Instrumental Conditioning

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Instrumental Conditioning

• A procedure in which learning occurs with respect
  to a 3-term relationship of stimulus, response,
  and reinforcer. This procedure was first
  systematically studied by Edward Thorndike and
  was developed further by B.F. Skinner.

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Classical vs. Instrumental Conditioning

• Noncontingent vs. contingent outcomes
• Classical Conditioning is Noncontingent
• Instrumental Conditioning is Contingent

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Classical vs. Instrumental Conditioning

• Pigeon key-pecking
• Autoshaping A key light is followed by food
  delivery, regardless of what the pigeon does
• Operant keypecking A key light is followed by
  food delivery, only if the pigeon pecks the key

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Instrumental Conditioning Examples

• Lever-pressing by rats
• Invented by Skinner
• Key-pecking by pigeons
• Invented by Skinner
• Maze learning
• T-maze
• radial maze
• water maze
• Shuttle box

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Instrumental Conditioning Terminology

• Discriminative Stimulus
• (SD or S? )
• Operant response
• Reinforcement
• - Positive reinforcement
• - Negative reinformcement
• Reinforcement Schedule
• Shaping

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Functional Definitions

• Stimulus
• A stimulus is an event in the presence of which a
  reinforced response occurs with a changed
  frequency
• Response
• A response is a behavior which changes in
  frequency as a result of the presentation of
  reinforcement in the presence of a stimulus
• Reinforcement
• A reinforcer is an event which leads to a change
  in frequency of a response in the presence of a
  stimulus

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An ExampleChuckie

• Chuckie was a nonverbal, nonsocial child who sat
  by himself and rocked for hours. Ivar Lovaas
  used behavior modification procedures to teach
  Chuckie to speak, initially reinforcing his
  responses with food
• Stimulus picture of cat
• Response cat
• Reinforcer M M

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Reinforcement Schedules

• Interval
• Time based
• Ratio
• Response based
• Concurrent
• Two schedules, two responses
• Chain
• Successive schedules
• DRL
• Differential reinforcement of low rates

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Response-Reinforcer Associations

• Lever press gt sucrose
• Chain pull gt rat chow
• Sate on sucrose
• What does rat do?
• It pulls the chain
• Sate on rat chow
• What does rat do?
• It presses the lever

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Generalization / Discrimination

• Spontaneous generalization
• Effects of discrimination training
• Intradimensional training
• Interdimensional training
• Extradimensional training