Why do consequences influence behavior

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Why do consequences influence behavior?

• Because our behavior is rational.
• Cost - Benefit analysis
• Take into account - value and probability.
• Example
• Food - 10
• Shock - -25
• Exercise - 1

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• Bar
• .67 x 10 .33 x -25 -1.55
• Wheel
• 1 x 1.0 1.0
• Nothing
• .10 x 10 .90 x 0 1.0
• Alternate Wheel and Nothing

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How do we learn contingency?

• Learning does not depend on reinforcement.
• We learn by paying attention to association.
• Experiment
• G. Loftus (1972)
• Asked subjects to learn pictures
• More pictures - more reinforcement

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• Pictures were presented in pairs.
• Each picture had different reinforcement value
• e.g. 1 - 9
• Expectation
• More reinforcing value - more learning

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• Results
• more reinforcing value - more learning
• but, the amount of time they viewed the pictures
  differed depending on reinforcing value.
• Equated the amount of viewing time - no
  difference in learning
• Conclusion
• Attention determines learning

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What are consequences?

• Positive Negative
• Reinforcement
• Punishment

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Aversive Control What are the variables that
affect punishment?

• 1. Delay
• 2. Severity
• 3. Consistency
• 4. Noncontingent punishment
• 5. Available alternative response
• 6. Response produced by punishing stimulus

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But..

• Dont use punishment was a primary control
  method.
• A number of problems
• General inhibiting effect
• Become angry at the person and motivated to
  deceive
• Lie to get even and avoid future punishment
• Effect doesnt last long (Skinner, 1938)

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Negative reinforcement

• Another form of aversive control.
• Avoidance conditioning.
• E.g., Shuttle box
• Interesting - Very difficult to extinguish
• Two ways of extinguishing
• Learn a response does not lead to escape.
• Learn no response does not lead to shock.

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Positive Reinforcement

• Big Question
• What makes reinforcer reinforcing?
• Big Answer
• Dont know
• A number of theories

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Drive reduction theory

• Clark Hull
• We have a number of needs.
• How do we know when to fulfill these needs?
• Sense the level of drive
• Drive internal energy that forces you to
  respond.

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• How do you know you made a right response?
• You sense - reduction in drive
• Reinforcer - A stimulus that reduces drive.

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Problems

• Some reinforcers do not reduce drive.
• Saccharin (Sheffield et al., 1959)
• Looking out the window (Butler, 1953)
• Some reinforcers increase drive
• Copulation (Sheffiled et al., 1951)

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Premack theory

• New idea - it is not the stimulus that
  reinforces.
• Rather it is a response.
• What kind?
• More probable response
• e.g., Studying Playing
• Playing reinforces studying because it is more
  probable

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Premack

• Gave 1 graders free access to
• Pinball machine and Candy dispenser
• Some spent more time - pinball.
• Others spent more time - candy dispenser.
• Contingency
• Need to spend more time with less preferred
  activity in order to access to more preferred one.

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• They spent more and more time with less preferred
  activity because it was reinforced with preferred
  activity.
• Reinforcer - more probable activity

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Weisman Premack (1966)

• Two activities - drinking and running
• Water deprived rats - drinking
• Water non-deprived rats - running
• Introduced contingency
• 15 licks requires 5 sec of running
• Water deprived rats - reduced licking
• Water non-deprived rats - increased licking

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Problems

• Less probable response reinforces more probable
  response.
• Timberlake and Allison (1974)
• Sweeter solution - Less sweeter solution
• Rats prefer sweeter solution
• So, if the contingency is 11
• Increase licking of less sweet solution to get
  access to sweeter solution

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• Change contingency to 101
• They usually dont drink that much sweeter
  solution.
• So, they cannot get access to less sweet solution
  as much as they like.
• Consequence - they increase licking sweeter
  solution to get access to less sweeter solution..
• Sweeter solution Less sweet solution

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Equilibrium theory

• An activity becomes reinforcing when you cannot
  engage in that activity at a normal level.
• Every activity has a baseline.
• Food
• if you cannot eat a normal level, you do whatever
  to return it to the normal level.
• Food becomes reinforcing, increase other activity.

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Behavioral Allocation

• Two activities A and B.
• Normal - 150 As and 50 Bs (3 1).
• Blisspoint
• To do one A, have to do one B (1 1).
• How many time, you do A?
• 50? 100? 150?
• A reinforced B and B punished A

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Neural basis of reinforcement

• Stimulation to hypothalamus can serve as a
  reinforcer (Olds and Milner, 1954).
• No obvious biological function.
• Contradicts drive reduction theory.