Units 1.1-3

critical thinking

a way of considering things that does not blindly accept arguments and conclusions. Rather, it examines assumptions, appraises the source, discerns hidden biases, evaluates evidence, and assesses conclusions.

empiricism

the idea that knowledge comes from experience, and that observation and experimentation enable scientific knowledge

structuralism

an early school of thought promoted by Wundt and Titchener; used introspection to reveal the parts of the human mind.

introspection

the process of looking inward in an attempt to directly observe one's own psychological processes.

functionalism

an early school of thought promoted by James and influenced by Darwin; explored how mental and behavioral processes work—how they enable the organism to adapt, survive, and flourish.

behaviorism

the view that psychology (1) should be an objective science that (2) studies behavior without reference to mental processes. Most psychologists today agree with (1) but not with (2).

humanistic psychology

a historically significant perspective that emphasized human growth potential, free will, and self-actualization.

cognitive psychology

the study of mental processes, such as occur when we perceive, learn, remember, think, communicate, and solve problems.

cognitive neuroscience

the interdisciplinary study of the brain activity such as perception, thinking, memory, and language.

psychology

the science of behavior and mental processes.

nature-nurture issue

the longstanding controversy over the relative contributions that genes and experience make to the development of psychological traits and behaviors.

natural selection

the principle that inherited traits that better enable an organism to survive and reproduce in a particular environment will (in competition with other trait variations) most likely be passed on to succeeding generations.

evolutionary psychology

the study of the evolution of behavior and the mind, using principles of natural selection.

behavior genetics

the study of the relative power and limits of genetic and environmental influences on behavior.

culture

the enduring behaviors, ideas, attitudes, values, and traditions shared by a group of people and transmitted from one generation to the next.

positive psychology

the scientific study of human flourishing, with the goals of discovering and promoting strengths and virtues that help individuals and communities to thrive.

biopsychosocial approach

an integrated approach that incorporates biological, psychological, and social-cultural viewpoints.

behavioral psychology (behaviorism)

the scientific study of observable behavior, and its explanation by principles of learning.

biological psychology

the scientific study of the links between the physical (genetic, neural, hormonal) and psychological processes.

psychodynamic psychology

a branch of psychology that studies how unconscious drives and conflicts influence behavior and uses that information to treat people with psychological disorders.

social-cultural psychology

the study of how situations and cultures affect our behavior and thinking.

testing effect

enhanced memory after retrieving, rather than simply rereading, information.

SQ3R

a study method incorporating five steps: Survey, Question, Read, Retrieve, Review.

psychometrics

the scientific study of the measurement of human abilities, attitudes, and traits.

basic research

pure science that aims to increase the scientific knowledge base.

developmental psychology

a branch of psychology that studies physical, cognitive, and social change throughout the life span.

educational psychology

the study of how psychological processes affect and can enhance teaching and learning.

personality psychology

the study of individuals' characteristic patterns of thinking, feeling, and acting.

social psychology

the scientific study of how we think about, influence, and relate to one another.

applied research

scientific study that aims to solve practical problems.

industrial-organizational (I/O) psychology

the application of psychological concepts and methods to optimizing human behavior in workplaces.

human factors psychology

a field of psychology allied with I/O psychology that explores how people and machines interact and how machines and physical environments can be made safe and easy to use.

counseling psychology

a branch of psychology that assists people with problems in living (often related to school, work, or marriage) and in achieving greater well-being.

clinical psychology

a branch of psychology that studies, assesses, and treats people with psychological disorders.

psychiatry

a branch of medicine dealing with psychological disorders; practiced by physicians who are licensed to provide medical (for example, drug) treatments as well as psychological therapy.

community psychology

a branch of psychology that studies how people interact with their social environments and how social institutions affect individuals and groups.

hindsight bias

the tendency to believe, after learning an outcome, that one would have foreseen it. (Also known as the I-knew-it-all-along phenomenon.)

theory

an explanation using an integrated set of principles that organizes observations and predicts behaviors or events.

hypothesis

a testable prediction, often implied by a theory.

operational definition

a carefully worded statement of the exact procedures used in a research study.

replication

repeating the essence of a research study, usually with different participants in different situations, to see whether the basic finding can be reproduced.

case study

a descriptive technique in which one individual or group is studied in depth in the hope of revealing universal principles.

naturalistic observation

a descriptive technique of observing and recording behavior in normally occurring situations without trying to manipulate or control the situation.

survey

a descriptive technique for obtaining the self-reported attitudes or behaviors of a particular group, usually by questioning a representative, random sample of the group.

sampling bias

a flawed process when selecting people from the population that produces an unrepresentative sample.

population

all those in a group being studied, from which samples may be drawn.

random sample

a sample that fairly represents a population because each member has an equal chance of inclusion.

correlation

a measure of the extent to which two factors vary together, and thus of how well either factor predicts the other.

correlation coefficient

a statistical index of the relationship between two things (from −1.00 to +1.00).

variable

anything that can change and is feasible and ethical to measure.

scatterplot

a graphed cluster of dots, each of which represents the values of two variables. The slope of the points suggests the direction of the relationship between the two variables. Can show extent of correlation.

illusory correlation

perceiving a relationship where none exists, or perceiving a stronger-than-actual relationship.

regression toward the mean

the tendency for extreme or unusual scores or events to fall back toward the average.

experiment

a research method in which an investigator manipulates one or more factors (independent variables) to observe the effect on some behavior or mental process (the dependent variable). By random assignment of participants, researcher aims to control other relevant factors.

experimental group

in an experiment, the group exposed to the treatment, that is, to one version of the independent variable.

control group

in an experiment, the group not exposed to the treatment; serves as a comparison for evaluating the effect of the treatment.

random assignment

putting participants in experimental and control groups by chance, thus minimizing preexisting differences between the different groups.

double-blind procedure

an experimental procedure in which both the research participants and the research staff are ignorant about whether the research participants have received the treatment or a placebo.

placebo effect

experimental results caused by expectations alone; any effect on behavior caused by the administration of an inert substance or condition, which the recipient assumes is an active agent.

independent variable

in an experiment, the factor that is manipulated; the variable whose effect is being studied.

confounding variable

a factor other than the factor being studied that might influence a study's results.

dependent variable

in an experiment, the outcome that is measured; the variable that may change when the independent variable is manipulated.

validity

the extent to which a test or experiment measures or predicts what it is supposed to.

informed consent

giving potential participants enough information about a study to enable them to choose whether they wish to participate.

debriefing

the postexperimental explanation of a study, including its purpose and any deceptions, to its participants.

descriptive statistics

numerical data used to measure and describe characteristics of groups. Includes measures of central tendency and measures of variation.

histogram

a bar graph depicting a frequency distribution.

mode

the most frequently occurring score(s) in a distribution.

mean

the arithmetic average of a distribution, obtained by adding the scores and then dividing by the number of scores.

median

the middle score in a distribution; half the scores are above it and half are below it.

skewed distribution

a representation of scores that lack symmetry around their average value.

range

the difference between the highest and lowest scores in a distribution.

standard deviation

a computed measure of how much scores vary around the mean score.

normal curve

a symmetrical, bell-shaped curve that describes the distribution of many types of data; most scores fall near the mean (about 68 percent fall within one standard deviation of it) and fewer and fewer near the extremes.

inferential statistics

numerical data that allow one to generalize from sample data the probability of something being true of a population.

statistical significance

a statement of how likely it is that an obtained result occurred by chance.

neuron

a nerve cell; the basic building block of the nervous system.

cell body

the part of a neuron that contains the nucleus; the neuron's lifesupport center.

dendrites

a neuron's often bushy, branching extensions that receive and integrate messages, conducting impulses toward the cell body.

axon

the neuron extension that passes messages through its branches to other neurons or to muscles or glands.

myelin sheath

a fatty tissue layer segmentally encasing the axons of some neurons; enables vastly greater transmission speed as neural impulses hop from one node to the next.

glial cells

cells in the nervous system that support, nourish, and protect neurons; they also play a role in learning, thinking, and memory.

action potential

a neural impulse; a brief electrical charge that travels down an axon.

threshold

the level of stimulation required to trigger a neural impulse.

refractory period

in neural processing, a brief resting pause that occurs after a neuron has fired; subsequent action potentials cannot occur until the axon returns to its resting state.

all-or-none response

a neuron's reaction of either firing (with a fullstrength response) or not firing.

synapse

the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron.

neurotransmitters

chemical messengers that cross the synaptic gaps between neurons. When released by the sending neuron they travel across the synapse and bind to receptor sites on the receiving neuron, thereby influencing whether that neuron will generate a neural impulse.

reuptake

a neurotransmitter's reabsorption by the sending neuron.

endorphins

"morphine within"—natural, opiate-like neurotransmitters linked to pain control and to pleasure.

agonist

a molecule that increases a neurotransmitter's action.

antagonist

a molecule that inhibits or blocks a neurotransmitter's action.

nervous system

the body's speedy, electrochemical communication network, consisting of nerve cells

central nervous system

the brain and spinal cord.

peripheral nervous system

the sensory and motor neurons that connect the central nervous system (CNS) to the rest of the body.

nerves

bundled axons that form neural cables connecting the central nervous system with muscles, glands, and sense organs.

sensory (afferent) neurons

neurons that carry incoming information from the body's tissues and sensory receptors to the brain and spinal cord.

motor (efferent) neurons

neurons that carry outgoing information from the brain and spinal cord to the muscles and glands.

interneurons

neurons within the brain and spinal cord; they communicate internally and process information between the sensory inputs and motor outputs.

somatic nervous system

the division of the peripheral nervous system that controls the body's skeletal muscles. Also called the skeletal nervous system.