1 Scientific Foundations

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.)

critical thinking

thinking that does not blindly accept arguments and conclusions. Rather, it examines assumptions, discerns hidden values, evaluates evidence, and assesses conclusions.

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 statement of the procedures (operations) used to define research variables. For example, human intelligence may be operationally defined as what an intelligence test measures.

replication

repeating the essence of a research study, usually with different participants in different situations, to see whether the basic finding extends to other participants and circumstances.

case study

an observation technique in which one person is studied in depth in the hope of revealing universal principles.

naturalistic observation

observing and recording behavior in naturally occurring situations without trying to manipulate and control the situation.

survey

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

sampling bias

a flawed sampling process that produces an unrepresentative sample.

population

all the cases in a group being studied, from which samples may be drawn. (Note: Except for national studies, this does not refer to a country's whole population.)

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 thingsto things (from -1 to +1).

scatterplot

a graphed cluster of dots, each of which represents the values of two variables. The slopeslop of the points suggests the direction of the relationship between the two variables. The amount of scatter suggests the strength of the correlation (little scatter indicates high correlation).

illusory correlation

the perception of a relationship where none exists.

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, the experimenter aims to control other relevant factors.

experimental group

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

control group

in an experiment, the group that is not exposed to the treatment; contrasts with the experimental group and serves as a comparison for evaluating the effect of the treatment.

random assignment

assigning participants to experimental and control groups by chance, thus minimizing preexisting differences between those assigned to the different groups.

double-blind procedure

an experiment procedure in which both the research participants and the research staff are ignorant (blind) about whether the research participants have received the treatment or a placebo. Commonly used in drug-evaluation studies.

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

the experimental factor that is manipulated; the variable whose effect is being studied.

confounding variable

a factor other than the independent variable that might produce an effect in an experiment.

dependent variable

the outcome factor; the variable that may change in response to manipulations of the independent variable.

validity

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

descriptive statistics

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

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

representation of scores that lack symmetry around their average value

range

the difference between the highest and lower 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 (68% fall within one standard deviation of it) and fewer and fewer near the extremes

inferential statistics

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

statistical significance

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

culture

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

informed consent

an ethical principle that research participants be told enough to enable them to choose whether they wish to participate.

debriefing

the post experimental explanation for a study, including its purpose and any deceptions, to its participants.

regression toward the mean

the tendency for extreme or unusual scores or events to fall back (regress) toward the average

histogram

a bar graph depicting a frequency distribution

Standard deviations to the nearest tenth

34.1%, 13.6%, 2.1%, 0.1%

empiricism

the view that knowledge originates in experience and that science should, therefore, rely and observation and experimentation.

structuralism

an early school of psychology that used introspection to explore the elemental structure of the human mind

functionalism

a school of psychology that focused on how our mental and behavioral processes function and how they enable us to adapt, survive and flourish

experimental psychology

the study of behavior and thinking using the experimental method

behaviorism

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

humanistic psychology

historically significant perspective that emphasized the growth potential of healthy people and individual's potential for fostering personal growth

cognitive neuroscience

the interdisciplinary study of the brain activity linked with cognition (including 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. Today's science sees traits and behaviors arising from the interaction of nature and nurture

natural selection

the principle that, among the range of inherited variation, those contributing to reproduction and survival will most likely be passed on to succeeding generations.

levels of analysis

the differing complementary views, from biological to psychological to social-cultural, for analyzing any given phenomenon

biopsychological approach

an integrated approach that incorporates biological, psychological, and social-cultural levels of analysis

behavioral psychology

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

biological psychology

a branch of psychology that studies the links between biological (genetic, neural, and hormonal, including neuroscience and behavior genetics) and psychological processes

cognitive psychology

the scientific study of all the mental activities associated with thinking, knowing, remembering, and communicating

evolutionary psychology

the study of the roots of behavior and mental processes using the principles of natural selection

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.

psychometric

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

the scientific study of 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 individual's characteristics patternpatter 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 organization (I/O) psychology

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

human factors psychology

the study of how people and machines interact and the design of safe and easily used machines and environments.

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 sometimes provide medical (for example, drug) treatments as well as psychological therapy.

positive psychology

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

community psychology

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

testing effect

enhanced memory after retrieving, rather than simply rereading, information; sometimes referred to as a retrieval practice effect or test-enhanced learning.

SQ3R

a study method incorporating five steps: survey, question, read, rehearse, review.

critical thinking

Thinking that does not blindly accept arguments and conclusions. Rather, it examines assumptions, appraises the source, discerns hidden biases, evaluates evidence and assesses conclusions.

introspection

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

behaviour genetics

the study of the relative power and limits of genetic and environmental influences and behaviour

culture

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

Wilhelm Wundt

• Structuralist

• Established the first psychology laboratory at the University of Leipzig, Germany

• Studied “atoms of the mind”

• G. Stanley Hall’s and Edward Bradford Titchener’s Teacher

G. Stanley Hall

• Structuralist

• Studied the “atoms of the mind” under Wundt

• Established the first US psychology laboratory at Johns Hopkins University

Edward Bradford Titchener

• Structuralist

• Wundt’s student

• Introduced Structuralism to search for the mind’s structural elements

William James

• Functionalist

• Considered the evolved functions of our thoughts and feelings

• Studied down-to-earth emotions, memories, willpower, habits and moment-to-moment streams of consciousness

• As functionalist, opposed structuralism

Charles Darwin

• Darwin stated that nature selects those that best enable the organism to survive and reproduce in a particular environment

• Survival of the fittest

• Nature versus nurture

Mary Whiton Calkins

• Functionalist

• Student of William James

• First female president of American Psychological Association

• Became pioneering memory researcher

Margaret Floy Washburn

• Functionalist

• First woman to receive a psychology PhD

• Synthesized animal behaviour research in Animal Mind (1908)

John. B Watson

• Behaviourist

• Dismissed introspection and redefined psychology as “the scientific study of observable behaviour”

B. F. Skinner

• Leading Behaviourist

• Rejected introspection and studied how consequences shape behaviour

Sigmund Freud

• Controversial ideas of this famed personality theorist and therapist have influenced humanity’s self-understanding

• Psychoanalytic approach

• Emphasized the effect of unconscious mind and childhood experiences on behaviour

Carl Rogers

• Humanistic psychologist

• Humanistic

• Found both behaviourism and Freudian psychology too limiting

• Rather than focusing on conditioned responses or childhood memories, humanistic psychologists focused on our potential for personal growth

Abraham Maslow

• Humanistic psychologist

• Humanistic

• Found both behaviourism and Freudian psychology too limiting

• Rather than focusing on conditioned responses or childhood memories, humanistic psychologists focused on our potential for personal growth

Ivan Pavlov

• Behaviourist

• Pioneered the study of learning

Jean Piaget

• Swiss biologist

• Last century’s most influential observer of children

Dorothea Dix

• Led the way to humane treatment of those with psychological disorders

Socrates and Plato

• Dualism: believed that the mind was separate from the body

• Ideas believed to be innate

• Mind believed to continue to exist after death

Aristotle

• Suggested that the soul is not separable from the body and that knowledge and ideas grow from experience

Rene Descartes

• Like Socrates and Plato, believed in soul/mind-body separation, but wondered how the immaterial mind and physical body communicated

• Memories open pores in the brain

• “Animal spirits”

Francis Bacon

One of the founders of modern science, particularly the experimental method

John Locke

Argued that the mind was a tabula rasa (blank slate) at birth and experiences wrote on it