Behavioral Psychology - Key Concepts in Extinction and Reinforcement

Spontaneous Recovery

  • Definition: Reappearance of an extinguished response following a rest period after extinction.
    • Example: A rat's behavior of lever pressing is extinguished. When it is placed back in the chamber the next day:
    • Behavior may be weaker than at the start of the extinction phase.
    • Behavior will extinguish more quickly if reinforcement continues to be withheld.
    • Eventually, spontaneous recovery may not occur, indicating that the behavior is essentially eliminated.

Factors Influencing Spontaneous Recovery

  • Skinner's (1950) Proposal: Spontaneous recovery may depend on discriminative stimuli (S) present at the start of a session.
    • Example:
    • An experimental rat experiences being taken from its home cage, weighed, and placed in an operant chamber, signaling availability of food.
    • If food is not received after repeated experiences, the rat stops the learned behavior.
    • Similar to a child learning to throw tantrums for candy in a supermarket, where entering serves as a signal for candy availability.

Introduction to Extinction

  • Extinction: The nonreinforcement of a previously reinforced response leads to a decrease in response strength.
    • Example:
    • Child learns to whine for candy:
      • Whining (R) → Candy (SR)
      • If whining does not produce candy anymore:
      • Whining (R) → No candy (-).
    • Result: Whining will eventually cease.

Common Mistakes with Extinction

  • Ensure that the withheld consequence is indeed the reinforcer maintaining the behavior.
  • Do not use the term extinction to refer to any decrease in behavior strength; remember there are multiple methods to weaken or eliminate behavior, such as:
    1. Stopping food delivery for pressing a lever.
    2. Applying a shock when pressing the lever.
    3. Providing free food beforehand to reduce hunger.
    4. Removing the lever from the chamber.

Side Effects of Extinction

  • Extinction Burst: Temporary increase in frequency and intensity of responding when extinction is first implemented, as the subject tries harder to obtain the reinforcer.
  • Increase in Variability: The subject attempts various behaviors to obtain the reinforcer.
  • Emotional Behavior: Often accompanied by frustration or aggression.
  • Resurgence: Reappearance of other previously effective behaviors to obtain reinforcement during extinction.
  • Depression: Characterized by very low levels of activity.

Resistance to Extinction

  • Definition: The extent to which responding continues after an extinction procedure is implemented.
  • Can vary from high to low resistance.

Factors Affecting Resistance to Extinction

  • Partial Reinforcement Effect: Behaviors maintained on an intermittent schedule extinguish more slowly than those on a continuous schedule.
  • History of Reinforcement: More reinforcers received leads to greater resistance to extinction.
  • Magnitude of the Reinforcer: Larger reinforcers often lead to greater resistance.
  • Degree of Deprivation: Higher deprivation levels result in greater resistance.
  • Previous Experience with Extinction: More experience leads to faster extinction.
  • Distinctive Signal for Extinction: Extinction happens faster with a specific stimulus signalling the onset.

Differential Reinforcement of Other Behaviors (DRO)

  • Definition: Reinforcement of any behavior other than the target behavior being extinguished.
  • More effective than simple extinction as it weakens the target behavior and reduces unwanted side effects of extinction.

Functional Communication Training

  • A variant of DRO aimed at reinforcing functional communication instead of misbehavior.
  • Assumes misbehavior often occurs to obtain a reinforcer.
  • Training individuals to communicate desires can reduce misbehavior.

Stimulus Control

  • Presence of a discriminative stimulus affects the probability of behavior.
  • Stimulus Generalization: Tendency for a response to occur in the presence of stimuli similar to the SD (discriminative stimulus).
  • Generalization Gradient: Measures response strength in the presence of stimuli similar to the SD.

Examples of Stimulus Control

  • Stopping at red traffic lights; proceeding at green lights.
  • Saying "You’re welcome" in response to "Thank you."
  • Standing facing the front in an elevator.
  • Pulling over when hearing an ambulance siren.
  • Reading phone notifications despite distractions.
  • Students stopping chatter when a professor begins lecturing.

Stimulus Discrimination

  • Definition: Greater likelihood of emitting an operant response in the presence of one stimulus over another.
  • Discrimination Training: Reinforcement occurs in the presence of SD and not S∆ (stimulus for extinction).
    • Example:
    • 2000-Hz Tone (SD): Lever press (R) → Food (SR).
    • 1200-Hz Tone (S∆): Lever press (R) → No Food (-).
    • Result: Lever pressing happens only with the SD.

Peak Shift Effect

  • After discrimination training, the peak of generalization often shifts from the SD to a stimulus further removed from S∆.
  • Possible explanations:
    • Responding occurs relative to values of stimuli (e.g., higher pitch preferred).
    • SD may acquire negative properties due to similarity to S∆.

Multiple Schedules

  • Definition: Two or more independent schedules are presented in sequence with distinctive SDs.
  • Example:
    • Red key: Key peck VI 30” → Food.
    • Green key: Key peck VI 60” → Food.
  • Different than a chained schedule where all components must be completed for reinforcement.