Conditional Discriminations

Conditional Discrimination

Those for which the role of one stimulus depends on others that provide its context

Bias

a preference for one alternative over another, despite consequences programmed for selections.

Match to Sample

sample stimulus is presented

response initiates comparison stimuli

matching responses are reinforced

Oddity Matching

a conditional discrimination procedure in which one of three or more stimuli differ from the others in some property.

Big Bird from Seasame Street is an example

Arbitrary Matching

• Conditional discrimination procedure in which matches are based on arbitrary relations.

• there is no point-to-point correspondence for the sample and the correct stimulus

Stimulus Equivalence

• SR+ = Positive Reinforcement = Contingent

• presentation of a stimulus that results in an increase in the future probability of a behavior.

What is Symmetry and how is it established?

• refers to the reversibility of a relationship

  • if A= B, then B=A

• Established

  • The color blue is our “A“ class

  • The shape “triangle“ is our “B“ class.

  • We do this over and over, until we have taught “blue equals triangle

  • Ex: if the bird can reliably peck “triangle“ given a blue sample, then when given triangle as the sample, the bird should easily be able to peck “blue“ as the match.

Transitivity

• transfer of the relation to new combinations through shared membership

• with transitive relations that we seek to identify emergent relations

  • If A=B and B=C, then A=C

• Established

  • the shape “triangle“ is our “B” class, bowtie shape is C class

  • given triangle as the sample, the bird will learn to select the “bow tie“ shape.

  • the A-C and C-A relations were never taught, these new relations should emerge based on what is known.

Stimulus Equivalence refers to…

• reflexivity, symmetry and transitivity

• can only exist when all are present.

What are the procedures used to establish conditional discriminations?

• Match to Sample (identity matching)

• Oddity Matching

• Arbitrary Matching

Procedure and Example of Match to Sample

• sample stimulus is presented → response on the sample stimulus initiates comparison stimuli → matching responses are reinforced.

• Ex: discrete trial training, “"point to the duck” experiment.

• Ex 2: green as sample means select green as match.

Procedure and Example of Oddity Training

• a conditional discrimination procedure in which one of 3 or more stimuli differ from the others in some property.

• responses to the “odd“ one are reinforced.

• Ex: green as sample means select red as match.

Procedure and example of arbitrary matching

• conditional discrimination procedure in which matches are based on arbitrary relations

• there is no point to point correspondence for the sample and the correct stimulus.

• Ex: green as sample means select pizza to match

Examples of Bias?

• Handedness: inclined to make a selection that is “on the right“

• Effort: a bias might emerge because one option is more effortful (more difficult than another.)

• Color: a bias might emerge because of a color preference.

What is discrete trial training? and why is it important?

• used to establish a verbal repertoire for individuals with intellectual disabilities (like Autism)

• if a child exhibits a “side bias” (as in the duck example), we may conclude that the child has acquired particular skills, when in fact the child has not.

• Rather, the teacher’s behavior is the one that is changing (the teacher is learning, but the child is not).

• conservatively, this means we should truly use a random rotation when presenting stimuli in a discrete trial training format.

Examples of establishing stimulus equivalence

• definition: equivalence class is a stimulus class produced via matching to sample procedures, and includes emergent relations among its members

• Ex: SR+ = positive reinforcement = contingent

  • presentation of a stimulus that results in an increase in the future probability of behavior,

• Equivalence Class = reflexivity, symmetry and transitivity.

What are Emergent Relations?

• relations demonstrated without explicit instruction

• stimulus equivalence teaching paradigm is that you can get more learning, with less teaching

• aka teaching two skills can result in the emergence of four skills.

Reflexivity

• the matching of a sample to another of the same identity

• reflexivity = identity matching = match to sample.

  • A=A, or Green = Green

• Established

  • the color blue is our A class

  • we do this over and over, until we have taught “peck blue when you see a blue sample“