Learning

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Chapter 6Learning
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Classical or Pavlovian Conditioning

• Ivan Pavlov
• 1849-1936
• Russian physician/ neurophysiologist
• Nobel Prize, 1904
• studied digestive secretions

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Classical or Pavlovian Conditioning

• Pavlovs device for recording salivation

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Pavlovs Apparatus for Studying Classical
Conditioning in Dogs
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Classical or Pavlovian Conditioning Respondent
Behavior

• Unconditioned Stimulus (UCS)
• stimulus that unconditionally- naturally and
  automatically - triggers a response
• Unconditioned Response (UCR)
• unlearned, naturally occurring response to the
  unconditioned stimulus
• salivation when food is in the mouth

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Classical Conditioning Respondent Behavior

• learning in which a neutral stimulus acquires the
  capacity to elicit a response after being paired
  with another stimulus that naturally elicits that
  response
• Unconditioned response (UCR) automatic response
  to a stimulus
• Unconditioned stimulus (UCS) naturally and
  automatically elicits a response
• Conditioned response (CR) learned response to a
  previously neutral stimulus
• Conditioned stimulus (CS) after repeated
  pairings with UCS, elicits the same response

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Classical or Pavlovian Conditioning Respondent
Behavior

• Conditioned Stimulus (CS)
• originally neutral stimulus that, after
  association with an unconditioned stimulus, comes
  to trigger a conditioned response
• Conditioned Response (CR)
• learned response to a previously neutral
  conditioned stimulus

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Pavlovs Classic Experiment
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Classical or Pavlovian Conditioning
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Classical Conditioning
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Classic Conditioning Allows Animals to Learn to
Predict Events

• Learning theorists once believed that the
  learning in classical conditioning is
  unintentional and automatic (classic
  behaviorism).
• Most contemporary learning theorists now believe
  classical conditioning involves quite a bit of
  mindfulness because, (through the conditioning
  process) humans and other animals are learning to
  reliably predict upcoming events.

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Classic Conditioning Allows Animals to Learn to
Predict Events

• Psychologists once believed that the key to
  acquiring a conditioned response was the sheer
  number of CS-UCS pairings.
• However, the order and timing of CS-UCS pairings
  is also very important because it provides
  valuable information about the upcoming
  occurrence of the unconditioned stimulus.

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Utility of classical responding Avoiding a
Predators Attack through Classical
ConditioningStep 1
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Avoiding a Predators Attack through Classical
ConditioningStep 2
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Avoiding a Predators Attack through Classical
ConditioningStep 3
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Stages in Classical (Pavlovian) Conditioning

• Acquisition
• the initial stage of learning, during which a
  response is established and gradually
  strengthened
• the phase associating a neutral stimulus with an
  unconditioned stimulus

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Stages in Classical (Pavlovian) Conditioning

• Extinction gradual weakening and disappearance
  of the conditioned response
• Spontaneous recovery reappearance of an
  extinguished response after a period of
  nonexposure to the conditioned stimulus

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After Acquisition, Other Stimuli Can Produce the
Conditioned Response

• Stimulus generalization tendency for a
  conditioned response to be elicited by stimuli
  similar to the conditioned stimulus

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Generalization
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After Acquisition, Other Stimuli Can Produce the
Conditioned Response

• Higher-order conditioning neutral stimulus
  becomes a conditioned stimulus after being paired
  with an existing conditioned stimulus

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Animals Differ in What Responses Can Be
Classically Conditioned

• Early learning theorists assumed that the
  principles of conditioning were similar across
  all species, but subsequent research indicates
  that this assumption is incorrect.
• Animals often differ in what responses can be
  conditioned.
• In some animals, some responses can be
  conditioned much more readily to certain stimuli
  than to others.
• An animals biology steers it toward certain
  kinds of conditioning.

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Taste aversion study by Garcia and Koelling

• Rats learned to avoid a light-noise combination
  when it was paired with electric shock, but not
  when it was followed by X rays that made them
  nauseous.
• In contrast, rats quickly learned to avoid
  flavored water when it was followed by X rays,
  but they did not readily acquire an aversion to
  this same water when it was followed by shock.
• It is also adaptive that in taste aversion,
  strong conditioning develops despite the long
  delay between the CS (the taste) and the UCS (the
  nausea).

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Biological Constraints on Taste Aversion in Rats
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Animals Differ in What Responses Can Be
Classically Conditioned

• Phobias exaggerated and irrational fears of
  objects or situations
• Such intense fear reactions often develop through
  classical conditioning.
• We can develop a phobia toward anything, but some
  objects (snakes) or situations elicit phobic
  reactions more easily than others.

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Nausea Conditioning among Cancer Patients
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Little Alberts Fear Conditioning
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Operant Conditioning

• B.F. Skinner (1904-1990)
• elaborated Thorndikes Law of Effect
• developed behavioral technology

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Operant Behavior Is Voluntary Directedby
Consequences

• Edward Thorndike s Law of Effect
• the relationship between behavior and its
  consequences
• So named because behavior becomes more or less
  likely based on the effect it has in producing
  desirable or undesirable consequences.

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Thorndikes Law of Effect

• Rewarded behavior is likely to recur
• E. L. Thorndike

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Operant Behavior Is Voluntary Directedby
Consequences

• B. F. Skinner made the law of effect the
  cornerstone for his influential theory of
  learning, called operant conditioning.
• According to Skinner, the organisms behavior is
  operating on the environment to achieve some
  desired goal.
• Operant conditioning learning in which behavior
  is strengthened if followed by reinforcement and
  weakened if followed by punishment

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Operant Conditioning

• Operant Chamber (Skinner Box)
• soundproof chamber with a bar or key that an
  animal can manipulate to obtain a food or water
  reinforcer
• contains a device to record responses

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Skinner Box
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Shaping Reinforces Closer Approximations to
Desired Behavior

• Shaping (or the method of successive
  approximations) teaching a new behavior by
  reinforcing closer and closer approximations to
  the desired behavior

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A Reinforcer Increases the Probability of the
Behavior It Follows

• The fundamental principle of behaviorism is that
  rewarded behavior is likely to be repeated.
• This is known as reinforcement in operant
  conditioning.
• It also states the positive side of Thorndikes
  Law of Effect.

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A Reinforcer Increases the Probability of the
Behavior It Follows

• Primary versus secondary reinforcers
• Primary reinforcers innately reinforcingsatisfy
  biological needs.
• Secondary reinforcers learned and become
  reinforcing when associated with a primary
  reinforcer

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A Reinforcer Increases the Probability of the
Behavior It Follows

• Positive and negative reinforcers
• Positive reinforcers strengthen a response by
  presenting a positive stimulus after a response
• Negative reinforcer strengthens a response by
  removing an aversive stimulus after a response

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Positive and Negative Reinforcement, Positive and
Negative Punishment
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Different Reinforcement Schedules Lead to
Different Learning and Performance Rates

• Continuous reinforcement leads to the fastest
  learning.
• The biggest problem with continuous reinforcement
  is that when it ends, extinction occurs rapidly.

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Different Reinforcement Schedules Lead to
Different Learning and Performance Rates

• Partial reinforcement has an important effect on
  your continued performance because being
  reinforced only once in a while keeps you
  responding vigorously for longer periods of time
  than does continuous reinforcement.

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Different Reinforcement Schedules Lead to
Different Learning and Performance Rates

• Fixed-interval schedules reinforce the first
  response after a fixed-time interval has elapsed
• Fixed-ratio schedules reinforce a response after
  a specified number of nonreinforced responses
• Variable-interval schedules reinforce the first
  response after a variable-time interval has
  elapsed
• Variable-ratio schedules reinforce a response
  after a variable number of nonreinforced responses

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Schedules of Reinforcement
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Accidental Reinforcement Can Cause Superstitious
Behavior

• Superstitious behavior learned because it
  happened to be followed by a reinforcer, even
  though this behavior was not the cause of the
  reinforcer.
• Skinner trained superstitious behavior in hungry
  pigeons.
• He reasoned that when reinforcement occurred, it
  would be paired with whatever response the
  pigeons had just performed.
• Instances of accidental reinforcement triggering
  superstitious behavior is common among people.

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Punishment Should Be Used Only under Certain
Circumstances

• Punishment The process by which a consequence
  decreases the probability of the behavior that it
  follows.

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Punishment Should Be Used Only under Certain
Circumstances

• To be effective in reducing unwanted behaviors
• The punishment must be prompt,
• It must be relatively strong, and
• It must be consistently applied.
• Alternative to punishment of undesirable
  behavior
• Allow undesirable actions to continue without
  either positive or negative consequences until
  they are extinguished

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Criticism of Operant Conditioning Theory is that
it Overlooks Genetic Predispositions

• Biological constraints on learning
• As with classical conditioning, an animals
  biology can restrict its capacity for operant
  conditioning.
• Species-specific behavior patterns can interfere
  with operant conditioning, a genetic constraint
  called instinctive drift.

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Criticism of Operant Conditioning Theory is that
it Overlooks Cognitive Processes

• Latent learning learning that occurs without
  apparent reinforcement and is not demonstrated
  until sufficient reinforcement is provided
• Learning can occur without any reinforcement,
  something that the theory of operant conditioning
  assumed was not possible.

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Latent Learning
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Operant Conditioning Theory Overlooks Cognitive
Processes

• Learned helplessness the passive resignation
  produced by repeated exposure to aversive events
  that cannot be avoided
• Here again, in contradiction to behaviorist
  theory, research demonstrated that mental
  processes play a significant role in learning.

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Applications of Operant Conditioning

• Structure and feedback in learning immediate
  reinforcement
• Defined performance goals and immediate
  reinforcement at work
• Parenting reward good behavior, ignore whining,
  time-out

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Observational Learning

• learning by observing and imitating the behavior
  of others
• The others whom we observe and imitate are called
  models.
• Observational learning helps children learn how
  to behave in their families and in their
  cultures.Yet, what about the learning that occurs
  without direct experience?

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Social Learning Theory-Albert Bandura

• Social learning theory says that people learn
  social behaviors mainly through observation and
  cognitive processing of information, rather than
  through direct experience.
• Learning the consequences of an action by
  observing its consequences for someone else is
  known as vicarious conditioning.

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Children Can Learn Aggressive Behavior through
Observation

• Bobo doll studies the first set of experiments
  demonstrating the power of observational learning
  in eliciting aggression.
• Research demonstrates that children are less
  likely to imitate the actions of punished
  aggressors.

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Children Can Learn Aggressive Behavior through
Observation

• Bandura believes children observe and learn
  aggression through many avenues, but the three
  principal ones are
• Families where adults use violence
• Communities where aggression is considered to be
  a sign of manhood, especially among males
• Media principally television and the movies

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Children Can Learn Aggressive Behavior through
Observation

• Research indicates that aggressive behavior in
  children is significantly reduced when they spend
  less time watching violent television shows and
  playing violent video games.