🥯Learning Unit 3 – Operant Conditioning – Thorndike and Skinner

Key Concepts and Definitions

• Operant conditioning a learning process in which the strength of a behavior is modified by reinforcement or punishment
• Reinforcement increases the likelihood of a behavior being repeated in the future
  • Positive reinforcement involves adding a desirable stimulus to increase the probability of a behavior
  • Negative reinforcement involves removing an aversive stimulus to increase the probability of a behavior
• Punishment decreases the likelihood of a behavior being repeated in the future
  • Positive punishment involves adding an aversive stimulus to decrease the probability of a behavior
  • Negative punishment involves removing a desirable stimulus to decrease the probability of a behavior
• Discriminative stimulus a cue that signals the availability of reinforcement or punishment for a particular behavior
• Shaping gradually reinforcing successive approximations of a desired behavior until the target behavior is achieved

Historical Context

• Edward Thorndike (1874-1949) an American psychologist who studied animal learning and developed the Law of Effect
• B.F. Skinner (1904-1990) an American psychologist who built upon Thorndike's work and developed the principles of operant conditioning
• Thorndike's experiments with cats in puzzle boxes (1898) laid the foundation for the study of instrumental learning
• Skinner's experiments with rats and pigeons in operant conditioning chambers (1930s-1950s) expanded the understanding of reinforcement and punishment
• The rise of behaviorism in the early 20th century emphasized observable behavior and environmental influences on learning
  • Behaviorists rejected the study of mental processes and focused on measurable responses to stimuli
  • Operant conditioning became a dominant learning theory during this period

Thorndike's Law of Effect

• States that behaviors followed by satisfying consequences are more likely to be repeated, while behaviors followed by unpleasant consequences are less likely to be repeated
• Based on Thorndike's experiments with cats in puzzle boxes
  • Cats learned to escape the box by trial and error, gradually reducing the time needed to perform the correct response
  • Thorndike concluded that successful responses were "stamped in" by the satisfying consequence of escape
• The Law of Effect introduced the concept of reinforcement as a key factor in learning
• Thorndike also proposed the Law of Exercise, which states that the strength of a behavior increases with practice and decreases with disuse
• The Law of Effect laid the groundwork for Skinner's operant conditioning principles

Skinner's Operant Conditioning

• Focuses on the relationship between behavior and its consequences
• Skinner introduced the concept of the three-term contingency: discriminative stimulus, response, and reinforcing stimulus
  • The discriminative stimulus sets the occasion for the response
  • The response is the behavior that is reinforced or punished
  • The reinforcing stimulus increases the likelihood of the response occurring again in the future
• Skinner developed the operant conditioning chamber (Skinner box) to study the effects of reinforcement and punishment on behavior
  • The chamber typically contains a lever or key that an animal can press to receive a reinforcer (food pellet) or avoid a punisher (electric shock)
  • The animal's responses are recorded and analyzed to determine the strength and frequency of the behavior
• Skinner emphasized the role of schedules of reinforcement in shaping and maintaining behavior
  • Continuous reinforcement provides reinforcement after every desired response
  • Partial (intermittent) reinforcement provides reinforcement after some, but not all, desired responses
    • Fixed-ratio, variable-ratio, fixed-interval, and variable-interval schedules are examples of partial reinforcement

Types of Reinforcement and Punishment

• Positive reinforcement strengthens a behavior by providing a desirable stimulus after the behavior occurs
  • Examples: praise, treats, money, or privileges
  • Increases the likelihood of the behavior being repeated in the future
• Negative reinforcement strengthens a behavior by removing an aversive stimulus after the behavior occurs
  • Examples: taking painkillers to relieve a headache, using an umbrella to avoid getting wet in the rain
  • Increases the likelihood of the behavior being repeated in the future
• Positive punishment weakens a behavior by providing an aversive stimulus after the behavior occurs
  • Examples: scolding, fines, or electric shocks
  • Decreases the likelihood of the behavior being repeated in the future
• Negative punishment weakens a behavior by removing a desirable stimulus after the behavior occurs
  • Examples: time-outs, losing privileges, or having a toy taken away
  • Decreases the likelihood of the behavior being repeated in the future
• Primary reinforcers are inherently rewarding stimuli that satisfy biological needs (food, water, shelter)
• Secondary (conditioned) reinforcers acquire their reinforcing properties through association with primary reinforcers (money, grades, praise)

Experimental Methods and Studies

• Skinner's operant conditioning chamber (Skinner box) a controlled environment for studying the effects of reinforcement and punishment on behavior
  • The chamber allows researchers to precisely control the delivery of reinforcers and punishers
  • Responses (lever presses, key pecks) are automatically recorded and analyzed
• Shaping a technique used to teach new behaviors by reinforcing successive approximations of the target behavior
  • Example: training a rat to press a lever by initially reinforcing any movement toward the lever, then only reinforcing touches, and finally only reinforcing complete presses
• Chaining a technique used to teach complex behaviors by linking together a series of simpler behaviors, each serving as a reinforcer for the previous behavior
  • Example: training a dolphin to perform a series of tricks in a specific order
• Discrimination training teaching an animal to respond to one stimulus (S+) and not to another (S-)
  • Example: training a pigeon to peck a red key for food reinforcement, but not a green key
• Generalization the tendency for a learned response to occur in the presence of stimuli similar to the original discriminative stimulus
  • Example: a dog trained to sit on command in the living room may also sit on command in the backyard

Real-World Applications

• Behavior modification techniques based on operant conditioning principles are used to change problematic behaviors and teach new skills
  • Examples: token economies in classrooms, habit reversal training for tics, and applied behavior analysis for autism
• Positive reinforcement is often used in animal training (dog obedience, marine mammal shows) to teach desired behaviors
• Negative reinforcement is a common factor in the development and maintenance of anxiety disorders and avoidance behaviors
  • Example: a person with social anxiety may avoid social situations to reduce feelings of discomfort, negatively reinforcing the avoidance behavior
• Schedules of reinforcement are used in gaming and social media to encourage continued engagement and maintain user behavior
  • Example: variable-ratio reinforcement in slot machines and "likes" on social media posts
• Operant conditioning principles are applied in organizational behavior management to improve employee performance and safety
  • Example: using feedback and incentives to increase the use of personal protective equipment in a factory

Criticisms and Limitations

• Operant conditioning focuses primarily on observable behavior and may neglect the role of cognitive processes in learning
• The emphasis on external reinforcement may undermine intrinsic motivation and creativity
  • Example: providing rewards for reading may decrease a child's natural interest in books
• Operant conditioning principles may not fully explain complex human behaviors and decision-making processes
• Ethical concerns arise when using punishment, particularly positive punishment, as it can have unintended consequences and may not address the underlying causes of behavior
• Individual differences in sensitivity to reinforcement and punishment may limit the generalizability of findings from animal studies to humans
• The artificial nature of laboratory settings may not accurately reflect real-world learning situations
• Operant conditioning does not account for the influence of social and cultural factors on behavior
• The theory may oversimplify the learning process and fail to consider the role of genetics, emotions, and other internal factors in shaping behavior