OUTLINE
Lecture 3: Basic Concepts in Animal Learning
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1. What is Associative Learning?
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Associative learning is the learning of associations (relationships)
between stimuli (events).
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Conditioning: process by which stimuli and behavior become
associated with each other
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Stimulus: a localized event, such as the onset of a light or a key, or
the presentation of a tone from a speaker.
Pavlovian Conditioning (Classical Conditioning)
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Unconditioned Stimulus (US).
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Unconditioned Response (UR)
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Conditioned Stimulus (CS)
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Conditioned Response (CR)
Instrumental Conditioning (Operant Conditioning)
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Edward L. Thorndike’s puzzle boxes.
- Positive Reinforcement
- Positive Punishment (Punishment)
- Negative Reinforcement
- Negative Punishment (Omission)
- Comparisons with Pavlovian/Classical conditioning.
o In Pavlovian conditioning, the US or reinforcer (the food, a
reward) is contingent upon the presentation of the CS, the tone.
But in instrumental conditioning the reinforce is contingent on
the animal’s response
o Conditioned Responses in Pavlovian Conditioning (salivating to
the tone alone) usually have a zero chance of occurring initially,
before conditioning. But in instrumental conditioning responses
usually have some initial probility of occurring
2. Conditions for Learning
Contingency
Temporal Relationships
Similarity and Spatial Contiguity of Events
Prior Learning
Extinction
Biological Significance of Events; Constraints on Learning
Contingency/Predictiveness: Temporal contiguity is not enough
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Pavlov’s belief that contiguity was enough
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Rescorla’s work
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Further Evidence
o blocking. the ability of the first CS to reduce the
informativeness of the second CS
- Leon Kamin’s fear conditioning study
- Related topic: Rescorla-Wagner Theory
Temporal Relationships: Sometimes Contiguity IS important!
Similarity and Spatial Contiguity of Events
- Rescorla’s study
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Related Topic: stimulus generalization.
o The readiness of an organism to respond to altered stimuli is
called stimulus generalization.
Prior Learning
- Example: blocking
- Example: latent inhibition.
Extinction
Extinction: removing the US (e.g., food) and observing the CR (e.g., salivation
response to bell) frequency wane
Are associations lost after extinction?
- Savings: speeding up of relearning compared to initial learning
Biological Significance of Events
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The relevance or belongingness of stimuli or of a stimulus and a
response is now recognized as being generally important in
conditioning.
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Adaptive specialization
Example: Pigeons more readily use visual than auditory stimuli as
signals for food.
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Example: conditioned taste aversion.
- Other examples of biological significance and learning:
3. The Evolution of Learning
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Learning allows individuals to adjust their behavior to the local state of
the world
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Learning is costly too.
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The benefits to learning are high