certain organs by releasing their chemical products into the bloodstream

Frontal Lobe

the portions of the cerebral cortex behind the forehead that are involved in personality, intelligence, and the control of voluntary muscles

Genes

the units of hereditary information, consisting of short segments of chromosomes composed of DNA

Genotype

an individual's genetic heritage; one's actual genetic material

Glands

organs or tissues in the body that create chemicals that control many bodily functions

Glial Cells (Glia)

the second of two types of cells in the nervous system; glial cells provide support, nutritional benefits, and other functions and keep neurons running smoothly

Hippocampus

the structure in the limbic system that has a special role in the storage of memories

Hormones

chemical messengers that are produced by the endocrine glands and carried by the bloodstream to all parts of the body

Hypothalamus

a small forebrain structure, located just below the thalamus, that monitors three pleasurable activities—eating, drinking, and sex—as well as emotion, stress, and reward

Limbic System

a loosely connected network of structures under the cerebral cortex, important in both memory and emotion. Its two principal structures are the amygdala and the hippocampus

Motor Cortex

a region in the cerebral cortex that processes information about voluntary movement, located just behind the frontal lobes

Myelin Sheath

a layer of fat cells that encases and insulates most axons

Nervous System

the body's electrochemical communication circuitry

Neural Networks

networks of nerve cells that integrate sensory input and motor output

Neurons

one of two types of cells in the nervous system; neurons are the type of nerve cell that handles the information-processing function

Neurotransmitters

chemical substances that are stored in very tiny sacs within the terminal buttons and involved in transmitting information across a synaptic gap to the next neuron

Occipital Lobe

structures located at the back of the head that respond to visual stimuli

Parasympathetic Nervous System

the part of the autonomic nervous system that calms the body

Parietal Lobe

structures at the top and toward the rear of the head that are involved in registering spatial location, attention, and motor control

Peripheral Nervous System (PNS)

the network of nerves that connects the brain and spinal cord to other parts of the body

Phenotype

an individual's observable characteristics

Pituitary Gland

a pea-sized gland just beneath the hypothalamus that controls growth and regulates other glands

Plasticity

the brain's special physical capacity for change

Resting Potential

the stable, negative charge of an inactive neuron

Reticular Formation

a system in the midbrain comprising a diffuse collection of neurons involved in stereotyped patterns of behavior such as walking, sleeping, and turning to attend to a sudden noise

Somatic Nervous System

the body system consisting of the sensory nerves, whose function is to convey information from the skin and muscles to the CNS about conditions such as pain and temperature, and the motor nerves, whose function is to tell muscles what to do

Somatosensory Cortex

a region in the cerebral cortex that processes information about body sensations, located at the front of the parietal lobes

Sympathetic Nervous System

the part of the autonomic nervous system that arouses the body to mobilize it for action and thus is involved in the experience of stress

Synapses

tiny spaces between neurons; the gaps between neurons are referred to as synaptic gaps

Temporal Lobes

structures in the cerebral cortex that are located just above the ears and are involved in hearing, language processing, and memory

Thalamus

the forebrain structure that sits at the top of the brain stem in the brain's central core and serves as an important relay station

Broca's Area

controls language expression - an area of the frontal lobe, usually in the left hemisphere, that directs the muscle movements involved in speech

Wernicke's Area

controls language reception - a brain area involved in language comprehension and expression; usually in the left temporal lobe

Absolute Threshold

the minimum amount of stimulus energy that a person can detect

Apparent Movement

the perception that a stationary object is moving

Attention

the process of focusing awareness on a narrow aspect of the environment