PSY 402

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PSY 402

• Theories of Learning
• Chapter 9 Motivation

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Hulls Response

• Spence modified Hulls drive theory to include
  findings of incentive motivation.
• K was added to account for incentive.
• Behavior strength D x H x K
• Drive is innate and internal, incentive is
  learned and external.
• Drive pushes behavior, incentive pulls it.

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Fractional Anticipatory Goal Reactions

• The idea of a motive seemed mentalistic how can
  a behavioristic theory explain expectations and
  goals?
• rG-sG mechanism -- Intermediate states between
  the initial behavior and the goal are chained
  together by associations (classical
  conditioning).
• RG goal reaction or response (capital R)
• rG association of goal box with goal reaction
  (small r)
• sG similarity between start and goal box evoked
  rG salivation, which becomes a stimulus
  motivating response

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Frustration

• Amsel extended the idea of rG-sG mechanisms to
  negative contrast (explained by the mentalistic
  concept of frustration).
• Expectation of a big reward (RG) but receipt of a
  small reward results in frustration (RF).
• The size of RF is the discrepancy between
  previous rewards and the current reward size.
• rF also becomes generalized to the goal box and
  start box to demotivate (reduce responding).

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Paradoxical Reward Effects

• In some situations, reward seems to weaken, not
  strengthen responding.
• Negative contrast is one example a perfectly
  good reward fails to motivate responding.
• Magnitude of reinforcement effect --
  reinforcement with a large reward leads to faster
  extinction than reinforcement with a small one.
• Overlearning extinction effect many rewarded
  trials extinguish faster than a few rewarded
  trials.

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Effects on Intrinsic Motivation

• Rewarding a behavior that was previously
  performed for intrinsic reasons (internally
  motivated) leads to reduced behavior.
• Preschoolers expecting reward drew less.
• Punished by reward phenomenon some suggest
  that rewarding creative activity may hurt it.
• Reward effects are relative and complex (affected
  by many factors).

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Skilled Use of Reward

• Performance decreases in situations where
• Rewards were tangible (money)
• Announced ahead of time
• Given in a way that was not dependent on
  performance.
• Reward is perceived as a way to manipulate or
  control someone.
• Performance increases when verbal praise is
  given, when reward is unexpected, relevant.

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Persistence of Behavior

• Partial reinforcement extinction effect (PREE)
  behavior is more resistant to extinction when it
  is reinforcement intermittently.
• Continuous reinforcement acquired faster and
  extinguished faster.
• Partial reinforcement (50, VR-2) acquired
  slower and extinguished slower.
• Persistence generalizes to other tasks learned
  industriousness.

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Theories about PREE

• Amsels frustration theory -- animals learn to
  respond in the presence of frustration.
• Frustration attaches to the stimulus (sF) after
  an unrewarded trial, then responding to it is
  rewarded.
• Capaldis sequential theory the rat has a
  memory of responding after a non-reinforced
  trial.
• It responds because the stimulus is familiar.

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New Understanding of Extinction

• Extinction involves new learning that is
  dependent on context.
• Research on PREE suggests also that
• Extinction occurs when generalization from
  acquisition trials stops (generalization
  decrement)
• Frustration occurs and reduces motivation when an
  expected reward does not occur, but is not needed
  to explain PREE.

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Problems with rG-sG

• If classically conditioned associations motivate
  behavior, they should correlate with responding,
  but they dont.
• Concurrent measurement studies showed little
  correlation between salivation and responding
  rewarded by food.
• In studies of shock avoidance, fear (rE) showed
  little correlation with vigor of avoidance.
• Central states not peripheral should be measured.

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Transfer of Control

• Increasing or decreasing the intensity of an
  internal state (expectancy) should affect
  behavior.
• Pavlovian-Instrumental Transfer.
• An instrumental behavior and a CS are both
  learned separately.
• When paired with each other, behavior should
  increase.
• Dogs in shuttle box showed this effect.

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Effects of Pavlovian CSs

• Some of the effects of Pavlovian inhibitors on
  instrumental responding occur because of evoked
  fear.
• Rat freezing due to fear interferes with
  avoidance.
• Excitatory Pavlovian CSs can activate an entire
  system, not just a specific response.
• In other contexts, the effect of the CS is
  specific to the type of reward (food vs water).
• The explanation for this is unclear.

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Practical Applications

• Classical conditioning (CSs) are always present
  and affect instrumental behavior.
• Obsessive checking behavior is worse when anxiety
  is heightened by a CS, better when less fear is
  evoked.
• CSs associated with a drug increase the
  motivation for drug-taking behavior.
• CSs evoke a system of responses one of which may
  be instrumental behavior.

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Opponent-Process Theory

• Emotional after-reaction an emotional stimulus
  creates an initial response that is followed by
  adaptation, then opposite response.
• With repeated exposure to the stimulus, the
  pattern changes.
• The primary affective response (a-process)
  habituates.
• The after-reaction (b-process) strengthens

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Imprinting

• Baby ducks initially respond only to moving
  stimuli, but with repeated exposure will be
  comforted by a stationary stimulus.
• They follow it around due to sign tracking.
• The imprinted stimulus (train) can calm an upset
  duck but causes distress when removed, even if
  the duck is already calm.
• The distress is the b-process in attachment.

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Effects of Repeated Exposure

• Ducks become more attached to an imprinted
  stimulus after repeated exposures.
• Exposures must be massed (spaced close together
  in time).
• A single long exposure produces a
  distress-calling after-reaction.
• This is contrary to other classical conditioning
  situations, where massed exposure is worse.

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Drug Addictions

• Withdrawal symptoms seem to be an
  opponent-process elicited by a CS associated with
  the drug (S).
• The CR is the b-process and it offsets the bodys
  response to the drug itself.
• The opponent process appears to be learned, not
  innate.
• It is problematic for the learning explanation
  that the b-process increases with massed exposure.