Download Psychology: Pavlov, Watson, Skinner

Psychology: Pavlov,
Watson, Skinner
Learning Experiments and
Concepts
Classical Conditioning
• PAVLOV’S DOG
Classical conditioning was accidentally discovered
around the beginning of the 20th century by Russian
physiologist Ivan Pavlov. Pavlov was studying digestive
process in dogs when he discovered that the dogs
salivated before they received their food. In fact, after
repeated pairing of the lab attendant and the food, the
dogs started to salivate at the sight of the lab assistants.
Pavlov coined this phenomena “psychic secretions." He
noted that dogs were not only responding to a biological
need (hunger), but also a need developed by learning.
Pavlov spent the rest of life researching why this
associate learning occurred, which is now called
classical conditioning.
Pavlov’s Dog
Classical Conditioning
• PAVLOV’S DOG
To experiment on classical conditioning, Pavlov utilized a
tuning fork and meat powder. He hit the tuning fork and
followed the sound with the meat powder. Pavlov
presented the sound (tuning fork) with the meat powder
at the exact same time increments. In the beginning, the
dog salivated only to the meat powder, but after this was
repeated, salivated at the sound of the tuning fork. Even
when Pavlov took away the meat powder, the dog
continued to salivate at the sound of the tuning fork.
Classical Conditioning
• PRINCIPLES OF CLASSICAL
CONDITIONING
In classical conditioning, an organism
learns to associate one stimulus with
another. The organism learns that the first
stimulus is a cue for the second stimulus.
In Pavlov’s experiment above, the tuning
fork cued the dogs that food might be
coming. Following is an example of
classical conditioning.
Classical Conditioning
Classical Conditioning
• PAVLOV’S DOG
In technical terms, the food is an unconditioned
stimulus (UCS) and the salivation is the
unconditioned response (UCR). The bell is a
neutral stimulus until the dog learns to associate
the bell with food. Then the bell becomes a
conditioned stimulus (CS) which produces the
conditioned response (CR) of salivation after
repeated pairings between the bell and food.
Pavlov’s Dog
Classical Conditioning Works On
People, too
Classical Conditioning
• WATSON’S BABY ALBERT
John B. Watson was interested in how classical
conditioning could be applied to humans. In 1921,
Watson and his research assistant Rosalie Rayner
experimented on a 11-month-old infant named Albert.
The goal was to condition Albert to fear a white rat by
paring the white rat with a loud bang (UCS). Initially,
Albert showed no fear of rats, but once the rat was
repeatedly paired with the loud noise (UCS), Albert
developed a fear of rats. The noise (UCS) induced fear
(UCR). After pairings between the loud noise (UCS) and
the rat (CS), Albert started to fear the rat. Watson’s
experiment suggested that classical conditioning could
cause some phobias.
John Watson’s Little Albert
Experiment
CLASSICAL CONDITIONING
• KEY CONCEPTS OF CLASSICAL CONDITIONING
• Unconditioned Stimulus (UCS)
A stimulus that elicits a response without conditioning
Unconditioned Response (UCR)
Automatic response elicited by the unconditioned stimulus
Conditioned Stimulus (CS)
A neutral stimulus that when paired with an unconditioned stimulus
(UCS) elicits a similar response
• Conditioned Response (CR)
A response that is learned by pairing the originally neutral
conditioned stimulus (CS) with the
unconditioned stimulus (UCS)
Perhaps
Psychology’s
most famous
Experiment
CLASSICAL CONDITIONING
•
Acquisition
The acquisition phase is the consistent parings of the CS (bell) and the UCS
(food) that produces a CR (salivation). In the example above, this phase
occurs when the dog begins to salivate at the sound of the bell.
Conditioning occurs more rapidly when the food follows the bell by a half a
second.
•
Extinction
The extinction phase is when the conditioned response no longer occurs
after repeated pairings without the unconditioned stimulus. The dog’s
response to the bell can be extinguished by repeatedly presenting the bell
(CS) without the food (UCS). The dog has not completely forgotten the
association between the bell and the food. If the experimenter waits a day,
the dog may have a spontaneous recovery of the conditioned response and
salivate again to the bell.
CLASSICAL CONDITIONING
• Generalization
Occurs when there is a small difference in the presented stimulus
and the original conditioned stimulus. If Pavlov’s dog heard a bell of
a similar tone, the dog would still salivate.
• Discrimination
The opposite of generalization, discrimination happens when a
conditioned response does not occur when there is a difference
between the presented stimulus and the original conditioned
stimulus. If Pavlov’s dog heard a bell with a different tone and was
not awarded the unconditioned stimulus (food), the dog would learn
not to salivate to the second tone.
Operant Conditioning
• SKINNER’S OPERANT CONDITIONING
Beginning in the 1930’s, Skinner started his experimentation on the
behavior of animals. Skinner's quest was to observe the relationship
between observable stimuli and response. Essentially, he wanted to
know why these animals behaved the way that they do. Skinner
controlled his experiments by using “Skinner boxes.” The Skinner
box was a contraption that would automatically dispense food
pellets and electric shocks. Skinner believed that the learning he
observed in his Skinner boxes could apply to human behavior. He
called this learning operant conditioning. Operant conditioning can
be described as behavior adjustments as a result of greater or
lesser negative or positive reinforcement and punishment. Skinner
hypothesized that human behaviors were controlled by rewards and
punishment and that their behaviors can be explained by principles
of operant conditioning
Operant Conditioning
Operant Conditioning
• PRINCIPLES OF OPERANT
CONDITIONING
• The main principles of operant
conditioning, as defined by Skinner, are
reinforcement, punishment, shaping,
extinction, discrimination, and
generalization.
Punishers
Punisher
• Ok, who wasn’t expecting that?
Operant Conditioning
• KEY CONCEPTS OF OPERANT CONDITIONING
• Reinforcement
The process in which a behavior is strengthened, and
thus, more likely to happen again.
• Positive Reinforcement
Making a behavior stronger by following the behavior
with a pleasant stimulus. For example, a rat presses a
lever and receives food.
• Negative Reinforcement
Making a behavior stronger by taking away a negative
stimulus. For example, a rat presses a lever and turns off
the electric shock
Positive Reinforcement
Punisher
Negative Reinforncement
B.F. Skinner
Operant Conditioning
•
Punishment
The process in which a behavior is weakened, and thus, less likely to
happen again.
•
Negative Punishment
Reducing a behavior by removing a pleasant stimulus when the behavior
occurs. If the rat was previously given food for each lever press, but now
receives food consistently when not pressing the lever (and not when it
presses the lever), the rat will learn to stop pressing the lever.
•
Positive Punishment
Reducing a behavior by presenting an unpleasant stimulus when the
behavior occurs. If the rat previously pressed the lever and received food
and now receives a shock, the rat will learn not to press the lever.
Operant Conditioning
• Shaping
Technique of reinforcement used to teach new behaviors. At the
beginning, people/animals are reinforced for easy tasks, and then
increasingly need to perform more difficult tasks in order to receive
reinforcement. For example, originally the rat is given a food pellet
for one lever press, but we gradually increase the number of times it
needs to press to receive food, the rat will increase the number of
presses.
• Extinction
The elimination of the behavior by stopping reinforcement of the
behavior. For example, a rat who received food when pressing a bar,
receives food no longer, will gradually decrease the amount of lever
presses until the rat eventually stops lever pressing.
Shaping
Operant Conditioning
• Generalization
In generalization, a behavior may be performed in more
than one situation. For example, the rat who receives
food by pressing one lever, may press a second lever in
the cage in hopes that it will receive food.
• Discrimination
Learning that a behavior will be rewarded in one
situation, but not another. For example, the rat does not
receive food from the second lever and realizes that by
pressing the first lever only, he will receive food.
• Fast Facts About
IVAN PAVLOV
(1849- 1936)
Pavlov
Pavlov
• Ivan Petrovich Pavlov was born on September 14, 1849, in Ryazan,
Russia.
Pavlov’s father was the local priest and worked in the fields with his
mother during the day.
• In 1870, Pavlov abandoned his studies in religion and enrolled in the
University of St. Petersburg. Inspired by the ideas of I.M. Sechenov,
the father of Russian physiology, he enrolled in natural science
courses.
• In 1875, he graduated with a degree of Candidate of Natural
Sciences; however, wanting more education in physiology, Pavlov
enrolled in the Academy of Medical Surgery. In 1879, he was
awarded another gold medal.
• In 1881, Pavlov married Seraphima Vasilievna Karchevskaya, a
teacher and had five children: Wirchik, Vladimir, Victor, Vsevolod,
and Vera. Wirchik died in childhood.
Pavlov
• In 1890, Pavlov was appointed as a professor at
St. Petersburg Military-Medical Academy.
• During 1891-1900, at the Institute of
Experimental Medicine, Pavlov conducted his
research on the physiology of digestion.
• In 1901, Pavlov was elected as corresponding
member of the Russian Academy of Sciences.
• In 1904, during his Nobel Prize address, Pavlov
introduced his findings on conditioned reflexes.
Pavlov
• In 1907, Pavlov was elected Academician
of the Russian Academy of Sciences.
• In 1912, Pavlov received an honorary
doctorate degree from Cambridge
University.
• In 1915, Pavlov was awarded the Order of
the Legion of Honour.
• Pavlov died on February 27, 1936 in
Leningrad.
• Fast Facts About
JOHN B. WATSON
(1878-1958)
Watson
• John Broadus Watson was born on January 9, 1878, near
Greenville, South Carolina to Emma and Pickens Watson.
• Watson's mother, who was very religious, named John after a local
minister.
• Watson's father, Pickens, had extra-marital affairs and left the family
in 1891.
• With the absence of his father during childhood, Watson often
rebelled and was once arrested for shooting a gun.
Watson
• Watson was accepted to Greenville’s Furman University as a subfreshman.
• Watson had planned to attend Princeton Theological Seminary to
become a clergyman but was held back a year for handing in his
philosophy-psychology exam backwards.
• In an attempt to upstage his instructor, Gordon Moore, Watson
decided to pursue a Ph.D. in philosophy-psychology (something
Moore did not have).
• With the help of Moore, Watson was admitted to the philosophypsychology department at the University of Chicago. It was at the
University of Chicago where Watson began his experiments on
animals.
Watson
• Watson received his doctorate at the University of Chicago in 1903.
At the University of Chicago, Watson was a departmental star being
the youngest student with a Ph.D. at the university and had the
second-best final exam in the history of the department.
• Watson married Mary Ickes in December 1903. They had two
children, Mary and John.
• In 1903, Watson accepted a professor of psychology position at
Johns Hopkins University.
• After a year at John Hopkins University, Watson became the
department leader and editor of the Psychological Review.
Watson
• In 1913, Watson published the article “Psychology as the
Behaviorist Views It."
• In 1915, Watson became the President of the American
Psychological Association.
• Watson enlisted in the Signal Corps in 1917 during
World War I.
• In 1920, he published his experiments on “Little Albert”
with Rosalie Rayner.
• John Hopkins University forced Watson to resign after
finding out that he had an affair with Rayner. Watson and
Mary divorced and married Rayner. Watson and Rayner
had two children, James and William.
Watson
• Watson was offered a job at the J. Walter
Thompson advertising agency for $25,000 a
year (four times his professor’s salary). In 1924,
Watson became vice-president of the agency.
• Watson continued to publish psychological
works, but stopped in the 1930s to focus on his
advertising career.
Watson died in 1958.
• Fast Facts About
B.F. SKINNER
(1904 – 1990)
Skinner
• Burrhus Fredrick Skinner was born on March 20,
1904, in Susquehanna, Pennsylvania.
• His father was a self-taught lawyer and his
mother a housewife.
• As a boy, Skinner showed great mechanical
skills by designing a device to separate ripe and
green berries and a contraption to remind him to
keep his room clean.
• Skinner published his first work “That
Pessimistic Fellow,” a poem, in Lone Scout
magazine at the age of ten.
Skinner
• In 1922, Skinner attended Hamilton College in Clinton, New York.
• After graduating from Hamilton, Skinner decided that he wanted to
become a writer and moved back with his parents. Skinner later
called this period the “dark year” because he experienced a severe
case of writers block.
• During a stay in New York, Skinner happened to read the works of
Watson and Pavlov. He was impressed with their work and sought to
learn more.
• In 1928, at the age of 24, Skinner applied and was accepted into
Harvard’s psychology program.
Skinner
• While at Harvard, Skinner invented Skinner box and the
cumulative recorder which made it possible for Skinner
to study animal behavior. The cumulative recorder
logged the number of bar presses. Skinner noticed that
the number of bar presses was dependent on what was
received following the bar presses and not the preceding
stimulus. Skinner called this behavior, "operant
conditioning."
• In 1936, Skinner married Yvonne Blue. They had their
first child, Julie, in 1938.
• In 1944, during World War II, Skinner worked on the
“Project Pigeon” which trained pigeons to direct bombs
by pecking at a target.
Skinner
• In 1943, during Yvonne’s second pregnancy,
Skinner designed the “baby tender,” a crib that
was designed to be safer than a normal crib.
• In 1945, Skinner became Chair of the
Psychology Department at the University of
Indiana.
• In 1948, Skinner joined Harvard University’s
psychology department.
• Skinner died on August 18, 1990, from leukemia.