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Operant Conditioning II
         Review of schedules
•   FI
•   VI
•   FR
•   VR
• Reinforcement schedule and extinction
• Partial reinforcement extinction effect –
  (PREE)
  – Persistent responding during extinction after
    partial reinforcement training.
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                                 CR-SAL
                            10   PR-SAL



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                              T1
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                             EX           Sessions
• Paradoxical
• Behavioral persistence
• PREE in everyday life
  – Addiction
  – Slot machines
• Why does PREE occur?
  – Discrimination hypothesis
  – Role of emotion: frustration theory
• Primary frustration
• Anticipatory frustration
• Counterconditioning
 Other paradoxical reward effects
• Magnitude of Reinforcement Extinction Effect
  – MREE
  – Conditioning with large reward extinguishes faster
    than conditioning with small reward
• The Frustration Effect: greater responding
  after nonreward than after reward.
           Other “emotional behavior”
• Extinction-induced frustration
• Effects of frustration
  – Aggression: Azrin pigeon studies
  – Enhance behavior
     • Adjunctive behaviors – example: schedule-induced
       polydipsia
     • the frustration effect:
     • Extinction spike – increased responding in first
       extinction session
  – Terminate behavior
     • E.g., negative contrast
             Contrast effects
• Successive Negative Contrast (SNC)
  – Model of anxiety
 Other things that affect operant conditioning

• Free reinforcers -degraded contingency effect
  – Reduces the level of instrumental behavior
           Theories of Reinforcement

• Two questions:
  – 1. What makes something effective as a
    reinforcer?
  – 2. How does a reinforcer produce an increase in
    the probability of the reinforced response?
• Reinforcers as stimuli
• The Law of Effect
  – Only answers question 2.
• Drive Reduction Theory
  – Clark Hull
  – Relies on homeostasis
  – Drive state exists
     • E.g., hunger, thirst
  – Reinforcer works by reducing drive state
  – Importance of motivation
  – Does this always work?
• Incentive motivation
  – Reinforcers are effective because they increase
    drive
  – They are arousing
• Brain Stimulation
  – Something is reinforcing because it activates a
    certain part of the brain – the nucleus accumbens
    and other areas.
  – Direct stimulation studies
  – No deprivation is needed, satiation does not
    occur.
  – Rewards typically generate activity in the Nacc no
    matter the type of reward.
     • Even pictures of attractive people
                Reinforcers as Responses
•   Other theories conceptualize a reinforcer as a
    response
    –   Food is not a reinforcer, the act of eating is.
•   David Premack
•   What makes eating a reinforcing response?
    –   Not a drive state. The existence of two responses that
        differ in their likelihood of occurrence when the
        organism is given free access to both activities.
•   Behaviors can be ranked to preference
•   Premack principle – The opportunity to perform
    the higher probability response will serve as a
    reinforcer for the lower probability response.
• Problem: preferred behavior changes over
  time.
  – Can even be transient
  – “what we obtain too cheaply we esteem too
    lightly”
• Premack only answers question 1
• Behavioral regulation theory
   – Also responses as reinforcers
   – Idea of response deprivation – some responses are free to
     occur, some are restricted
   – Conditioning situation puts a limitation on certain
     responses
   – behavioral bliss point – form of homeostasis. How an
     organism distributes its activities normally
      • Depends on the person
   – Instrumental response allows us to obtain behavioral bliss
     point
   – Answers both questions 1 and 2
            Does Punishment Work?
• Skinner said no.
  – Nearly every experiment he did that used
    punishment found that it did not reliably decrease
    behavior
• Subsequent research: It can work. Must be
  done in a certain way.
• Must be immediate
• Must be consistent
• Must be severe initially (Immunization to
  punishment)
           Side-effects of Punishment

• Increased aggression
  – Studies with animals
  – Person learns that aggression is a way to cope
    with problems
     • abusive parents come from abusive homes
• Generalization of fear
  – Can generalize to desired behaviors
  – Ex. Overbearing parents, fear of school, learned
    helplessness
• Punished behavior is not forgotten, it's
  suppressed
  – behavior returns when punishment is no longer
    eminent
• Punishment does not necessarily guide toward
  desired behavior
  – Combination of punishment and reward can be
    more effective than punishment alone

				
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