Introduction to Psychology

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Introduction to Psychology

• Learning

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Learning

• Learning refers to an enduring change in the way
  an organism responds based on its experience
• Distinct from
• Drug effects (caffeine-induced jitters are not
  learning)
• Fatigue or illness
• Three assumptions of learning theories
• Responses are learned rather than innate
• Learning is adaptive
• Our experiments can uncover the laws of learning
• These laws will apply to animals and to humans

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Classical Conditioning

• The Russian physiologist Pavlov noted that
  reflexive salivation in dogs could be elicited by
  stimuli associated with feeding
• Reflex Response that is reliably elicited by a
  stimulus
• Food elicits salivation
• Air puff elicits eye blink
• Reflexive stimulus and response are unconditioned
• Neutral stimulus is referred to as the
  conditioned stimulus (CS)
• CS is paired with the UCS over many trials
• Eventually comes to elicit a conditioned response
  (CR resembles the UCR)

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Pavlovs Experiment
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Acquisition and Extinction

• Acquisition of classical conditioning
• Repeated pairings of CS and UCS
• Extinction Refers to the weakening of
  conditioning evident when the CS is presented
  repeatedly without the UCS
• Spontaneous recovery Refers to the reemergence
  of a previously extinguished CR

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Stimulus Generalization and Discrimination

• Stimulus generalization occurs when an organism
  that has learned a response to a specific
  stimulus responds in the same way to new stimuli
  that are similar to the original stimulus.
• Stimulus discrimination occurs when an organism
  that has learned a response to a specific
  stimulus does not respond in the same way to new
  stimuli that are similar to the original stimulus.

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Classical Conditioning Issues

• Temporal order of presentation of CS and UCS is
  important
• Best conditioning CS precedes UCS (forward)
• Worst conditioning UCS precedes CS (backward)

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Conditioned Taste Aversion

• If a flavor is followed by an illness experience,
  animals will avoid the flavor in the future
• CS UCS ----------gt UCR
• Taste Toxic event Nausea
• CS -----gt CR
• Flavor Nausea

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Positive Reinforcement

• Reinforcer An environmental stimulus that
  occurs after the response and increases the
  likelihood that the response will occur in the
  future
• Positive reinforcement Process by which
  presentation of a stimulus after a response makes
  the response more likely to occur in the future
• Negative reinforcement Termination of an
  aversive event makes a behavior more likely to
  occur in the future

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Issues in Negative Reinforcement

• Negative reinforcement involves a situation in
  which a response that terminates an aversive
  stimulus will strengthen that response
• Taking an aspirin will reduce the headache and
  strengthen the behavior of aspirin-taking
  (sometimes referred to as escape-learning)
• Avoidance learning A response prevents a
  potentially aversive event from occurring
• Child cleans his room to avoid parental nagging

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Punishment

• Punishment decreases the likelihood that a
  response will occur
• Examples of punishing situations
• Presentation of an aversive stimulus (Positive)
• Parent spanks a child for taking candy...
• Owner swats a dog who has chewed her slippers...
• Removal of a reward (Negative)
• Teenager who stays out past curfew is not allowe
  d to drive the family car for 2 weeks...
• Husband who forgets anniversary sleeps on couch
  for a week...

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Difficulties in Punishment

• Learner may not understand which operant behavior
  is being punished
• Learner may come to fear the teacher, rather than
  learn an association between the action and
  punishment (then avoids the teacher)
• Punishment may not undo existing rewards for a
  behavior
• Using punishment when the teacher is angry
• Punitive aggression may lead to future aggression

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Schedules of Reinforcement

• Continuous reinforcement Reinforcer is obtained
  for every response
• Intermittent schedules Reinforcer is not
  obtained for every response
• Ratio Schedules
• Fixed Ratio Every Nth response
• Variable Ratio The average is every Nth
  response
• Interval Schedules
• Fixed Interval After the elapse of N minutes
• Variable Interval On average, after N minutes

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Impact of Schedules of Reinforcement on Behavior
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Observational Learning

• Social Learning Theory (Bandura)
• Modeling
• Vicarious learning
• Acquisition vs. Performance