Chapter 6: Learning
Classical Conditioning
• Ivan Pavlov
• Terminology
– Unconditioned Stimulus (UCS): evokes
an unconditioned response without
previous conditioning (meat powder)
– Conditioned Stimulus (CS): a previously
neutral stimulus that has, through
conditioning, acquired the capacity to
evoke a conditioned response (bell after
conditioning)
Classical Conditioning
– Unconditioned Response (UCR): an
unlearned reaction to an unconditioned
stimulus that occurs without previous
conditioning (salivation before
conditioning)
– Conditioned Response (CR): a learned
reaction to a conditioned stimulus that
occurs because of previous
conditioning (salivation after
conditioning)
Classical Conditioning
• Neutral Stimulus: does not evoke a response
(bell)
Figure 6.1 Classical conditioning apparatus
Figure 6.2 The sequence of events in classical conditioning
Figure 6.3 Classical conditioning of a fear response
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: More Terminology
• 3 types of Classical Conditioning
– Simultaneous conditioning: CS and UCS
begin and end together
– Short-delayed conditioning: CS begins
just before the UCS, end together
– Trace conditioning: CS begins and ends
before UCS is presented
Processes in Classical Conditioning
• Extinction: the gradual weakening and
disappearance of a conditioned response
• Spontaneous Recovery: reappearance of
an extinguished response after a period of
nonexposure to the conditioned stimulus
Processes in Classical Conditioning
• Stimulus Generalization: the organism
that has learned a response to a specific
stimulus responds in the same way to
stimuli that are similar to the original
stimulus
• Stimulus Discrimination: the organism
that has learned a response to a specific
stimulus does not respond in the same
way to stimuli that are similar to the
original stimulus
• Higher-order conditioning
Figure 6.7 Acquisition, extinction, and spontaneous recovery
Figure 6.10 Higher-order conditioning
Operant Conditioning
or Instrumental Learning
• Edward L. Thorndike (1913) – the law of
effect
• B.F. Skinner (1953) – principle of
reinforcement
– Operant chamber
– Emission of response
– Reinforcement contingencies
– Cumulative recorder
Figure 6.12 Reinforcement in operant conditioning
Figure 6.13 Skinner box and cumulative recorder
Basic Processes in Operant Conditioning
• Acquisition
• Shaping: consists of the reinforcement of
closer and closer approximations of a
desired response
• Extinction: in operant conditioning this
occurs if we stop providing reinforcement.
• Stimulus Control
– Generalization
– Discrimination
Table 6.1 Comparison of Basic Processes in Classical and Operant Conditioning
Reinforcement:
Consequences that Strengthen Responses
• Primary Reinforcers
– Satisfy biological needs
• Secondary Reinforcers
– Conditioned reinforcement
Schedules of Reinforcement
• Continuous reinforcement
• Intermittent (partial) reinforcement
– Ratio schedules
• Fixed (piece work on assembly line)
• Variable (slot machine)
– Interval schedules
• Fixed (paycheck every two weeks)
• Variable (fishing)
Figure 6.17 Schedules of reinforcement and patterns of response
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
Figure 6.18 Positive reinforcement versus negative reinforcement
Figure 6.19 Escape and avoidance learning
Figure 6.20 Comparison of negative reinforcement and punishment
Changes in Our Understanding
of Conditioning
• Biological Constraints on Conditioning
– Instinctive Drift
– Conditioned Taste Aversion
– Preparedness and Phobias
• Cognitive Influences on Conditioning
– Signal relations
– Response-outcome relations
• Evolutionary Perspectives on learning
Figure 6.22 Conditioned taste aversion
Observational Learning: Basic Processes
• Albert Bandura (1977, 1986)
– Observational learning: an organism’s
response is influenced by the
observation of others
– Vicarious conditioning
• 4 key processes
– attention
– retention
– reproduction
– motivation
• acquisition vs. performance
Figure 6.25 Observational learning