Download Chap 6 Learning

Chapter 6
Learning
Key Terms for Learning
• Learning: Relatively durable change in
behavior due to experience
– Does NOT include temporary changes due to
disease, injury, maturation, or drugs, since these
do NOT qualify as learning even though they can
alter behavior
• Reinforcement: Any event that increases the
probability that a response will recur
• Response: Any identifiable behavior
– Internal: Faster heartbeat
– Observable: Eating, scratching
Classical Conditioning
Sovfoto
Ideas a of classical conditioning originate from old
philosophical theories, however it was a Russian
physiologist Ivan Pavlov who elucidated classical
conditioning. His work became seminal for later
behaviorists like John Watson and B. F. Skinner.
Ivan Pavlov (1849-1936)
Classical Conditioning (or Pavlovian Conditioning)
• Classical Conditioning is a type of learning in
which a stimulus acquires the capacity to evoke a
response that was originally evoked by another
stimulus.
• Ivan Pavlov was a Russian physiologist who was
originally studying digestion in dogs.
• Used dogs to study salivation when dogs were
presented with meat powder
Pavlov’s Experiments
During conditioning, neutral stimulus (tone) and US
(food) are paired resulting in salivation (UR). After
conditioning neutral stimulus (now Conditioned
Stimulus, CS) elicits salivation (now Conditioned
Response, CR)
The classical conditioning procedure.
Classical Conditioning: More Terminology
• Trial = pairing of UCS and CS
• Acquisition = initial stage in learning
• Stimulus contiguity = occurring together in
time and space
!
• Classical Conditioning in Everyday Life
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Conditioned fears
Other conditioned emotional responses
Conditioning and physiological responses
Conditioning and drug effects – F 6.6
Processes in Classical Conditioning
• Extinction: when the CS is weakened
• Spontaneous Recovery: when an extinct CS recurs
when paired with the UCS.
• Stimulus Generalization: when we respond to similar
to the original UCS
• Discrimination: when we respond to a specific
stimulus
• Higher-order conditioning: when a CS has the same
effect as a UCS and establishes new conditioning.
• Applications of classical conditioning – Pavlov and
persuasion: the use of images and products in
advertising
Classical Conditioning in Humans
• Phobia: Fear that persists even when no realistic
danger exists (e.g., arachnophobia (fear of spiders;
see the movie!))
• Conditioned Emotional Response (CER): Learned
emotional reaction to a previously neutral stimulus
• Desensitization: Exposing phobic people gradually to
feared stimuli while they stay calm and relaxed
• Vicarious Classical Conditioning: Learning to respond
emotionally to a stimulus by observing another’s
emotional reactions
Applications of Classical Conditioning
Brown Brothers
Watson used classical
conditioning procedures to
develop advertising campaigns
for a number of organizations
including Maxwell House,
making “coffee break” an
American custom.
John B. Watson
The Little Albert Experiment
• Little Albert and John Watson
• John Watson in a famous (and perhaps
unethical) experiment conditioned “Little
Albert” to fear a white rat. Albert
generalized this conditioning to other white
furry objects. Nobody knows what
eventually happened to Little Albert.
Operant Conditioning or
Instrumental Learning
• Edward L. Thorndike (1913) – the Law of
Effect: If a response to a stimulus is
pleasant, the association between
stimulus and response is strengthened
• B. F. Skinner – most influential figure in
Psychology
– Operant Conditioning: reinforcement
occurs when an event following a response
increases an organism’s tendency to make
that response.
Basic Processes in Operant
Conditioning
Shaping consists of reinforcement of closer
and closer approximations of a desired
response.
• Extinction is the gradual weakening and
disappearance of a response when a
reinforcer is no longer provided
• Stimulus Generalization occurs when a
response occurs to stimuli other than the
original stimulus used in conditioning
• Stimulus Discrimination occurs when no
response is given to a similar stimuli.
Table 6.1 Comparison of Basic Processes in Classical and Operant
Conditioning
Operant & Classical Conditioning
1. Classical conditioning
forms associations
between stimuli (CS and
US). Operant
conditioning on the
other hand forms
association between
behaviors and resulting
events.
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Reinforcement: Consequences that
Strengthen Responses
• Delayed Reinforcement
– Longer delay, slower conditioning
• Primary Reinforcers
– Satisfy biological needs
• Secondary Reinforcers
– Conditioned reinforcement
Schedules of Reinforcement
• Continuous reinforcement
• Intermittent (partial) reinforcement
• Ratio schedules
– Fixed: reinforced after a specific number of responses.
– Variable: reinforced after an undetermined number of
responses.
• Interval schedules
– Fixed: reinforced after a specific amount of time.
– Variable: reinforced after a varying amount of time
Schedules of Reinforcement
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Consequences: Reinforcement and
Punishment
• Increasing a response:
– Positive reinforcement = response followed by
rewarding stimulus
– Negative reinforcement = response followed by
removal of an aversive stimulus
• Escape learning
• Avoidance learning
• Decreasing a response:
– Punishment
– Problems with punishment – third variable problem
and correlation between punishment and aggression
Reinforcement in a token
economy. This graph shows the
effects of using tokens to reward
socially desirable behavior in a
mental hospital ward. Desirable
behavior was defined as
cleaning, bed making, attending
therapy sessions, and so forth.
Tokens earned could be
exchanged for basic amenities
such as meals, snacks, coffee,
game-room privileges, or
weekend passes. The graph
shows more than 24 hours per
day because it represents the
total number of hours of
desirable behavior performed by
all patients in the ward.
(Adapted from Ayllon & Azrin,
1965.)
A Token Economy
Fig. 8.15 Poker
chips normally
have little or no
value for
chimpanzees, but
this chimp will
work hard to earn
them once he
learns that the
“Chimp-O-Mat” will
dispense food in
exchange for
them.
Operant vs. Classical Conditioning
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Observational Learning: Basic
Processes
• Albert Bandura (1977, 1986)
– Observational learning – F 6.24
– Vicarious conditioning
• 4 key processes
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attention
retention
reproduction
motivation
• acquisition vs. performance
Observational Learning and the
Media Violence Controversy
• Studies demonstrate that exposure to TV
and movie violence increases the
likelihood of physical aggression, verbal
aggression, aggressive thoughts, and
aggressive emotions
• The association between media violence
and aggression is nearly as great as the
correlation between smoking and cancer –
F 6.26 – third variable problem
Comparison of the relationship between media violence and
aggression to other correlations.