Chapter 7 Learning

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Chapter 7Learning
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Habituation and sensitization

• Orienting Response A novel or surprising
  stimulus causes us to shift attention.
• Habituation You are exposed to a stimulus so
  often that your tendency to respond to it
  declines.
• Sensitization An intense stimulus makes
  responding to it more likely with repeated
  exposure.

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Definition of Learning

• Learning-a relatively durable change in behavior
  or knowledge that is due to experience
• Ivan Pavlov (1903 Pavlovian Conditioning)
• Classical Conditioning A type of learning in
  which a stimulus acquires the capacity to evoke a
  response that was originally evoked by another
  stimulus.

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Ivan Pavlov
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Figure 6.1Classical conditioning apparatus. An
experimental arrangement similar to the one
depicted here (taken from Yerkes Morgulis,
1909) has typically been used in demonstrations
of classical conditioning, although Pavlovs
original setup (see inset) was quite a bit
simpler. The dog is restrained in a harness. A
tone is used as the conditioned stimulus (CS),
and the presentation of meat powder is used as
the unconditioned stimulus (UCS). The tube
inserted into the dogs salivary gland allows
precise measurement of its salivation response.
The pen and rotating drum of paper on the left
are used to maintain a continuous record of
salivary flow. The inset shows the less elaborate
setup that Pavlov originally used to collect
saliva on each trial (Goodwin, 1991).
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Terminology

• Unconditioned Stimulus (UCS)-a stimulus that
  evokes an unconditioned response without previous
  conditioning
• Conditioned Stimulus (CS)-a previously neutral
  stimulus that has, through conditioning, acquired
  the capacity to evoke a conditioned response
• Unconditioned Response (UCR)-an unlearned
  reaction to an unconditioned stimulus that occurs
  without previous conditioning
• Conditioned Response (CR)-a learned reaction to a
  conditioned stimulus that occurs because of
  previous conditioning
• Trial-any presentation of a stimulus or pair of
  stimuli

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Figure 6.2 The sequence of events in classical
conditioning. As we encounter examples of
classical conditioning throughout the book, we
will see many diagrams like the one in the fourth
panel, which summarizes the process.
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Classical Conditioning in Everyday Life

• Phobias/Fear
• Ex a small child gets attacked by a dog, as an
  adult they shake and sweat every time they see a
  dog
• Pleasant Memories
• Ex Your first love wore Musk cologne. Now when
  you smell musk cologne you can only think of that
  person
• Conditioned immunosuppression
• Ex A decrease in the number of antibodies
  produced in the immune system in response to a
  taste like sugar water after it was paired with
  an immunosuppressive drug

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Basic Processes in Classical Conditioning

• Acquisition-formation of a new conditioned
  response tendency
• Extinction-the gradual weakening and
  disappearance of a conditioned response tendency
• Spontaneous Recovery-a reappearance of an
  extinguished response after a period of
  nonexposure to the conditioned stimulus
• 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 stimulus

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Basic Processes in Classical Conditioning

• Classic Study Little Albert John B. Watson
• 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
• Higher-order conditioning-a form of classical
  conditioning in which a conditioned stimulus
  functions as if it were an unconditioned stimulus

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Operant Conditioning

• A form of learning in which voluntary responses
  come to be controlled by their consequences
• Allows for Reinforcement contingencies-circumstanc
  es or rules that determine whether responses lead
  to the presentation of reinforcers
• Reinforcement occurs when an event following a
  response increases an organisms tendency to make
  that response

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Figure 6.11 Skinner box and cumulative recorder.
(a) This diagram highlights some of the key
features of a Skinner box. In this apparatus
designed for rats, the response under study is
lever pressing. Food pellets, which may serve as
reinforcers, are delivered into the food cup on
the right. The speaker and light permit
manipulations of visual and auditory stimuli, and
the electric grid gives the experimenter control
over aversive consequences (shock) in the box.
(b) A cumulative recorder connected to the box
keeps a continuous record of responses and
reinforcements. Each lever press moves the pen up
a step, and each reinforcement is marked with a
slash. (c) This photo shows the real thinga rat
being conditioned in a Skinner box. Note the food
dispenser on the left, which was omitted from the
top diagram.
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Processes in Operant Conditioning

• Shaping-reinforcement of closer and closer
  approximations of a desired response
• Acquisition-refers to the initial stage of
  learning some new pattern of responding
• Extinction-the gradual weakening and
  disappearance of a response tendency because the
  response is no longer followed by a reinforcer
• Resistance to extinction-occurs when an organism
  continues to make a response after delivery of
  the reinforcer for it has been terminated
• Generalization-when responding increases in the
  presence of new stimuli that resembles the
  original discriminative stimulus
• Discrimination-when responding does not increase
  in the presence of a new stimulus that resembles
  the original discriminative stimulus

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Figure 6.13 Extinction in operant conditioning.
Extinction begins when a response is no longer
followed by a reinforcer. Responding persists for
a time, but extinction eventually produces a
gradual decline in response rate, as can be seen
in both graphs of extinction shown here.
Responses that are more resistant to extinction
taper off more slowly (top graph) than responses
that are less resistant to extinction (bottom
graph).
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Reinforcement Consequences That Strengthen
Responses

• Delayed Reinforcement-the longer the delay
  between the designated response and the delivery
  of the reinforcer, the more slowly conditioning
  proceeds
• Primary Reinforcers-events that are inherently
  reinforcing because they satisfy biological needs
• Secondary Reinforcers-events that acquire
  reinforcing qualities by being associated with
  primary reinforcers

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Schedules of Reinforcement

• Continuous vs Intermittent Reinforcement
• Variable Ratio-the reinforcer is given after a
  variable number of nonreinforced responses
• Variable Interval-the reinforcer is given for the
  first response after a variable time interval has
  elapsed
• Fixed Ratio-the reinforcer is given after a fixed
  number of nonreinforced responses
• Fixed Interval-the reinforcer is given for the
  first response that occurs after a fixed time
  interval has elapsed

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Positive Reinforcement Versus Negative
Reinforcement Versus Punishment

• Positive Reinforcement-occurs when a response is
  strengthened because it is followed by the
  presentation of a rewarding stimulus
• Negative Reinforcement-occurs when a response is
  strengthened because it is followed by the
  removal of an aversive stimulus
• Punishment-occurs when an event following a
  response decreases the tendency to make that
  response

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Figure 6.18 Comparison of negative reinforcement
and punishment. Although punishment can occur
when a response leads to the removal of a
rewarding stimulus, it more typically involves
the presentation of an aversive stimulus.
Students often confuse punishment with negative
reinforcement because they associate both with
aversive stimuli. However, as this diagram shows,
punishment and negative reinforcement represent
opposite consequences that have opposite effects
on behavior.
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Applications of Operant Conditioning

• Day to Day Life Examples
• Escape/Avoidance Learning
• Payroll
• Gambling

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Observational Learning
Defined-occurs when an organisms responding is
influenced by the observation of others

• Four Processes (Bandura)
• Attention-You must pay attention to another
  persons behavior and its consequences
• Retention-You must store a mental representation
  of what you have witnessed in your memory
• Reproduction-Your ability to reproduce the
  response by converting your stored mental images
  into overt behavior
• Motivation-Your motivation 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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Putting It In Perspective

• Nature and nurture interactively govern behavior
• There are dense interconnections between
  psychology and events in the world at large

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Application

• Achieving Self-Control Through Behavior
  Modification