The Science of Psychology
Chapter 1
Psychology as a Science
•Psychology - scientific study of behavior
and mental processes
•Goals of Psychology
•describe behavior
•explain behavior
•predict behavior
•control “some” behavior
The Fields of Psychology
Developmental Psychology
Studies changes that accompany age
• child psychologists
• gerontologists
• life-span psychologists
Physiological Psychology
Studies Biological basis of behavior
• neuropsychology
• psychobiology
• genetics and heredity
Experimental Psychology
Research on basic psychological
processes:
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learning
memory
perception
emotion
Personality Psychology
• study differences among individuals
• develop theories about the causes of
these differences
• use tests and questionnaires to measure
these differences
Social Psychology
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How do people influence one another?
group behavior
leadership
altruism
conformity and obedience
Industrial & Organizational
Psychology
I/O psychologists are interested in
• selecting and training personnel
• improving productivity and working
conditions
• stress and other worker problems
• Designing products for comsumer
convenience, safety, appeal
Clinical & Counseling Psychology
(Applied Psychology)
• Clinical psychologists - diagnosis, cause,
and treatment of psychological disorders.
• Counseling psychologists - “normal”
problems of adjustments in life.
Areas by Profession
Clinical
Counseling
Education/
School
Industrial/
Organizational
Other
•More than half of all psychologists work in
“Applied” areas such as clinical
Professional Associations
1. American Psychological Association
(APA)
largest organization, founded in 1892
2. American Psychological Society (APS)
founded in 1988, more “research” focused
Enduring Issues in Psychology
Person vs. Situation
Nature vs. Nurture
Stability vs. Change
Determinism vs. Free Will
The “mind - body” problem
Psychology is a Science
• Scientific Method – generate theory-based testable hypotheses
– collect data
– use data to further develop the theory
• Theory - systematic organization of facts
relating to a general area (big bang theory)
• Hypothesis - A specific testable prediction
(planets are moving apart)
The History of Psychology
• Psychology is only about 100 years old
• It developed out of two other sciences
Philosophy
Physiology
Psychology
The Growth of Psychology
• Beginning in the late 1800s different
“schools of thought” developed, first in
Europe and later in the United States
Structuralism: Wilhelm Wundt
• Wundt is considered by many to be the
“father of psychology”
• Wundt opened the first psychological
laboratory in Liepzig, in 1879
• Goal - to discover the basic units of
conscious “atoms of thought” To discover
the mind’s “structure”
• Method - Objective introspection
Functionalism: William James
• Consciousness is constantly “flowing like a
river” and cannot be broken into “atoms of
thought”
• James felt that Wundt left out
the“associations” of consciousness
• Goal - to understand how our senses allow
us to “function” in the environment
Psychoanalysis: Sigmund Freud
• First modern personality theorist
• Focused on the unconscious
determinants of behavior
• Freud developed a method of therapy
called psychoanalysis
• Psychoanalysis is also Freud’s theory of
personality and method of research
• biologically “deterministic” little free will
Behaviorism: Watson & Skinner
• Founder - John B. Watson
• Goal - Psychologists should study only
“observable behaviors”
• Watson & Raynor’s (1921) “Little Albert
Study” demonstrated that Pavlov’s classical
conditioning works in humans
• B. F. Skinner - focused on Operant
(Instrumental) conditioning in which the
learner plays an active role
• Environmentally “Deterministic” little free
will
Cognitive Psychology
• Has grown rapidly since the1950s, thoughts
are considered behaviors and therefore open
to scientific study
• Often views the brain within a “computer”
model with input, output, storage, etc.
• Concerned with memory, thinking,
language, learning, decision making
Gestalt: Max Wertheimer
• Goal - to understand how we “perceive”
objects in our world
• Gestalt - means “whole” or good form
• Law of Pragnanz - We tend to see things in
the simplest possible way
• Gestalt Principles - closure, similarity,
proximity, continuity, etc.
Gestalt Principles of Grouping
• proximity:
• similarity:
Gestalt Principles of Grouping
• closure: filling in a
figure’s gaps to
create a whole object
Humanistic: Carl Rogers
• Humanism - An optimisitc view of human
nature. Developed in the 1940s-50s in
response to the “determinism” of
psychoanalysis and behaviorism
• People are basically good and strive to
reach their full potential
• Optimistic view, we have free will
Existentialism: Rollo May
• Based on existential philosophy
• Concerned with the “alienation” and “lack
of meaning” in our modern technological
society.
• Addresses difficult questions such as What
is the “meaning of life.”
Evolutionary Psychology
• studies the evolutionary origins of
behaviors and characteristics
• their adaptive value
• how they change over time to meet the
demands of the environment
Positive Psychology
• A recent addition to the field
• Focuses on the characteristics that
make people happy and successful
• Asserts that psychology has, in the
past, focused too much on the negative
Research Methodologies
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Naturalistic Observation
Case Studies
Surveys and Questionnaires
Correlational Research
Experimental Research
Naturalistic Observation
Observing and recording the behavior of
people (or animals) in their natural
environment
Advantages
• we see behavior as
it naturally occurs
• no “artificial”
laboratory setting
Disadvantages
• cannot control all
variables
• possible observer
biases or error
Case Studies
• In depth description and analysis of a
single individual (or a few individuals).
• Main Advantage - detailed understanding of
human phenomena such as serial killing (e.g.,
Jeffrey Dahmer, or Charles Manson)
• Main Disadvantages - costly , time
consuming, inaccurate retrospective
inforamtion
Survey/Questionnaires
Questionnaires or Surveys are administered
to a large group of people.
Advantages
Disadvantages
• much information
• inexpensive
• fast and efficient
• response biases
• quality of responses
Correlational Research
• Correlation - Number that indicates the
relationship between two or more variables
• Values - can range from -1 to +1
• Scatterplot: visually represents a correlation
• When a strong correlation exists, one variable
(SAT score) can be used to PREDICT the
value of a second variable ( college GPA)
Correlation (cont.)
• +1 indicates a perfect positive relationship
• (e.g., X = Y)
• Example - Hours studying and GPA
• -1 indicates a perfect negative relationship
• (e.g., X = -Y)
• Example - Hours partying and GPA
• 0 indicates no relationship
• Example - IQ and shoe size
Correlation (cont.)
• In the real world +1 and -1 are really seen.
• Values will range between 0 and + or - 1
• Two variables may correlate highly but that
does NOT mean one variable caused the
other
“CORRELATION DOES NOT EQUAL
CAUSATION”
Experimental Method
• the experimenter deliberately
manipulates a variable (e.g., therapy
vs. no therapy)
• the effect of that manipulation on
another variable (e.g., depressive
symptoms) is then measured
Experimental Research
• independent variable: variable that is
manipulated by the experimenter
• dependent variable: variable that is
measured to see the effect of the
independent variable (e.g., does
therapy group get better?)
Experimental Research
• experimental group: receives some
“treatment” like getting a drug or
psychotheray
• control group: treated exactly the same as
the experimental group but does NOT
receive the “treatment”
• random assignment: subjects must be
assigned to groups randomly to avoid “bias”
Choosing the Sample
• sample: group of participants selected
to represent the population
• random sample: each member of the
population has an equal chance of being
selected for the sample
• representative sample: makeup of the
sample (e.g., proportion of males and
females) matches the population
Experimental Research
• Advantages
• Disadvantages
• conclusions about
• ethical issues
causality can be
• lab situation is
made
“artificial” and
• unwanted variables
results may not
can be controlled or
generalize to the
eliminated
“real world”
Stanley Milgram’s Obedience Study
• 1963 social psychology experiment,
subjects thought they were shocking another
person to promote “learning”
• Many subjects delivered high level shocks
and were upset when they later learned the
true nature of the experiment
• This study, and other factors, led to much
more stringent APA resarch guidlines
APA Ethical Guidelines (humans)
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informed consent
awareness of risks
confidentiality
deception can be used ONLY if benefits
justify it and there is no other way to do the
study
APA Ethical Guidelines (animals)
• Researchers must ensure “appropriate
consideration of [the animal’s]
comfort, health, and humane
treatment.”
• Animals may not be subjected to “pain
or stress” when an alternative
procedure is available.