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Unit V: Learning
Learning
A relatively permanent
change in an organism’s
behavior due to
experience.
We learn by association.
– Our minds naturally
connect events that occur
in sequence.
Associative Learning
Learning that two
events occur
together.
– Two stimuli
– A response a nd
its consequences.
Classical Conditioning
A basic form of learning in
which a stimulus that
produces an innate reflex
becomes associated with
a previously neutral
stimulus, which then
acquires the power to elicit
essentially the same
response.
– The tapping of the yardstick
on the desk causes you to
flinch. .
Classical Conditioning
Ivan Pavlov first
demonstrated
classical conditioning.
His work provided a
basis for later
behaviorists like John
Watson and B. F.
Skinner.
Classical Conditioning and
Pavlov’s Dogs: Hypothesis
Dogs salivate when food
is placed in their mouths
(a reflex).
Dogs salivate at the
mere sight of food
Hypothesis: Dogs can be
trained, or conditioned,
to salivate when
exposed to an external,
neutral stimulus.
Pavlov’s Methodology and Results
Harness an untrained
dog and place a vial to
collect saliva.
Sound a bell immediately
before giving a bit of food
Results: After a few
trials, the dog salivates
upon hearing the bell
alone.
Works with other stimuli
as well; buzzer,
metronome etc.
Pavlov’s Experiment
Before conditioning,
food (Unconditioned
Stimulus, US)
produces salivation
(Unconditioned
Response, UR).
However, the tone
(neutral stimulus)
does not.
Pavlov’s Experiment
During conditioning, the
neutral stimulus (tone)
and the US (food) are
paired, resulting in
salivation (UR).
After conditioning, the
neutral stimulus (now
Conditioned Stimulus,
CS) elicits salivation
(now Conditioned
Response, CR)
Pavlov’s Conclusions
Unconditioned
Response
(UCR)
because
of
Unconditioned
Stimulus
(UCS)
Conditioned
Response
(CR)
because
of
Conditioned
Stimulus
(CS)
Garfield
Classical Conditioning
NEUTRAL STIMULUS
will
elicit
NO REACTION
UNCONDITIONED STIMULUS
will
elicit a
REFLEX ACTION
will
elicit a
REFLEX ACTION
will
elicit a
CONDITIONED
RESPONSE
UNCONDITIONED STIMULUS
NEUTRAL STIMULUS
CONDITIONED
CONDITIONEDSTIMULUS
STIMULUS
Classical Conditioning Vocabulary
Unconditioned Stimulus - UCS
– stimulus that
unconditionally-automatically and naturally-triggers a response
– Unlearned.
Unconditioned Response
(UCR)
 Unlearned, naturally
occurring response to the
unconditioned stimulus
 salivation when food is
in the mouth.
Classical Conditioning Vocabulary
Conditioned Stimulus (CS)
– originally irrelevant
stimulus that, after
association with an
unconditioned stimulus,
comes to trigger a
conditioned response
Conditioned Response (CR)
– learned response to a
previously neutral
conditioned stimulus
Pavlov’s Homeroom
Other Aspects of Classical Conditioning
Acquisition
– The first stage in classical conditioning.
– The phase associating a neutral stimulus with an
unconditioned stimulus so that the neutral stimulus comes to
elicit a conditioned response.
– In most cases, for conditioning to occur, the neutral stimulus
needs to come just before the unconditioned stimulus.
• The time in between the two stimuli should be about half a
second.
Other Aspects of Classical Conditioning
Extinction
– Diminishing of a CR; when the CS occurs repeatedly without the UCS.
– The tone is heard several times without the food following.
Other Aspects of Classical Conditioning
Spontaneous Recovery
– After a rest period, an extinguished CR spontaneously recovers.
– However, if the CS persists alone, the CR will become extinct
again.
Other Aspects of Classical Conditioning
Stimulus Generalization
– The tendency to respond
to stimuli similar to the CS.
Other Aspects of Classical Conditioning
Stimulus Discrimination
– Discrimination is the
learned ability to
distinguish between a
conditioned stimulus
and other irrelevant
stimuli.
• Pavlov’s dogs did not
respond to other
sounds.
Cognitive Processes
Early behaviorists believed
that learned behaviors of
various animals could be
reduced to mindless
mechanisms.
However, later behaviorists
suggested that animals learn
the predictability of a
stimulus, meaning they learn
expectancy or awareness
Biological Predispositions
 Pavlov and Watson believed
that laws of learning were
similar for all animals.
Therefore, a pigeon and a
person do not differ in their
learning.
 However, behaviorists later
suggested that learning is
constrained by an animal’s
biology.
Conditioned Taste Aversions
Can you think of a
food that you once
had a bad experience
with that still produces
a feeling of nausea
when you encounter
it?
– Can you think of a
benefit to food
aversions?
Taste-Aversion Learning
The tendency to
develop taste
aversions appears to
be part of our
biological nature.
– Raises questions
about Pavlov’s
original Classical
Conditioning theory.
John Garcia
Garcia showed that the time
duration between the CS and the
US may be long (hours), but yet
result in conditioning.
Rats avoid drinking or eating from
containers that made them sick.
– They associated flavored water
with illness.
Pavlov’s Legacy
Pavlov’s greatest
contribution to
psychology is isolating
elementary behaviors
from more complex
ones through objective
scientific procedures.
Applications of Classical Conditioning
Watson used classical
conditioning procedures to
develop advertising
campaigns for a number
of organizations, including
Maxwell House, making
the “coffee break” an
American custom.
Operant Conditioning
The consequences of behavior,
such as reinforcers and
punishments, influence the
chance that the behavior will
occur again.
Reward
– Behavior change is brought about
by the consequences of behavior.
– Also a form of associative
learning.
An “operant” is an observable
behavior that an organism uses to
have an effect on their
environment.
Punishment
B.F. Skinner
The “founding father” of
operant conditioning.
American psychologist
who based his entire
career on the idea that
the most powerful
influences on behavior
are its consequences.
Reinforcement
Reinforcer: Any condition that follows and
strengthens a response.
– Positive: Strengthens a response by occurring after the
response and making the behavior more likely to occur
again.
• Praise, attention, money, food etc.
– Negative: The removal of an unpleasant or averse stimulus.
• Negative = subtract or remove
• Using an umbrella in a rainstorm. Buckling your seatbelt.
The Skinner Box
A simple device for studying
the effects of reinforcers on
laboratory animals.
A box with a lever that an
animal could press to obtain
food.
– Could be set to control the
timing and frequency of the
reinforcement.
Skinner called it an “operant
chamber.”
Contingencies of Reinforcement
The timing and frequency of
rewards are crucial.
Continuous Reinforcement: A
reward is given for every correct
response.
– The best strategy for teaching
and learning new behaviors.
– Does have drawbacks:
• Accidental failure to reward a
correct response could be
misinterpreted.
• Will loose its reinforcing quality
as the organism becomes
satisfied.
Shaping
Shaping: Used to create
complex new behaviors
because the teacher can
continually “raise the bar”
and increase the
standards required for
earning a reward.
– It tells the learner when
progress is being made.
– An example of continuous
reinforcement.
Intermittent Reinforcement
The rewarding of
some, but not all,
correct responses.
– Also known as partial
reinforcement.
The best way to
maintain behaviors
that have already been
learned.
– Helps resist extinction.
Schedules of Reinforcement
The ratio schedule rewards a subject after a certain
number of responses.
Fixed Ratio (FR): Receive a reward after a specific
number of responses.
– For example, one dollar for every 5 paper roses produced;
piecework
Variable Ratio (VR): Ever changing number of
responses needed to receive a reward.
– Produces more responding than any other schedule of
reinforcement.
– Slot machines.
Interval Schedules
Reinforcement is based on responses made within a certain
time period (instead of number of responses.)
Fixed Interval (FI) Schedules: The time period between
rewards remains constant.
– A monthly paycheck for example.
– Produces lowest level of responses.
Variable Interval (VI) Schedules: The time interval between
rewards varies. The most unpredictable of all.
– For example, fishing and elevators.
Schedules of Reinforcement
Interval
Fixed
Variable
Ratio
Primary and Secondary Reinforcers
Primary: Reinforcers such as
food, water and sex that have
an innate basis because of
their biological value to the
organism.
Secondary: Stimuli, such as
money or grades, that acquire
their reinforcing power by a
learned association with a
primary reinforcer.
– Also called Conditioned
Reinforcers.
The Premack Principle
A more-preferred activity
can be used to reinforce a
less-preferred activity.
– Sit still during a lesson so
that you can run around
during recess time
afterwards.
– Discovered by David
Premack.
The Problem of Punishment
It is an aversive consequence used to weaken the
behavior it follows.
– Acts as the opposite of reinforcement.
Comes in two forms:
– Positive Punishment: requires the application of an averse
stimulus.
– Negative Punishment: The removal of a reinforcer.
• Omission training.
Must be administered consistently!
– Not punishing an occurrence of unwanted behavior can have
the effect of rewarding it.
Problems with Punishment
Punishment usually doesn’t work well in the long
run. Why?
– The power of punishment to suppress behavior usually
disappears when the threat of punishment is removed.
– Punishment triggers escape or aggression.
– Punishment makes the learner apprehensive, which
inhibits learning new and better responses.
• Learned helplessness.
– Punishment is often applied unequally.
When Using Punishment
When punishment is used it
must be:
– Swift
– Consistent
– Limited in duration and
intensity
– Clearly targeted on the
behavior
– Limited to the situation in
which the behavior occurred
– Giving clear, not mixed
messages
The most effective punishment
is usually omission training.
Punishment vs. Negative Reinforcement
An animal in a Skinner Box
can turn off a loud noise by
pressing a lever.
– Negative Reinforcement;
Used to increase the
behavior.
A loud noise plays when
the same animal presses a
lever.
– Punishment; used to
decrease the behavior.
Operant Conditioning
Reinforcement Punishment
Positive
(Add)
Chocolate Bar
Electric Shock
Negative
(Remove)
Excused from
Chores
No TV
privileges
Skinner’s Work
Play Skinner Video
Cognitive Explanations
Many theorists believe
not all learning can be
explained with
behaviorism.
– There is a cognitive
element to some learning.
– Some learning must be
explained as changes in
mental processes, rather
than just changes in
behavior.
Insight Learning
Wolfgang Kohler studied
chimpanzees during WWI. He
found:
– Once chimps solved a problem
they would do the same thing in a
similar situation.
– Chimps “thought out” their
solutions ahead of time.
– They often reached a solution
suddenly.
He called this insight learning; a
sudden understanding about
what is required to solve a
problem.
Insight Learning
Edward Tolman
Latent Learning: learning that is
not evident when it first occurs.
Tolman’s rats had late rewards.
The food rewards affected
performance, but not learning.
Rats had already developed a
cognitive map; a mental
representation of the
environment (the maze.)
– They had developed it
naturally, without
reinforcement.
Observational Learning
Observational Learning:
learning how to perform
new behaviors by
watching others.
– Also known as social
learning.
– Efficient and adaptive.
– Modeling is the process of
observing and imitating a
specific behavior.
Mirror Neurons
Mirror neurons in our brains
fire not only when we
experience or do something,
but also when we see
someone else do or
experience the same thing.
– We feel disgust when we see
someone react to the taste of
sour milk.
– May partly provide a
biological basis for
observational learning.
Bandura’s Study
Children are particularly influenced by
the adults and peers who act as models
for appropriate behavior in various
situations.
Bandura showed preschool school
children a film of an adult and a large
“Bobo” doll.
– The children who saw the adult
rewarded for aggression toward the doll
showed the most aggressive acts in
their own play.
– Vicarious Learning: a kind of
observational learning in which a person
is influenced by seeing or hearing about
the consequences of other people’s
behavior.
Social Learning Theory
Some key aspects of Bandura’s theory include:
– People learn from observation of others, however, this can depend
on the amount of attention that is given to the behavior.
– The person whose behavior is being observed is called a model.
– Learning takes place without effort; however, the observer must be
paying attention.
– Reinforcement is not necessary for learning to take place; however,
it does determine whether the behavior is imitated.
– Reinforcements and punishments can be vicarious; if the model’s
behavior has a pleasurable outcome it is more likely to be repeated
by the observer.
– The learner may receive reinforcements or punishments for
imitating the model, this also affects behavior.
– Some models are more likely to be imitated than others
Watch Bandura’s Study
Play Film Clip
Observational Learning
Seems to be a
powerful source of
the socialization
process through
which children learn
about which
behaviors are, and
are not, appropriate
in their cultures.