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									Chapter 6




Learning
Learning Defined

Learning refers to the change in a subject’s behavior to
  a given situation brought about by his repeated
  experiences in that situation, provided that the
  behavior change cannot be explained on the basis of
  native response tendencies, maturation, or temporary
  states of the subject (i.e. fatigue, drugs, etc.)
                             -T. Rocklin (1987)




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What is learning?

   Learning refers to a relatively durable change in
    behavior or knowledge that is due to experience
   Includes:
    –   Acquisition of knowledge and skills
    –   Personal habits (i.e. nailbiting)
    –   Emotional responses (i.e. fear of storms)
    –   Personal preferences (i.e. taste for tacos)
   Conditioning: involves learning associations between
    events that occur in an organism’s environment



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Classical conditioning

   Phobias are irrational fears of specific objects or
    situations; can be mild (common) or severe
   Q: How are phobias acquired?
   A: Through classical conditioning—type of learning
    in which a stimulus acquires the capacity to evoke a
    response that was originally evoked by another
    stimulus; sometimes called Pavlovian conditioning
    after Ivan Pavlov (first person to describe process)



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Pavlov’s Demonstration:
“Psychic Reflexes”

   Ivan Pavlov—Russian physiologist studying role of
    saliva in digestive processes of dogs
   Presented meat powder to dogs, then collected saliva
   Discovered that after a while dogs would start
    salivating before meat powder presented—
    responding to ticking sound made by device that
    presented the powder
   Pavlov called the response “psychic reflexes”
   Investigated further by presenting a tone prior to
    meat powder; dogs began responding to sound of
    tone alone
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Terminology and Procedures
   Unconditioned stimulus (UCS)—a stimulus that evokes an
    unconditioned response w/o previous conditioning (i.e. meat powder)
   Unconditioned response (UCR)—an unlearned reaction to an
    unconditioned stimulus that occurs w/o previous conditioning (i.e.
    salivating when meat powder presented)
   Conditioned stimulus (CS)—a previously neutral stimulus that has,
    through conditioning, acquired the capacity to evoke a conditioned
    response (i.e. tone)
   Conditioned response (CR)—a learned reaction to a conditioned
    stimulus that occurs because of previous conditioning (i.e. salivating in
    response to tone)
   Unconditioned response and conditioned response can be the same
    behavior, but in response to different stimuli
   A trial in classical conditioning consists of any presentation of a
    stimulus or pair of stimuli; psychologists study how many trials it takes
    to establish a particular conditioned bond



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Classical Conditioning in
Everyday Life
   Conditioned fears
     – Many phobias can be traced back to experiences involving classical
       conditioning (i.e. bridge phobia)
     – Everyday fears can also be products of classical conditioning (i.e. sound of
       dentist drill)
   Other conditioned emotional responses
     – Sometimes conditioned responses are positive (i.e. Beemans gum and
       smoking)
     – Advertisers pair products w/items that elicit pleasant emotions (i.e. attractive
       people, enjoyable surroundings)
     – http://www.sharkattackphotos.com/Jaws_Theme_Song.htm
   Conditioning and physiological responses
     – Classical conditioning can lead to immunosuppression (animal study)
     – Also shown to elicit allergic reactions and contribute to drug tolerance



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Play Excerpt: The Chaplin of the
Virgin
Saint Ildefonso used to scold me and punish me lots of times. He would sit
   me on the bare floor and make me eat with the cats of the monastery.
   These cats were such rascals that they took advantage of my
   penitence. They drove me mad stealing my choicest morsels. It did no
   good to chase them away. But I found a way of coping with the beasts
   in order to enjoy my meals when I was being punished. I put them in a
   sack, and on a pitch black night I took them out under an arch. First I
   would cough and then whale the daylights out of the cats. They whined
   and shrieked like an infernal pipe organ. I would pause for awhile and
   repeat the operation—first a cough, and then a thrashing. I finally
   noticed that even without beating them, the beasts moaned and yelped
   like the very devil whenever I coughed. I then let them loose.
   Thereafter, whenever I had to eat off the floor, I would cast a look
   around. If an animal approached my food, all I had to do was to cough,
   and how that cat did scat!
          --Lope de Vega’s four-century-old play El Capellon de la Vergen
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Basic Processes in Classical
Conditioning

 Acquisition-- initial stage in learning, depends on
 Stimulus contiguity--occurring together in time and
  space
 Not all pairs of stimuli result in classical conditioning;
  greater chance w/ novel, unusual or intense stimuli
 Timing also important:
    – Simultaneous conditioning: CS and UCS begin and end
      together
    – Short-delayed conditioning: CS begins just before the
      UCS, end together (most effective)
    – Trace conditioning: CS begins and ends before UCS is
      presented
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Processes in Classical Conditioning
   Conditioned responses do not necessarily last indefinitely;
    Extinction—gradual weakening and disappearance of a
    conditioned response tendency; results from consistent
    presentation of conditioned stimulus w/o unconditioned stimulus
    (i.e. dentist drill)
   Spontaneous Recovery—reappearance of an extinguished
    response after a period of nonexposure to conditioned stimulus
     – Renewal effect– if response is extinguished in a different
       environment than it was acquired, returning to the original
       environment results in reappearance of response
     – Suggests that extinction suppresses conditioned responses rather
       than erasing learned associations




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Processes in Classical
Conditioning
   Stimulus Generalization—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 (i.e. Little Albert);
    greater the similarity the greater the generalization
   Stimulus Discrimination—when an organism that has learned
    a response to a specific stimulus does not respond in the same
    way to a new stimuli that are similar to the original (ex: dog,
    sound of car); less similar the new stimuli, the greater likelihood
    of discrimination
   Higher-order conditioning—a conditioned stimulus functions
    as if it were an unconditioned stimulus; new conditioned
    responses are built on foundation of already established
    conditioned responses (ex: Pavlov, red light)

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Brian Wilson
    --Barenaked Ladies
   Drove downtown in the rain                                  And if you want to find me
    Nine-thirty on a tuesday night,                              I'll be out in the sandbox,
    Just to check out the late-night                             Wondering where the hell all the
    Record shop.                                                 Love has gone,
    Call it impulsive                                            Playing my guitar and
    Call it compulsive,                                          Building castles in the sun and
    Call it insane;                                              Singing "Fun, Fun, Fun"
    But when I'm surrounded
    I just can't                                                 Chorus
    Stop.
                                                                 I had a dream
    It's a matter of instinct                                    That I was three hundred pounds
    It's a matter of conditioning                                And though I was very heavy
    It's a matter of fact.                                       I floated 'til I couldn't see the ground
                                                                 I floated 'til I couldn't see the ground
    Tou can call me Pavlov's                                     Somebody help me,
    Dog,                                                         I couldn't see the ground
    Ring a bell and I'll salivate -                              Somebody help me because I'm
    How'd you like that?
    Dr. Landy tell me                                            Chorus
    You're not just a pedagogue
                                                                 Drove downtown in the rain
    'cause right now I'm                                         Nine-thirty on a tuesday night,
                                                                 Just to check out the late-night
    Chorus:                                                      Record shop.
    Lying in bed                                                 Call it impulsive
    Just like Brian Wilson did                                   You can call it compulsive,
    Well I am                                                    You can call it insane;
    Lying in bed                                                 But when I'm surrounded
    Just like Brian Wilson did.                                  I just can't
                                                                 Stop.
    So I'm lying here
    Just staring at the ceiling tiles,
    And I'm thinking about
    Oh what to think about.
    Just listening and relistening
    To Smiley Smile,
    And wondering if this is some kind of creative drought
    Because I'm
    Chorus

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Operant Conditioning




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Operant Conditioning or Instrumental
Learning

   Classical conditioning best explains reflexive
    responding that is largely controlled by stimuli that
    precede the response
   What about responses that are influenced by
    stimulus events that follow the response—better
    described as “consequences”
    – learning is called operant conditioning (B.F. Skinner)—
      responses come to be controlled by their consequences
   Classical conditioning mostly reflexive; operant
    conditioning mostly voluntary—however some
    crossover

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Thorndike’s Law of Effect

   Operant conditioning also called instrumental
    learning (Edward L. Thorndike)
   Thorndike stressed that this kind of responding is
    often instrumental in obtaining some desired outcome
   Work provided foundation for Skinner’s work
   Attributed learning to the law of effect—if a response
    in the presence of a stimulus leads to satisfying
    effects, the association between the stimulus and the
    response is strengthened


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Skinner’s Demonstration: It’s All
a Matter of Consequences
 B.F. Skinner also demonstrated that organisms tend to repeat those
  responses that are followed by favorable consequences
 Reinforcement—occurs when an event following a response increases
  an organism’s tendency to make that response; leads to rewarding
  consequences
 Terminology:
    – Operant chamber (or Skinner box)– a small enclosure in which an animal
      can make a specific response that is recorded while the consequences of
      the response are systematically controlled
    – Since operant responses tend to be voluntary, they are said to be
      emitted—sent forth
    – Reinforcement contingencies—the circumstances or rules that determine
      whether responses lead to the presentation of reinforcers
    – Cumulative recorder—creates a graphic record of responding and
      reinforcement in a Skinner box as a function of time
        • Horizontal axis = passage of time; vertical axis = accumulation of responses
        • Rapid response rate produces steep slope; slow response rate produces shallow
          slope



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Basic Processes in Operant
Conditioning
   Acquisition—initial stage of learning some new pattern of
    responding, usually established through gradual process called
   Shaping– consists of the reinforcement of closer and closer
    approximation of a desired response; necessary when an
    organism doesn’t emit the desired response on its own; key
    process in animal training
   Extinction– gradual weakening and disappearance of a
    response tendency because response is no longer followed by a
    reinforcer; can begin w/brief surge in response when
    reinforcement ceases
    – Resistance to extinction—when an organism continues to make a
      response after delivery of the reinforcer for it has been terminated;
      depends on variety of factors, especially the schedule of
      reinforcement


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Basic Processes in Operant
Conditioning

   Discriminative stimuli—cues that influence operant
    behavior by indicating the probable consequences
    (reinforcement or nonreinforcement) of a response;
    reactions to discriminative stimuli governed by:
    – Generalization—responding to new stimuli as if it were the
      original
    – Discrimination—ability to discriminate between similar
      stimuli




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Reinforcement: Consequences that
Strengthen Responses

   Central process in reinforcement is the strengthening of a
    response tendency; can be effective at one time and not
    another; can be different among different people
   Delayed reinforcement—the longer the delay between
    designated response and delivery of reinforcer, the more slowly
    conditioning proceeds
   Primary Reinforcers—events that are inherently reinforcing
    because they satisfy biological needs (i.e. food, water, sex, etc.)
   Secondary Reinforcers—also called conditioned reinforcers–
    events that acquire reinforcing qualities by being associated with
    primary reinforcers (i.e. money, good grades, attention, etc.)


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Intermittent Reinforcement:
Effects of Basic Schedules
   In real life, most responses are reinforced only some of the time
   Schedule of reinforcement—determines which occurrences of
    a specific response result in the presentation of a reinforcer
     – Continuous reinforcement—simplest pattern; every instance of a
       designated response is reinforced
     – Intermittent (partial) reinforcement—designated response is
       reinforced only some of the time; more effective in yielding
       resistance to extinction
         • Fixed-ratio (FR) schedules—reinforcer is given after a fixed number
           of nonreinforced responses
         • Variable-ratio (VR) schedules– reinforcer is given after a variable
           number of nonreinforced responses
         • Fixed-interval (FI) schedules—reinforcer is given for the first
           response that occurs after a fixed time interval has elapsed
         • Variable-interval (VI) schedules– reinforcer is given for the first
           response after a variable time interval has elapsed


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Concurrent Schedules of
Reinforcement and the Study of
Choice
   Humans and other organisms constantly have to make choices
    between two ore more responses that are governed by
    independent schedules of reinforcement
   Concurrent schedules of reinforcement– two or more
    reinforcement schedules that operate simultaneously and
    independently, each for a different response
   Matching law—states that under concurrent schedules of
    reinforcement, organisms’ relative rate of responding to each
    alternative tends to match each alternative’s relative rate of
    reinforcement
   Optimal foraging theory—claims the food-seeking behaviors
    of many animals maximize the nutrition gained in relation to the
    energy expended to locate, secure, and consume various foods

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Positive Reinforcement Versus
Negative Reinforcement
   Increasing a response:
    – Positive reinforcement– response is strengthened because
      it is followed by a rewarding stimulus (i.e. good grades,
      promotions)
    – Negative reinforcement-- response is strengthened
      because it is followed by the removal of an aversive
      (unpleasant) stimulus (i.e. pain medicine, cleaning house)
       • Escape learning—an organism acquires a response that
         decreases or ends some aversive stimulation
       • Avoidance learning—an organism acquires a response that
         prevents some aversive stimulation from occurring; long-
         lasting, but why?
           – Two-Process Theory of Avoidance—the avoidance response
             removes an internal aversive stimulus (i.e. conditioned fear),
             rather than an external aversive stimulus (i.e. shock)
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Punishment: Consequences that
Weaken Responses
   Decreasing a response:
    – Punishment– occurs when an event following a response weakens
      the tendency to make that response
        • Can involve presentation of aversive stimulus (i.e. spanking) or removal
          of a rewarding stimulus (i.e. taking away cell phone)
    – Problems with punishment
        • Even when effective in weakening a response, can have unintended
          side effects, such as general suppression of behavioral activity (i.e.
          freezing up, becoming withdrawn) and/or triggering of strong emotional
          responses (i.e. fear, anxiety, resentment)
        • Studies show that physical punishment often leads to increase in
          aggressive behavior
    – Studies show that disciplinary goals can often be accomplished
      more effectively by reinforcing desirable behavior than by punishing
      undesirable behavior

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Changing Directions in the Study of
Conditioning
   Recognizing biological constraints on conditioning
     – Instinctive drift—occurs when an animal’s innate response tendencies
       interfere w/conditioning responses (i.e. raccoons)
     – Conditioned Taste Aversion – Garcia & Koelling (1966) – Figure 6.24
     – Preparedness—involves a species-specific predisposition to be
       conditioned in certain ways and not others; evolutionary basis; explains
       instinctive drift and conditioned taste aversion; some debate
     – Phobias—may be influenced by preparedness; certain phobias much more
       common (snakes, spiders, heights); most were genuine threats to our
       ancestors
   Recognizing cognitive influences on conditioning
     – Signal relations– assertion that some stimuli serve as signals and that
       some stimuli are better, or more dependable, signals than others; good
       signals allow for accurate prediction of the UCS
     – Response-outcome relations—when a response is followed by a
       desirable outcome, the response is more likely to be strengthened if the
       person thinks that the response caused the outcome

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Observational Learning

   Can classical and operant conditioning account for all
    learning?
    – No (i.e. learning to drive a car)
   Observational learning– occurs when an
    organism’s responding is influenced by the
    observation of others, who are called models
    – Albert Bandura claims that observational learning greatly
      extends the reach of classical and operant conditioning
        • Vicarious conditioning—responses conditioned indirectly by
          observing another’s conditioning


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Basic Processes of Observational
Learning

   4 key processes (Bandura)
    – Attention—to learn through observation, you must pay
      attention to another person’s behavior and its consequences
    – Retention– you must store a mental representation of what
      you have witnessed in your memory
    – Reproduction—enacting a modeled response depends on
      your ability to reproduce the response by converting your
      stored mental images into overt behavior
    – Motivation—you are unlikely to reproduce an observed
      response unless motivated to do so; depends on whether
      you encounter a situation in which you believe that the
      response is likely to pay off for you
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Acquisition Versus Performance

   According to Bandura, reinforcement affects which
    responses are actually performed more than which
    responses are acquired
   Differs from Skinner in that reinforcement is
    determinant in performance, not learning




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Bandura, Ross, & Ross (1963)
featured study - p. 245 – 246 –
Figure 6.26




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                              p. 245
Modify your own behavior?




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           Figures 6.28 and 6.29

								
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