Lesson 4: Instrumental Conditioning
Unit 1: Introduction
• Instrumental Conditioning: The learning of a contingency between behaviour and
• Explicit training between voluntary behaviours and their consequences
Unit 1: Instrumental Conditioning
• Thorndike’s Experiment: measured time it took cat to learn to open door by pulling string
The Puzzle Box
• Frequency of random behaviours gradually decreased over time.
• Suggests that animals follow a simple stimulus-response type process with little credit for
The Law of Effect:
• Stamping In: behaviours like pulling the role were stamped in because they were followed by
the favourable consequence of access to food
Stamping Out: random behaviours such as turning in a circles
• Eventually, general process leads to refinement and the cat learns the contingency between the
specific behaviour of rope pulling and the specific consequence of food reward
The Law of Effect: behaviours with positive consequences are stamped in
• Those with negative consequences are stamped out
Unit 3: Types of Instrumental Conditioning
Presentation of a positive reinforcer
• Presentation of a negative reinforcer
• Removal of a negative reinforce Lesson 4: Instrumental Conditioning
• Removal of a positive reinforce
• Presentation of a positive reinforcer ----> reward training (Picture of dog receiving a treat, or
person putting money into vending machine).
• Presentation of a negative reinforcer ----> punishment
• Decrease in the behaviour being reinforced.
• Must consider ethics of experiencing fear or pain in the recipient
• Authority figure may become a signal for pain or distress; damage the relationship.
• Removal of a positive reinforce ----> omission training
• Version of omission training includes classic time-out
• Removal of a negative reinforcer ----> escape training
• Aconstant negative reinforcer being presented that the learner is motivated to have removed.
By performing a specific response, the negative reinforcer can be removed which leads to an
increase in that response behaviour.
• Proceeds best when the consequence immediately follows the response.
Unit 4:Acquisition and Shaping
Learning the contingency between a response and its consequence
• Graphing response (cumulative recorder)
Autoshaping: Lesson 4: Instrumental Conditioning
• Animal, etc. will learn contingency on its own if placed in the environment without help from
• Shaping by successive approximations: Complex behaviour can be organized into smaller
steps which gradually build up to the full response we hope to condition
• Each of these steps can be reinforced through rewards training
Unit 5: Generalization and Discrimination
The Discriminative Stimulus:
• Discriminative stimulus (SD or S+)
• Sdelta (S-) is a cue which indicates when the contingent relationship is not valid
• SD indicated when the resp