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Learning
Learning is defined as a persistent,
enduring change in behavior or
knowledge due to experience.
Acquisition
• How do we acquire new knowledge or skills?
– Conditioning
• A process of learning associations between environmental
events and behavioral responses.
• Two types
– Classical – involves automatic or reflexive behavior
– Operant – involves the acquisition of new voluntary actions
– Social Learning
• The acquisition of learning through the observation of others
What’s this about
LEARNING?
Classical
Conditioning
Ivan Pavlov
• Russian physiologist
• Nobel Prize for work on digestion
• His studies of dogs led to classical conditioning
Pavlov’s Dogs
• Digestive reflexes
and salivation
• Acquisition: The
application of Laws
of Association in the
formation of new
conditioned reflexes
Classical Conditioning
• Behaviors that are classically conditioned are those which
involve the learning of involuntary responses
• Responses over which the learner has no control and to which
he or she responds reflexively or "automatically."
• Examples include
– a dog salivating at the sound of the dinner bell
– someone becoming nauseous at sight of "creamy-looking" food
when mayonnaise once made them ill, etc.
• Pairing of a neutral stimulus (NS) with unconditioned
stimulus (natural) to elicit an unconditioned response (UCR)
• It usually takes repeated pairings before a neutral stimulus
becomes a conditioned stimulus (CS) no longer needs the
reinforcing properties of the uncond. Stimulus (UCS) to
elicit a cond. Response (CR)
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
Neutral Stimulus (NS)
Bell
• Does not normally elicit a response
or reflex action by itself
– A bell ringing
– A color
– A furry object
Unconditioned Stimulus (UCS)
Food
• Always elicits a reflex action: an
unconditioned response
– Food
– Blast of air
– Noise
Unconditioned Response (UCR)
Salivation
• A response to an unconditioned
stimulus--naturally occurring
– Salivation at smell of food
– Eye blinks at blast of air
– Startle reaction in babies
Conditioned Stimulus (CS) - Bell
• The stimulus that was originally
neutral becomes conditioned after it
has been paired with the
unconditioned stimulus
• Will eventually elicit the
unconditioned response by itself
Conditioned Response (CR)
• The original unconditioned
response becomes conditioned
after it has been elicited by the
neutral stimulus without the UCS
John B. Watson and Little Albert
• Conditioned Albert to fear fuzzy things
• Watson believed in only the study of observable behavior
and that everything is learned from environmental factors
• NS
– White rat
• UCS
– Loud noise
• UCR
– Fear
• CS
– White rat
• CR
– Fear of rat
•Various Procedures for Pairing the CS and US in Classical Conditioning
•Delay pairing, where there is an
overlap in the presentation of CS
and US leads to the best
conditioning.
•Trace pairing, where there is a
delay between onset of US and the
end of the CS leads to good
conditioning. Less than 2 seconds
•Simultaneous pairing of CS and
US, interstimulus interval = 0, leads
to poor conditioning.
•Backward pairing, where the US
is presented first and then followed
by the CS leads to poor
conditioning.
•
Two Theoretical Models Of Classical
Conditioning
• Contiguity
– Based on the work of
Pavlov
– Conditioning will
occur whenever a CS
and a UCS are paired
• Contingency
– Based on the work of
Robert Rescorla and
Allan Wagner
– The CS must reliably
predict the UCS for
conditioning to occur
– Attention is important
– Studies in blocking by
Leon Kamin supports
this theory
Let's review these concepts.
• Unconditioned Stimulus: a thing that can already elicit a
response.
• Unconditioned Response: a thing that is already elicited by a
stimulus.
• Unconditioned Relationship: an existing stimulus-response
connection.
• Conditioning Stimulus: a new stimulus we deliver the same time
we give the old stimulus.
• Conditioned Relationship: the new stimulus-response
relationship we created by associating a new stimulus with an
old response.
• There are two key parts. First, we start with an existing
relationship, Unconditioned Stimulus ---> Unconditioned
Response. Second, we pair a new thing (Conditioning Stimulus)
with the existing relationship, until the new thing has the power
to elicit the old response
Classical Conditioning
Phenomenon
•
•
•
•
Extinction
Spontaneous recovery
Generalization
Discrimination
• Extinction: A procedure for the elimination of a conditioned reflex. After a
period where the CS is not paired with the UCS.
– Examples: teacher ignoring student's disruptive behavior in order not to give her
attention; a girl ignoring phone calls (i.e., using caller i.d. or answering machine to
find out who's calling and not picking up the phone if its an unwelcome caller),
etc.)
• Spontaneous Recovery: An extinguished behavior reoccurs (responding to
the CS) after rest period.
• Generalization: After an organism is conditioned to respond to a stimulus, it
also responds, though less strongly, to different, but similar stimuli, forming
a stimulus generalization.
• Discrimination: After conditioning a response to a stimulus, similar stimuli
do not elicit that response. Discrimination is believed to be based upon
inhibition, a more complete discussion of both generalization and
discrimination is included in our investigation of instrumental
conditioning.
• Higher-Order Conditioning
– Higher-order conditioning is the chaining of conditioned
stimuli, so that the CS, in turn, signals another CS.
– The procedure involves a CS being paired with a US
(UCS) so that it elicits a CR and then that CS is paired
with another neutral CS.
– After a few trials the new CS is able to elicit the CR
without ever being paired with the original US.
• Conditioned Emotional Response:
– Disruption of ongoing behavior due to exposure to a CS
that elicits fear.
Behavioral Therapy or Modification:
• Systematic desensitization: Establishes positive CR, for example
relaxation, in the place of negative ones such as fear or anxiety.
Slowly expose them to their fears + relax
• Flooding: The client is exposed with an aversive or anxiety producing
CS but the avoidance response is blocked, until the client relaxes.
Throw them into the water
• Aversion therapy: The drug (CS) is paired with emetic (US) causing
vomiting (UR) leading to the client hating or avoiding the drug.
– Pair a nausea producing drug (antabuse) with alcohol
• Counter-Conditioning:
– Counter-Conditioning involves the substitution of a new behavior for an old one,
after a CR is acquired, the organism is conditioned to a new CR that is contrary
to the nature of the original CR.
• Teaching relaxation techniques to have a person relax instead of fear things like
spiders and snakes
• example
Early Operant Conditioning
• Edward L. Thorndike (1898)
• Puzzle boxes and cats
• Instrumental Learning
– An organism’s behavior is instrumental in
producing an environmental change that
in turn affects the organism’s behavior
– Law of Effect
• Behaviors are encouraged when they are
followed by rewarding consequences and
discouraged when followed by punishing
consequences
B.F. Skinner’s Operant Conditioning
• Burrhus Friederich Skinner
• Did not like the term “satisfying”
• Invented a better appartus--the
Skinner box
Operant Conditioning Terms
• Shaping
– Technique whereby successive approximations of a
geometric figure are reinforced
– When trying to train people or animals to be able to
perform difficult tasks you reward them along the way
• Chaining
– Reinforcing them only after they have done a number of
tasks
• Consequences
– positive and negative reinforcement
– Punishment
– Omission
These can occur in Operant Conditioning
•
•
•
•
•
•
Extinction
Spontaneous Recovery
Discrimination
Generalization
Acquisition
Association
Types of Reinforcers
• Primary
– Basic needs being met
• Food, water, waste reduction, sleep etc.
• Stimulus needs as well such as curiosity, manipulation and
exploration
• Secondary
– Reinforcers that are associated with or used to acquire
primary reinforcers
• Money, tokens, power
• They have to be learned
• Punishment
–
–
–
–
Aversive Conditioning
Usually causes hatred of the enforcer
Effective punishment is often intense and immediate
Usually only creates a temporary suppression of the undesired behavior
Can reinforce the use of aggressive behavior to attain goals
• Negative Reinforcement
– Responding the correct way to avoid an unwanted reinforcer
– Two types
• Escape (During)
– Behavior to stop an aversive event
– Taking an aspirin to stop a headache
• Avoidance (Before)
– Behavior occurs when a signal warns the individual that an aversive event is likely
– Taking aspirin prior to a stressful day
• Learned Helplessness
– Decrease in responding that occurs after exposure to uncontrollable aversive
events. You can’t escape or avoid
– Martin Seligman believes the Learned Helplessness helps explain depression
and some poor job performance
Reinforcement Schedules
• Continuous: 1 to 1 ratio, a prize every time
• Intermittent/Partial- only some correct
responses are rewarded
– Ratio- number of responses must occur before
being reinforced
• fixed: 1 to ?, a prize every ? time
• variable: ? to ?, maybe a prize, maybe not!
– Interval- amount of time must occur before being
reinforced
• fixed: announced examination
• variable: pop quiz
Classical vs. Operant
Conditioning
CLASSICAL
OPERANT
• Stimulus precedes the
response and elicits it
• Elicited responses
• Learning as a result of
association
• Pavlov and Watson and
Mary Cover Jones
• Stimulus follows the
response and
strengthens it
• Emitted responses
• Learning as a result of
consequences
• Skinner and Thorndike
The Basic Concepts of Learning
Theory
• Classical conditioning
– elicits response as a result of associating
• unconditioned stimulus
• neutral stimulus
• Operant conditioning
– emitted response
– learning is a result of consequences
• reinforcers
• punishment
Observational Learning
 Albert Bandura’s cognitive theory
Social Learning Theory
• People can learn by observing the behavior of others
and the outcomes of those behaviors.
• Learning can occur without a change in behavior,
because people can learn through observation
alone.
• Cognition plays a role in learning. Over the last 30
years social learning theory has become increasingly
cognitive in its interpretation of human learning.
• Awareness and expectations of future reinforcements
or punishments can have a major effect on the
behaviors that people exhibit.
• Social learning theory can be considered a bridge or a
transition between behaviorist learning theories and
cognitive learning theories.
Modeling and SLT
• The observer is reinforced by the model.
– a student who changes dress to fit in with a certain group of
students has a strong likelihood of being accepted and thus
reinforced by that group.
• The observer is reinforced by a third person.
– The observer might be modeling the actions of someone
else, for example, an outstanding class leader or student.
The teacher notices this and compliments and praises the
observer for modeling such behavior thus reinforcing that
behavior.
• Many behaviors that we learn from others produce
satisfying or reinforcing results.
– a student in my multimedia class could observe how the
extra work a classmate does is fun. This student in turn
would do the same extra work and also receive enjoyment.
• Consequences of the model’s behavior affect
the observers behavior vicariously. This is
known as vicarious reinforcement.
• Bandura illustrated this by having students
watch a film of a model hitting a inflated
clown doll.
• One group of children saw the model being
praised for such action. Without being
reinforced, the group of children began to
also hit the doll .