Ps635 Concept Formation Caldwell College Master of Arts in Applied Behavior Analysis Dr' Ken Reeve

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Ps635 Concept FormationCaldwell CollegeMaster
of Artsin Applied Behavior AnalysisDr. Ken
Reeve
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In the beginning

• A person learned a skill (or response or
  behavior)
• And it was good
• And the almighty behavior analyst said

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Let there be different contexts

• in which the behavior should and should not
  occur
• And the behavior analyst said, let us now study
  stimulus control!
• And this begat the notions of
• Generalization
• Discrimination
• Discriminative stimuli
• Prompts of all manner and kinds
• Simple and complex antecedent stimuli
• Prompt Stimulus Fading
• Errorless learning MOREgtgt

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• Relevant and irrelevant stimulus characteristics
• Stimulus features
• Stimulus dimensions
• Intra-, Inter-, and Extra-dimensional
  generalization and discrimination
• Simple and conditional discriminations
• Delayed match-to-sample
• Object labeling
• Multiple exemplar training
• Over-selectivity problems
• Programming for generalization MOREgtgtgt

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• Concept formation
• Natural categories
• Fuzzy categories
• Relational classes
• Equivalence classes
• Relational Frame theory
• Etc.
• And the behavior analyst said, We have a lot to
  study, folks!

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Stimulus Control

• controlling stimuli antecedent events that
  precede operant (or respondent) behavior that
  affect likelihood of occurrence (we will mostly
  focus on operant behavior)
• A controlling stimulus (S) is said to alter the
  probability of an operant, in the sense that the
  response is more (or less) likely to occur when
  the stimulus is present.
• Discriminative stimulus (SD) or (S) - a
  controlling stimulus that sets the occasion for
  reinforcement of an operant.
• S-delta (S?) or (S-) or extinction stimulus - a
  stimulus that sets the occasion for extinction of
  an operant.

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Emitted versus evoked

• Operants can and do occur in the absence of any
  eliciting stimulus (they are said to be freely
  emitted).
• However, when an SD comes to control occurrences
  of an operant (to alter its probability of
  occurring), then we say that the SD evokes the
  operant.
• The term evoke dictates that the operant is under
  the stimulus control of an antecedent stimulus.

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Differential Reinforcementfor SD or S?

• When a person responds in one situation but not
  in another, we say that the person shows a
  discrimination between the situations.
• simplest way to teach differential responding
  (a/k/a discrimination) is to reinforce an operant
  in one situation and withhold reinforcement in
  the other
• Stimulus control refers to a change in behavior
  that occurs when either an SD or S? is presented.
  
• When SD presented, probability of response
  increases when S? is presented, probability of
  response decreases.

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Generalization vs. Discrimination

• DISCRIMINATION target behavior occurs in one
  situation but not in another
• We discriminate among settings, people, stimuli
• GENERALIZATION respond similarly in different
  situations
• We generalize across settings, people, stimuli

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Stimulus Generalization

• operant is emitted in presence of new stimuli
  (called transfer of control)
• new stimuli presumably share common properties
  with the original discriminative stimulus
• Generalization and discrimination refer to
  differences in the precision of stimulus control.
• Discrimination and generalization are inversely
  related (as one goes up the other goes down)

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Generalization Gradient

• A generalization gradient shows the relationship
  between the probability of response and stimulus
  value.

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Studying Stimulus Control

• To study generalization gradients, the researcher
  may arranges the presentation of SD or S? so that
  one follows the other (called successive
  discrimination training).
• In alternative procedure, simultaneous
  discrimination, the SD and the S? are presented
  at the same time and the organism responds to one
  or the other.
• In conditional disctrimination, the presence of a
  sample stimulus dictates which of two or more
  compariosn stimuli organism should select.

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Errorless Discrimination and Fading

• When the SD and the S? are alternately presented
  as in successive discrimination, the organism
  initially makes many errors.
• That is, person continues to respond in the
  presence of the S? because generalization often
  occurs unless you teach otherwise.
• As discrimination training progresses, a
  differential response occurs to the SD and S?.

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Problems with Regular DiscriminationTraining
Procedures

• BASIC RESEARCH IN REGULAR DISCRIMINATION
  TRAINING pigeon taught to peck (R) a green key
  (SD) for food (Sr).
• Once behavior is well established, color on key
  is changed to blue (S?) and pecking not
  reinforced
• blue and green colors are alternately presented
• During early training sessions, onset of
  extinction will generate emotional behavior that
  interferes with ongoing operant behavior. (Bird
  is Mad!)

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Problems with Regular DiscriminationTraining
Procedures

• Extinction is an aversive procedure!
• Pigeons flap their wings aggressively and will
  work for an opportunity to attack another bird
  during the presentation of S? !
• Birds will even peck a different key if pecking
  turns off the extinction stimulus (S?), implying
  that the stimulus is aversive. (this is an
  avoidance behavior!)

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Problems with Regular DiscriminationTraining
Procedures

• Because emotional behavior is elicited by the
  frustrating trial and error, discriminative
  responding takes a long time to develop!
• Sois there a better option?

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Yes Errorless Discrimination

• Here, the teacher does not allow the organism to
  make mistakes by responding to the extinction
  stimulus S?.
• Errorless discrimination involves gradually
  introducing the S? initially at a very weak
  intensity so that responding to it is very low
  in probability. Thus, person is actually
  practicing NOT responding to it.
• Over repeated trials, intensity of the S?
  gradually increased.
• Eventually S? is presented in full intensity and
  the person will not respond to it.
• So, a discrimination between the (SD) and the S?
  was acquired without the errors of responding to
  the S?.

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FADING

• When some stimulus ALREADY occasions a response,
  but we want to have a DIFFERENT stimulus occasion
  the response, then we might use a FADING
  PROCEDURE
• PROMPT an artificial SD that we use to make a
  behavior likely to occur when the natural SD is
  ineffective
• We then gradually reduce (FADE OUT) the prompt so
  that the control of the behavior transfers to the
  natural SD
• Sometimes we FADE IN the natural SD

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More on FADING

• Sometimes we can morph an artificial SD into
  the natural SD
• This can be done with morphing software.
• Often done where a picture is morphed into a word
  over successive trials so that the word will
  control a verbal label such as CAT.

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COMPLEX STIMULUS CONTROL

• Refers to situations in which the behavioral
  function of an antecedent stimulus changes
  depending on the presence of another stimulus.
• That is, in some situations, a stimulus might be
  an SD and in other situations the S?
• This is called CONDITIONAL DISCRIMINATION
  LEARNING because the correct response is
  conditional on (dependent on) another
  antecedent
• A CONDITIONAL DISCRIMINATION is an IF-THEN rule

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CONDITIONAL DISCRIMINATION MATCHING TO SAMPLE

• Because in conditional discrimination training,
  the conditional stimulus is referred to as a
  SAMPLE and the choices we respond to are called
  COMPARISON STIMULI, this is also called MATCHING
  TO SAMPLE (MTS) because you are trying to make
  the correct response in the presence of the
  sample
• Did you know? A multiple-choice exam question is
  a type of matching to sample or conditional
  discrimination trial!

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EXAMPLE OF CONDITIONAL DISCRIMINATION

• For a child, the stimulus of MOMMY being present
  is usually an SD for talking to her
• But WHAT IF mommy and the child are in church or
  temple?
• Note that the correct response to mommy (being
  quiet) is conditional on (dependent on) the
  setting in this case.
• What instructions would REVERSE the behavioral
  functions of the stimuli?

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Concept Formation

• Traditional cognitive psychology talks about the
  internal mental rules defining what things go
  together and why they assert that the mental
  rule controls behavior
• Behavior analysts refer to concepts as sets of
  stimuli that occasion a common response
• Those sets of stimuli can be incredibly complex
  such as exemplars of immoral conduct
• The common response can also be complex

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Concept stimulus class

• Behavior analysts identify the characteristics of
  the stimuli in the concept that controls the
  behavior
• They also examine how certain kinds of training
  (discrimination training, programming for
  generalization) affect the likelihood of stimulus
  classes (see work of Reeve, haha!)

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Stimulus Class Types

• PERCEPTUAL CLASS stimuli in the set share some
  physical characteristics
• RELATIONAL CLASS stimuli in the set share some
  abstract relationship, such as examples of
  bigger than.
• EQUIVALENCE CLASS stimuli do NOT share any
  physical characteristics. Stimuli belong together
  just because society says so.
• Example 1 one spoken word WUN

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Non-Human Studies on Natural Concept Formation

• Herrnstein - Pigeons
• Pigeons can learn to form concepts of a person as
  discriminated from non-persons, i.e., statues,
  mannequins, etc., a specific person from others,
  etc. The abstract stimulus class of person
  readily learned.
• Pigeons can learn to form natural concepts of
  persons, trees, fish, etc., with a high degree of
  accuracy. Artificial concepts such as buildings
  also learned.
• Pigeons appear to respond to two-dimensions
  objects (photographs) as representations of three
  dimensional objects

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Benefits of Conceptual Behavior

• Something for nothing
• New behavior occurs without training
• Reduced teaching load
• Less need to explicitly teach everything
• Economical
• See above
• Psychic power!
• can make predictions about something even if
  youve never encountered that specific something
  before)