Operant Reinforcement

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Operant Reinforcement
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Definition of Operant Reinforcement

• Operant Reinforcement is said to have occurred
  when a behavior is followed immediately by the
  presentation of some stimulus and, as a result,
  occurs more often in the future.
• Operant reinforcement strengthens a response
  class of behaviors, not just a single behavior.
• A response class is a set of behaviors related by
  their functional similarity.

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Definition of Operant Reinforcement

• To illustrate the concept of a response class, we
  might consider the typing behavior of a high
  school business education student.
• The downward movement of the keys produces
  changes in the environment in the form of letters
  on paper.
• A single key stroke is part of a response class
  of key stroking behaviors.
• The student could hit the key slightly off
  center, with varying degrees of pressure, or with
  one finger in a hunt-and-peck method.
• Even though these behaviors have different
  topographies, they belong to the same response
  class because they are functionally equivalent
  (i.e., they each produce the same effect on the
  environment.

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Positive Reinforcement

• Positive Reinforcement is the most widely applied
  principle of behavior.
• Three conditions are necessary for reinforcement
• First, a response must have some consequence.
• Second, the response must increase in probability
  (i.e., the response must be more probable than
  when it does not have this consequence).
• Third, the increase in probability must occur
  because the response has this consequence, and
  not for some other reason.
• The stimulus, or event, that follows the behavior
  and is administered contingently is termed the
  positive reinforcer.

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Advantages of Positive Reinforcement

• The obvious advantage of positive reinforcement
  is that it can be used to increase the future
  probability of a wide range of behaviors.
• It can be used to produce new behaviors, or it
  can be used to refine the topography, frequency,
  or duration of existing behaviors.
• The latter procedure is termed differential
  reinforcement because the reinforcer is applied
  to one member of a response class of behavior and
  not to other members.
• The member of the class of behavior to which the
  reinforcer is applied increases, whereas members
  not reinforced decrease in probability.

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Negative Reinforcement

• Negative reinforcement has erroneously been
  thought of as a punishment procedure or a highly
  aversive reductive procedure when, in fact, it is
  a procedure for increasing operant behavior.
• Negative reinforcement is a reduction or
  termination of an ongoing stimulus, contingent
  upon a response that results in the increased
  likelihood of the behavior occurring again under
  similar stimulus conditions.
• The stimulus that is removed is termed the
  negative reinforcer.

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Contingencies Related to Negative Reinforcement

• Escape
• Escape terminates an existing stimulus. A
  frequent episode in classrooms shows how escape
  operates.
• A teacher might be faced with a situation in
  which two students are name calling loudly in
  class, and the name calling persists for several
  minutes. The teacher might tell the students to
  stop bickering, and they might do so momentarily.
  At this point the teacher has been negatively
  reinforced because his response (telling the
  students to stop bickering) terminated the
  stimulus (the bickering). He escaped the
  stimulus, making it more likely that he will
  verbally reprimand the students again the next
  time they bicker.

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Contingencies Related to Negative Reinforcement

• Avoidance
• Avoidance occurs when a response avoids, rather
  than terminates, a stimulus.
• A student might follow a teachers verbal
  directions to avoid having to go to the
  principles office. Another student might sit in
  the back of the bus to avoid being teased by his
  classmates. A child might walk through a novelty
  shop with her hands in her pockets to avoid
  having her mother tell her not to touch things on
  the shelves. In each case the individuals
  response avoided the experience of the stimulus.

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Disadvantages of Negative Reinforcement

• Negative reinforcement has two disadvantages.
• First, it is possible that if negative
  reinforcement is used too often, individuals will
  simply avoid situations or settings in which
  aversive stimuli are present.
• Second, aggressive or emotional operants might be
  directed at the source of the aversive stimulus
  (e.g., teachers or parents).

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Types of Potential ReinforcersPrimary Reinforcers

• Primary or unconditioned reinforcers are stimuli
  or events that, by virtue of their biological
  importance, serve as consequences to increase the
  probability of behaviors immediately preceding
  them.
• Food, water, oxygen, warmth, and sexual
  stimulation are examples of stimuli that do not
  have to undergo a conditioning process to serve
  as positive reinforcers.
• In a state of deprivation, they reinforce
  behavior automatically.
• They are also automatic in the sense that the
  individual does not have to be aware that the
  stimulus is a reinforcer.

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Types of Potential ReinforcersSecondary
Reinforcers

• Secondary or conditioned reinforcers can be
  defined as those initially neutral stimuli that
  have acquired reinforcing capability because of
  being paired with primary reinforcers or
  established reinforcers.
• A sound, a color, an odor any stimulus can be
  become a conditioned reinforcer by being paired
  with primary or established reinforcers.

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Secondary ReinforcersFour Subcategories

• Tangible Reinforcers
• A tangible reinforcer is an object or activity
  that increases the future probability of a
  behavior when the reinforcer is presented
  subsequent to the emission of that behavior.
• Trinkets, pins, emblems, marbles, and toys serve
  as examples, or potential tangible reinforcers.

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Secondary ReinforcersActivity-Oriented
Reinforcers

• An activity-oriented reinforcer is an event or
  privilege such as helping the teacher, playing a
  game, going to the movies, or having lunch with
  parents.

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Secondary ReinforcersSocial Reinforcers

• Social reinforcers can be three varieties.
• They can be physical contacts (e.g., hugs,
  kisses), proximity (i.e., standing or sitting
  near an individual), or verbal statements (e.g.,
  Very Good).
• Verbal statements can be further subdivided into
  statements of affirmation or information.
• An example of an affirmative praise statement is
  Sue, that is the correct answer.
• An informational praise statement describes the
  specific behavior that prompted the praise
  Rich, your lower case letters touched the line
  as they should.

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• A Generalized reinforcers is a type of
  conditioned reinforcer the effectiveness of which
  does not depend upon a single kind of
  deprivation.
• Tokens and money serve as generalized reinforcers
  because they provide the individual with access
  to a wide range of other primary or secondary
  reinforcers.
• When tokens symbols or objects are delivered
  subsequent to a behavior, they serve as an
  interim reinforcer.
• The token is exchanged for a back-up reinforcer
  at a later time.
• A generalized reinforcer can maintain behavior
  over extended time periods and is less likely to
  lead to satiation.
• Satiation is the condition that exists when an
  overabundance of a reinforcer has been provided
  with a corresponding decrease in the future
  occurrence of the behavior.
• In short, the reinforcer has lost its reinforcing
  properties.

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Selecting Potential Reinforcers

• Asking
• The most basic method for determining a potential
  reinforcer is to ask what the individual prefers.
• Observing
• Watching what an individual does on a regular
  basis can provide a valuable source of
  information on what activities or events can be
  used as potential reinforcers.
• Reinforcer Sampling
• In reinforcer sampling the individual is
  presented with a sample of the potential
  reinforcer in order to gain experience with it.
  The potential reinforcer is not presented
  contingently the individual merely experiences
  it.
• Trying and Seeing
• The only way to determine whether any potential
  reinforcer will actually serve as a reinforcer is
  to try it and see.

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The Premack Principle

• The Premack Principle, sometimes called
  Grandmas Law, states that access to high
  frequency behavior is contingent upon the
  occurrence of low frequency behavior You can
  eat your ice cream (high frequency behavior)
  when you have finished your vegetables (low
  frequency behavior).
• The rational for the Premack Principle is that a
  high frequency behavior can serve as a reinforcer
  for a low frequency behavior.

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Factors Influencing The Effectiveness of
Reinforcement

• There are at least four sets of variables that
  affect reinforcement genetic factors, an
  individual history of reinforcement, the current
  environment, and the deprivation state of the
  individual.
• To date, it has not been possible to alter the
  genetic endowment of individuals.

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History of Reinforcement

• A persons history of reinforcement refers to the
  frequency, intensity, and/or duration with which
  particular responses have been reinforced in the
  presence of particular stimulus conditions.
• Each persons history of reinforcement is a
  cumulative set of experiences and is unique to
  that person.

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Current Environment

• At least six factors in the current environment
  influence the effectiveness of reinforcement
  timing, consistency, amount, quality, schedule,
  and novelty.
• Timing. The timing of reinforcement exists on a
  continuum from immediate to delayed. As a
  general rule, immediate reinforcement is
  necessary if a behavior is to be increased or
  maintained.
• Consistency. To reinforce a behavior with
  consistency means that the behavior is reinforced
  according to the requirements of an established
  schedule of reinforcement. Regardless of whether
  the schedule is continuous or intermittent,
  consistency in delivery of the reinforcer is
  necessary.

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Current Environment

• Amount of Reinforcement. The amount of a
  reinforcer that an individual receives also
  affects the reinforcement program. Consideration
  of how much reinforcement to use should follow
  the maxim Reinforce abundantly, but dont give
  away the store. The consensus is that the amount
  of reinforcement should be proportional to the
  effect involved in making the response. However,
  when initiating a behavior change program,
  additional reinforcement must be used in order to
  establish the behavior.

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Quality. The quality of a reinforcer is important
to consider in behavior change programs. A toy
with lights, changeable components, and movement
functions is probably a more powerful reinforcer
than a red wagon for most children. The quality
of the reinforcer is relative to other
reinforcers in the environment and can be used
contingently to improve behavior. Novelty. The
more varied and different reinforcers are from
one another, the more likely it is that they can
be used to increase behavior. From a behavioral
perspective the usefulness of novel reinforcers
might be explained in two ways. First, the more
novel the reinforcer, the more likely that the
person is deprived of the reinforcer. The more
deprived the person, the more likely that the
stimulus will have a reinforcing effect. Second,
the more novel the reinforcer, the less likely
that the person will experience satiation.
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Deprivation State

• For reinforcement to be effective, the subject
  must experience some level of deprivation prior
  to delivery of the reinforcer. Food is not as
  reinforcing to a person who has just had a full
  meal as it is to an individual who has not eaten
  in several days.
• The rule to follow is that if a reinforcer is
  going to be used, the subject should be deprived
  of it prior to its presentation and should not
  have access to it in other environments or under
  other conditions.

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Establish an Appropriate Criterion for
Reinforcement

• The first step in establishing a reinforcement
  schedule is to set the initial criterion.
• Heward (1980) devised a formula that uses
  baseline data to determine the level for
  reinforcement in an instructional setting.
• For a behavior you wish to increase, set the
  initial criterion higher than the childs average
  baseline performance and less than or equal to
  his best performance during baseline. For a
  behavior you want to decrease in frequency, the
  initial criterion for reinforcement should be set
  at less than the childs average performance
  during baseline and greater or equal to his
  lowest (or best) baseline performance.

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Choose the Appropriate Reinforcer

• Age appropriate, novel, and natural reinforcers
  be used whenever possible.
• No reinforcement approach is likely to be
  successful if an inappropriate, nonfunctional
  reinforcer is used.

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Use Generalized Conditioned Reinforcers

• As stated previously, tokens, points, and money
  make effective reinforcers because the individual
  can exchange these interim reinforcers for other
  back-up primary or secondary reinforcers that are
  scheduled to be delivered at a later time.

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Reinforce Appropriate Behavior Immediately and
Often

• Probably the single most important action of a
  practitioner attempting to develop new responses
  is to reinforce the occurrence of the desired
  behavior immediately after it is emitted.
• Catch em being good

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Use Reinforcement Across Settings, Behaviors, and
Time

• Operationally, practitioners reinforcing
  appropriate behavior in one setting or time
  should see to it that the occurrences of that
  behavior are reinforced in other settings or at
  other times.

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Use Cues to Prompt Behavior

• Practitioners should not hesitate to use
  supplemental cues to prompt behavior. Visual,
  verbal, or physical prompts can set the occasion
  for a behavior to occur and be reinforced.