Lecture 17

Learning 2

1. Operant Conditioning
1. Behaviorism
2. Key Assumption
3. Mechanism Illustrated
2. Thorndike
1. Procedure
2. Explanation
3. Thorndike's Laws
4. Natural Selection and Instrumental Learning
3. Skinner
1. Biography
2. Skinner Box
3. Discriminative Stimulus
4. Reinforcers and Punishers
5. Reinforcement Schedules
6. Shaping

Overview

Operant conditioning (aka instrumental learning) involves the acquisition of habits that were once voluntary (not reflexive). This form of learning was first identified by an American psychologist, Edwin Thorndike. Thorndike put animals in a "puzzle box" and arbitrarily decided which response would allow the animal to escape. Over time, the animal gradually comes to exhibit the correct response and learns to escape. According to Thorndike, the learning is not cognitive, thoughtful, or deliberate. Instead, a mindless association forms between the puzzle box and the correct behavior, and the animal reflexively (habitually) exhibits the behavior when placed in the box. Drawing on Darwin's theory of natural selection, Thorndike formulated two laws of behavior to describe the process.

B. F. Skinner was an American psychologist with a flair for the dramatic. He devised a more sophisticated puzzle box to study learning (called the Skinner box) and identified several variables that influence the rate at which an animal acquires a habit.

Specifics

• Identify the three basic assumptions that characterize American behaviorism.
• Discuss the doctrine of mechanism and how it explains the behavior of lower animals and humans.
• Describe the procedure Thorndike used, define his two laws of behavior, and know how they are derived from Darwin's theory of natural selection.
• Define and distinguish the following terms, and be able to identify examples of each: punishment and reinforcement (both positive and negative), and shaping.
• Distinguish fixed vs. variable rates of reinforcement, and know which one promotes learning and which one makes learning most resistant to extinction.