Learning: Ch 7
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Definition: Learning is defined as relatively permanent changes in behaviour
resulting from experience and from practice
o Single trial learning
o Long duration learning and skilled behaviour
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A vast amount of our overt as well as covert behaviour (how we think) is learned
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If a behaviour is learned the general view is that we should be able to change or
re-shape it
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This is the basis for many forms of behavioural therapy
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As behaviour becomes over-learned, fewer attentional resources are required to
carry out tasks (skilled performance) and processing moves to the right brain
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As a behavioural concept, learning takes the form of an intervening variable
(between independent and dependent)
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Thus learning can’t be directly observed – only indirectly e.g. improved speed,
fewer errors, etc
Types of Learning
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Habituation
Observational
Complex learning
Classical conditioning
Operant or Instrumental learning
Classical Condition
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also called associative or contiguity learning
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Identified by Ivan Pavlov (1884 – 1936)
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Pavlov was a Russian physiologist researching digestive processes – he was using
dogs as a model
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Russia’s first Nobel Prize winner (1904) for work on digestive processes
Classical conditioning involves:
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The autonomic nervous system (sympathetic and parasympathetic) and its’
corresponding involuntary smooth muscles
Classical conditioning requires:
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A stimulus for which the meaning is innately understood (e.g. food, water,
warmth, pleasure, pain) unconditioned stimulus (UCS)
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A second contiguous neutral stimulus (NS) which initially has no specific
meaning (e.g. a bell) but which has the capacity to invoke an orienting type
response
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As the UCS and NS are presented contiguously (close together in time) on
successive occasions, the NS becomes a predictor of the UCS
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Once the NS is interpreted by an organism as reliably predicting the UCS, the NS
is raised to the status of a conditioned stimulus (CS)
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Thus classical conditioning has occurred when a previously meaningless NS has
become a CS (that is a stimulus now regulating a behavioural response)
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Note: to obtain classical conditioning, a NS must precede an UCS by at least 0.5
seconds
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Acquisition: UCS and CS pairings create stimulus associations
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Extinction: lack of UCS and CS pairings cause associations to disappear
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Spontaneous Recovery: reappearance of learning after extinction
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Note: the general concepts (acquisition, extinction) also apply to operant learning
Operant Learning
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Operant or Instrumental learning was first identified in North America in the early
1900’s
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Based on the work of Watson and Thorndike
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Thorndike’s Law of Effect stated that rewarded behaviour is more likely to
reoccur
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BF Skinner (1904 – 1990)
Physiological mechanisms:
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Skeletal and voluntary striated muscles
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CNS and PNS
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The overall framework for learning is response / reinforcement (R-R)
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Distinct from classical conditioning with its’ stimulus / response (S-R) framework
Terminology:
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Shaping: Learning in gradual steps
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Reinforcement: a stimulus event that increases the likelihood of a response
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Primary reinforcer: innate reinforces e.g. food, water, warmth, pleasure
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Secondary reinforcer: learned reinforcers e.g. money, praise, good grades, status
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Positive reinforcement: increasing the likelihood of a response by administering
a pleasant stimulus (e.g. if you get good grades I will buy you a new car)
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Negative reinforcement: increasing the likelihood of a response by removing an
adverse stimulus (e.g. if you get good grades you can stay out later on Friday and
Saturday nights)
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Punishment: decreasing the likelihood of response by administering an adverse
stimulus (e.g. if you obtain poor grades you will be grounded for a semester)
Schedules of reinforcement:
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These refer to the pattern of responding required for reinforcement and are of 2
general types:
1) Ratio schedules: reinforcement is contingent on the number of responses
generated since the last reinforcer
2) Interval schedules: reinforcement is contingent on the time that has elapsed since
the last reinforcer
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Ratio and Interval schedules can be further categorized as fixed or variable
1) Fixed: reinforcement is contingent on a fixed number of responses or a fixed
amount of time since the last reinforcer
2) variable: reinforcement is contingent on a variable number of responses or a
variable amount of time since the last reinforcer
Four basic schedules of reinforcement:
Fixed
Variable
Ratio
1) Fixed Ratio
2) Variable Ratio
Interval
3) Fixed Interval
4) Variable Ratio
Two Process Learning:
Learning where a classically conditioned response controls or moderates an operant or
instrument al response
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The onset of a classically conditioned fear response to a buzzer (CS) motivates an
avoidance response (operant bar pressing)
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The subsequent termination of the buzzer and shock (UCS) reinforces future
avoidance response (operant)
Learned Helplessness:
The failure to avoid or escape from an unpleasant or aversive stimulus that occurs as a
result of previous exposure to unavoidable painful stimuli is referred to as learned
helplessness. Learned helplessness, which has been demonstrated in both animals and
humans, is associated with many of the symptoms characteristic of depression
Stimulus Generalization and Discrimination: