What do reinforcers and punishers do?

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What do reinforcers and punishers do?

• Learning provides the knowledge, and reinforcers
  provide the goals to cause the organism to act on
  that knowledge (Anderson, 2000, p.119).

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Rational behavior
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Rationality and optimality

• Individuals choose rationally within the limits
  of their knowledge.
• Choices that are less than optimal may result
  from biological or learned preparedness that is
  inappropriate for a particular situation
  Choosing sweet foods over nutritious foods, for
  example.

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Rational analysis

• Individuals combine the probabilities of
  particular outcomes with the value of those
  outcomes to determine the best course of action.
  For example
• If p(food) is high and the value of food is also
  high, respond to get food.
• If p(food) combined with value of food is lower
  than p(warmth) combined with value of warmth,
  respond to get warmth.
• If the products are equal, alternate.

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Comparing rational analysis and Hull

• Hull
• E (H x D x K) - I (Recall that H is a product
  of reinforcement history)
• Rational analysis
• E H x (DxK) (that is, p(reward) x value of
  reward
• If two responses are mutually exclusive, both
  Hull and rational analysis predict the same
  choice behavior.

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But what if the same response produces good and
bad consequences?

• If a bar press produces food 67 of the time and
  shock 33, what will the subject do?
• It depends on the value of the consequence.
• The likelihood of a response is the sum of the
  products of p(reward) multiplied by value
• E (.67 x 10) (.33 x -25) -1.55
• The bar press will not happen until the value of
  food increases sufficiently.

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Does reward affect learning?

• Rational analysis suggests that reward only
  influences choice, not learning probabilities.
• The surprising conclusion Learning does not
  depend on reward.

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Human research Within groups

• Within-group studies show that differential
  reward does affect learning (eg. Harley, 1965).

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9
Human research Between groups

• Between-group studies show that differential
  reward does not affect learning.

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10
Can contingencies of reward ever affect learning?

• Loftus, 1972 When participants know about
  differential reward, it affects learning.
• More time is spent learning material (more
  fixations) which promises a higher reward.
• Thus, reinforcement can affect attention and
  effort in learning, if and only if the learner
  knows about the different consequences while
  learning.
• What do review sheets do to students?

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An interesting study to do

• Begin a study session with no knowledge of
  differential reinforcement
• At some point in the session, inform participants
  of differential reinforcement
• Eg., tell them which items are more likely to be
  on the exam.
• Measure study time (fixation time and/or
  rehearsal time) for the two sets of items before
  and after the information is given.

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Differential reward effects

• Differential reward will affect learning only if
  it enables the learner to allocate attention
  differentially.
• Different levels of reward have no direct effect
  on learning. You will learn just as much for a
  dime as for a dollar, if you do not know the
  difference in reward.

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Another angle on differential reward

• Capuchin monkey fairness protests (deWaal
  Brosnan, 2003)
• Monkeys trained with different foods as rewards
  for the work of exchanging differently valued
  tokens.
• Eg, a blue token could be exchanged for a piece
  of cucumber (low value), a red token for a grape
  (high value).
• They readily learned the exchange rules.

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But then

• deWaal Brosnan put the monkeys in pairs, so
  they could observe each others exchanges.
• The researchers began giving one monkey a better
  reward than was justified by the token offered,
  while rewarding the other monkey by the exchange
  rules.
• The exchange rules monkeys stopped playing the
  game, or refused the lesser reward.
• The effect was greater if one monkey was given
  handouts.
• The monkey given the greater reward never
  protested.

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A naive view of contingency consequences
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A better view of contingency
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Application question

• What is happening when parents ground a child?
• Positive reinforcement?
• Omission training?
• Punishment?
• Negative reinforcement?

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Applying reinforcement

• Behavior modification 1 Contingency management
• The classroom Catch them being good
• Hall, Lund Jackson (1968) Robbie, 6/7 classes
• But it doesnt always work
• Difficult to be consistent
• Different strokes for different folks
• Systematic reinforcement The token economy
• Immediate secondary reinforcement
• Enhanced subjective reward value through choice
• Extra reinforcement for group meeting standards
  recruits peer pressure

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Maintaining behavior

• Non-reinforcement leads to extinction
• But the extinction effect is mitigated by
• Partial reinforcement
• Reinforcement in multiple settings
• Fading

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But is reinforcement all good?

• It uses bribery to play to human greed
• It undermines other motivators
• Less powerful reinforcersthe negative contrast
  effect
• Intrinsic motivation (Lepper, Greene Nisbett,
  1973)
• Internalized control and self-concept/ego ideal

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What factors influence whether reinforcement will
undermine behavior?

• High intrinsic motivation is more readily
  undermined
• Perceived coercion undermines behavior
• Ryan (1982)
• Brehms (1966) reactance theory
• Reinforcing task completion vs. task competence
  (Enzle Ross, 1978)

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What else can we do to minimize undermining?

• Use reinforcement for behaviors with low
  intrinsic motivation
• Use praise rather than material rewards
• Reward competence rather than compliance

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More methods to minimize undermining

• Match reinforcement to the optimal motivation
  level according to the Yerkes-Dodson law
• Use the minimum reinforcement necessary
• Start with social reinforcers
• Use behavioral contracts

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Aversive control of behavior

• Punishment
• Observational and correlational research vs.
  experimental research
• Punishment is not necessarily corporal.
• Avoidance
• How can the non-occurrence of a behavior be
  reinforced?

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Principles of punishment

• Severity or intensity Skinner (1938) and
  Thorndike vs. Boe Church (1967) and Bucher
  Lovaas (1968)
• Systematic desensitization (Azrin, Holz Hake,
  1963)
• Systematic sensitization
• Secondary punishment
• Immediacy vs delay (Solomon, Turner Lessac,
  1968)
• Delay has no effect on learning to suppress a
  response.
• Delay does reduce perseverance of response
  suppression.
• With humans, delay effects are found in a matter
  of seconds.

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More principles of punishment

• Consistency/high differential contingency FR1
  vs. FR1000 (Azrin et al., 1963)
• Child observation (Larzelere, Schneider, Larson,
  Pike (1996)
• Criminal activity (Brennan Mednick, 1994)
• Punishment inoculation by non-contingent
  application (gratuitous punishment That was for
  nothing. Dont try anything.)
• Reasoning or verbal explanation improves
  punishment effects, perhaps by assisting
  discrimination learning.

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Still more principles of punishment

• Since many inappropriate responses persist
  because they are being reinforced, punishment is
  more effective if alternate routes to the
  reinforcer are available.
• Poorly done punishment can produce suppression of
  desirable responses (CER), increased anger and
  aggression, lying as an avoidance behavior, and
  imitation of punishing with peers and weaker
  people.

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A punishment ideal

• Punishment works best when it signals
• non-availability of reward for the punished
  behavior, and
• availability of the desired reward if a different
  behavior is chosen.
• Can you think of examples of this approach?

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Other aversive approaches

• Response cost
• Randy and the smiley-face chart