Early Influences on Behaviorism
Towards a Science of Behavior
The Early Years: Behavorism & Animal
Psychology
• By the 1920’s psychologists had rejected; introspection as a
scientific method, the existence of mental elements, and the
need for psychology to be a pure science.
• Functionalism and applied psychology dominated American
psychology
• In 1913 John B. Watson set out to deliberately challenge
both structuralism and functionalism.
• Watson received his Ph.D. in 1903 from James Angell at
the University of Chicago, also studied with John Dewey.
• “the the study of scientific psychology should concern itself
only with behavioral acts that could be described
objectively”
The Early Years: Behaviorism & Animal
Psychology
• consciousness & mind could never be proved
objectively, therefore studying consciousness has no
value.
• rejected the study of all mentalistic concepts and terms
like images, consciousness, and mind.
• Introspection is therefore useless for studying behavior.
• These basic ideas were not necessarily new.
• The times were also ripe for the development of a new
psychology that focused only on observable behavior.
• The three major factors that contributed were the
philosophies of Mechanism & Positivism, Functional
Psychology, and early Animal Psychology.
Animal Intelligence
• Physiologists had long found it of interest to compare similarities
in body function between animals and human beings.
• Two early psychologists George John Romanes (1848-1894), and
C. Loyd Morgan (1852-1936) studied animal minds, using
observational techniques as opposed to experimental techniques.
• The first true investigator of animal intelligence using
experimental techniques was Jacques Loeb (1859-1924).
• Loeb developed a theory of animal behavior based on trophism,
or involuntary movement.
• Loeb believed animal reactions to stimulus were direct and
automatic, thus behavioral response was said to be forced by the
stimulus and did not require any consciousness explanation.
• Animal memory was said to develop through associationism (e.g.
associative memory)
Margaret Floy Washburn (1871-1939)
Titchener’s first doctoral
student.
 came to Cornell after being
denied admission to Columbia
Universities graduate program.
 first woman to receive a
doctorate in psychology and
the second woman president of
the American Psychological
Association.
 Washburn went on to a
distinguished career at Vassar
College where she became the
second woman in any science
ever elected to the National
Academy of Sciences

Margaret Floy Washburn (1871-1939)
• concerned with the inference of
consciousness in animals.
• wrote the first important book
on comparative psychology,
Animal Mind, in 1908.
• She published hundreds of
experiments on animals that
included sensory
discriminations, spatially
determined reactions, and
modification by experience.
• Washburn is considered by
many scholars to be the first
comparative psychologist
Robert Yerkes (1876-1956)
• the most prominent of the early comparative
psychologists.
• eventually referred to as the “dean of comparative
psychology”
• He published his first paper on the effects of light
on freshwater crustacean in 1899
• The first journal of research with animals the
Journal of Animal Behavior was not published
until 1911.
• The problems of paying for, keeping, and
maintaining animals was an important an issue in
the 1900’s as it is today, and animal psychologists
were often expendable because of the issue.
Robert Yerkes (1876-1956)
• attended Harvard University where he took
his degree with Hugo Munsterburg in 1899.
• at Harvard as an instructor and assistant
professor of comparative Psychology then
moved to the University of Minnesota.
• Yerkes would go on to an eminent career in
psychology, eventually becoming president
of the American Psychological Association
in 1916.
• During the WW1 Years Yerkes was
extremely important in involving
psychologists in the war effort.
Robert Yerkes (1876-1956)
•
•
WW1 The Committee on the Psychological Examination of Recruits
WW2 he also was the organizer of the emergency committee of
psychologists
The Committee on the
Psychological Examination of
Recruits- May, 1917
The Emergency Committee, 1940
Edward Lee Thorndike (1874-1949)
• Thorndike was one of the most important
early theorists in animal learning,
educational psychology, and behavioral
psychology.
• Thorndike developed the “law of effect” in
1898, several years earlier than Ivan Pavlov
proposed his law’s of reinforcement.
• Although the theories are almost identical
the two individuals were not aware of each
other for many years.
Edward Lee Thorndike (1874-1949)
• Thorndike introduced to psychology at
Wesleyan University in Connecticut, he
attended Harvard university for his
Master’s degree where he studied with
and was influenced by William James.
• He left Harvard for Columbia University
in 1898, where he completed his doctorate
under James Cattell in 1899.
• one of the first psychologists to complete
his education entirely in America.
• major contributions to psychology were in
the area of educational psychology.
Edward Lee Thorndike (1874-1949)
• two main foci in education were 1) the
improvement of classroom instruction and 2) the
measurement of the learner and the products of
learning.
• wrote three books for his own use that became
classics in educational psychology 1) Educational
Psychology (1903), 2) The Theory of Mental and
Social Measurement (1904), and a three volume
Educational Psychology (1913).
• wrote Thorndike Arithmetic's and the Teachers
Word Book (1921) which had an enormous
influence in American psychology and education.
• founded the Journal of Educational Psychology in
1910.
The Law of Effect
• referred to his approach to learning as
connectionism, hypothesized that an organism
learned about connections between situations and
types of responses.
• one of the first to hypothesize that “if all of these
(responses & situational variables) could be
analyzed” man could be told what would and would
not satisfy him and annoy him in every conceivable
situation.
• The law of effect refers to “stamping in or stamping
out” a response tendency by attaching favorable or
unfavorable consequences.
• the law of effect states “any act which in a given
situation produces satisfaction becomes associated
with that situation, and when the situation reoccurs
the act is more likely to reoccur than before”.
Ivan Pavlov (1849-1936)
• Ivan Petrovitch Pavlov born 1849 in Central
Russia.
• son of a village priest and eldest of 11 children.
• initially intended to enter a theological seminary
but after reading about Darwinian evolution
changed his mind and enrolled at the University
of St. Petersburg to study animal physiology.
• He obtained his degree in 1875 and began to
study medicine in the hopes of becoming a
physiologist.
• In 1890 he received an appointment as professor
of pharmacology at St. Petersburg Military
Academy
Ivan Pavlov
An early picture of Pavlov, His Staff, and
Research Apparatus
Ivan Pavlov (1849-1936)
• worked in 3 major areas: 1) The
function of nerves on the heart, 2) the
function of the primary digestive
glands, and 3) the conditioned reflex.
• Although it is the last area for which he
is best remembered, his work on the
digestive glands won him worldwide
recognition and the 1904 Nobel prize
for medicine.
• His work on the conditioned reflex
represents an excellent example of how
significant accidents often play a major
role in the history of science.
Classical Conditioning 1
Will the dog learn to associate
the arrival of food with a neutral
stimulus (e.g., a bell)?
Classical Conditioning 2
Terms
Unconditioned Response
Unconditioned Stimulus
Conditioned Response
Conditioned Stimulus
UCR - drool in response to food (not learned)
UCS - food (triggers drool reflex)
CR - drool in response to sound of bell (learned)
CS - sound of bell (triggers drool reflex)
Applications of Classical Conditioning
Is human behavior nothing more
than a bunch of conditioned
behaviors?
Case of “Little Albert”
John Watson
UCS
Loud Noise
UCR
Fear
CS
White Rat
CR
Fear
Rare Early Photos of John Watson & Rosalie Rayner
Beginning Conditioning With Little Albert (1920).
John Watson (1878-1958)
B. F. Skinner (1904-1990)
B. F. Skinner
(1904-1990)
Skinner’s Experiments
Favorite Subjects
Rats & Pidgeons
Favorite Operatus
Skinner Box
Fave Procedure
Shaping
Shaping
Guiding current behavior
toward some desired
behavior through
successive approximations
B. F. Skinner (1904-1990)
Skinner elaborated on Thorndike’s
Law of Effect
“Rewarded behavior is likely
to reoccur”
B. F. Skinner
(1904-1990)
External influences,
not internal thoughts
& feelings, govern
E. L. Thorndike
behavior.
Principles of Reinforcement
Reinforcer - any event that
increases the frequency of the
preceding event
Positive Reinforcers Negative Reinforcers
Introduce (+) stimulus Remove (-) stimulus
(e.g., food)
(e.g., electric shock)
Reinforcers ALWAYS strengthen behavior!
More Reinforcement
Primary Reinforcers
Innately satisfying,
Not learned
(e.g., getting food)
Secondary Reinforcers
Associated with primary
reinforcers & learned
(e.g., praise)
Reinforcers ALWAYS strengthen behavior!
Still More Reinforcement
Immediate
Reinforceme
nt
Reinforce
immediately
preceding
behavior (e.g.,
nicotine)
Delayed Reinforcement
Reinforcement at some point
after behavior occurs
(e.g., paychecks)
Reinforcers ALWAYS strengthen behavior!
Reinforcement Schedules
Continuous - every time behavior occurs (rare)
or
Partial - not every time behavior occurs
(learning is slower but more resistant to extinction)
Partial Reinforcement
(a pidgeon will peck 150,000 times without reward)
Behavior-Based Reinforcers
Fixed Ratio - reinforce every n responses
Variable Ratio - reinforce after ?? responses
Time-Based Reinforcers
Fixed Interval - reinforce after fixed time
Variable Interval - reinforce after ?? time
Punishment
Opposite of
Reinforcement
Attempts to decrease
behavior by introducing
an unpleasant punisher
Problems With Punishment
• Behavior is not forgotten - merely suppressed
(may reappear in other situations)
• P does not guide toward acceptable behavior
(doesn’t tell you what you should do)