RBT Task List – Skill Acquisition (C-07)

Having covered the structured methods of Discrete-Trial Teaching (C-04), the client-led approach of Naturalistic Environment Teaching (C-05), and the process for teaching multi-step behaviors via task analyzed chaining procedures (C-06), we now arrive at a fundamental process that underlies much of what we call learning.

Let’s embark on a comprehensive exploration of:

C-07: Use Discrimination Training Procedures

Think about how we learn to stop at a red light but go on green, pick out our favorite brand of cereal from a crowded shelf, or respond correctly when asked for a “spoon” versus a “fork.” All of these involve discrimination.

Discrimination training is how individuals learn to “tell the difference” between various stimuli and respond appropriately in different situations.

It’s a foundational aspect of learning language, understanding social cues, mastering academic concepts, and so much more.

What is Discrimination Training?

Discrimination training is a fundamental behavioral procedure used to teach learners to respond differently to different stimuli.

Essentially, it’s teaching them to “discriminate” or “tell the difference” between situations, objects, instructions, or cues.

The goal is for them to make the correct response in the presence of one stimulus (or set of stimuli) and not in the presence of others.

This process results in stimulus control, where a specific behavior is more likely to occur in the presence of a particular stimulus (the Sᴰ Discriminative Stimulus) because that behavior has been reinforced in its presence.

Conversely, the behavior is less likely to occur in the presence of another stimulus (the Sᐞ – S-delta) because the behavior has not been reinforced (or has been extinguished or even punished) in its presence.

As an RBT, you’ll implement discrimination training procedures constantly. Examples include:

• Teaching a child to pick a red card (Sᴰ) and not a blue card (Sᐞ) when asked for “red.”
• Teaching a client to say “cat” when shown a picture of a cat (Sᴰ) and not when shown a dog (Sᐞ).
• Teaching a student to raise their hand in class when the teacher asks a question (Sᴰ) but not when another student is talking (Sᐞ).

The core goal of discrimination training is to bring a specific behavior under the control of appropriate antecedent stimuli, leading to the learner responding correctly and appropriately in various situations.

Key Concepts You Need to Know

• Discriminative Stimulus (Sᴰ):
  • Definition: An antecedent stimulus that signals the availability of reinforcement for a particular response. When the Sᴰ is present, a specific behavior is more likely to be reinforced.
  • Example: The written word “WALK” at a crosswalk is an Sᴰ for the behavior of walking across the street (as this behavior is safe/reinforced when “WALK” is present). A green traffic light is an Sᴰ for pressing the gas pedal.
• S-delta (Sᐞ):
  • Definition: An antecedent stimulus that signals that reinforcement is not available for a particular response, or that the response will undergo extinction or punishment if it occurs.
    When the Sᐞ is present, a specific behavior that is reinforced in the presence of the Sᴰ is not reinforced.
  • Example: The written words “DON’T WALK” (or a red hand symbol) at a crosswalk is an Sᐞ for the behavior of walking across the street (as walking is not safe/reinforced, and may be punished, when “DON’T WALK” is present).
    A red traffic light is an Sᐞ for pressing the gas pedal.
• Stimulus Control:
  • Definition: This occurs when the rate, latency, duration, or amplitude of a response is altered in the presence of an antecedent stimulus (the Sᴰ).
    The behavior occurs reliably in the presence of the Sᴰ and rarely or not at all in its absence or in the presence of the Sᐞ.
    Discrimination training is the process used to establish stimulus control.
• Differential Reinforcement (within Discrimination Training):
  • Definition: This is the core mechanism of discrimination training. It involves two key actions:
    • Reinforcing a specific response when it occurs in the presence of the Sᴰ.
    • Not reinforcing (i.e., putting on extinction) the same response when it occurs in the presence of the Sᐞ (or any other stimulus).
  • Process:
    • Response in presence of Sᴰ -> Reinforcement (SR+)
    • Response in presence of Sᐞ -> No Reinforcement (Extinction)
  • Over time, the learner “discriminates” that the response “pays off” only when the Sᴰ is present.

Common Discrimination Training Procedures You’ll Implement

RBTs use various formats for discrimination training, often within DTT or NET paradigms, as directed by the skill acquisition plan:

• Successive Discrimination Training:
  • How it works: Only one antecedent stimulus (either the Sᴰ or an Sᐞ) is presented at a time in a trial.
    The learner makes a response, and reinforcement is delivered if the Sᴰ was present and the correct response occurred.
    If an Sᐞ was present, the response is not reinforced. Stimuli are presented one after another across trials.
  • Example (Teaching “cat” vs. “dog” tacts):
    • Trial 1: RBT shows picture of a cat (Sᴰ for saying “cat”), asks “What is it?” -> Client says “Cat” -> Reinforcement.
    • Trial 2: RBT shows picture of a dog (Sᐞ for saying “cat” if that’s the error), asks “What is it?” -> Client says “Cat” -> No reinforcement (error correction might follow).
    • Trial 3: RBT shows picture of a dog (Sᴰ for saying “dog”), asks “What is it?” -> Client says “Dog” -> Reinforcement.
• Simultaneous Discrimination Training:
  • How it works: Both the Sᴰ and one or more Sᐞs are present at the same time during a trial.
    The learner must respond to the Sᴰ and not to the Sᐞ(s) to receive reinforcement. This is very common when teaching receptive identification (“point to,” “touch,” “give me”).
  • Example (Teaching receptive ID of “red” from an array of colors):
    • RBT presents a red card (Sᴰ) and a blue card (Sᐞ) simultaneously.
    • RBT gives the instruction (Sᴰ for the selection response): “Point to red.”
    • If client points to red card -> Reinforcement.
    • If client points to blue card -> No reinforcement (error correction).
  • Array Size: The number of Sᐞs present can be gradually increased as the learner becomes more proficient (e.g., starting with an array of 2, then 3, then 4 items).
• Matching-to-Sample (MTS):
  • What it is: A specific type of simultaneous discrimination training procedure used to teach conditional discriminations (i.e., “if-then” discriminations if this sample stimulus is present, then this comparison stimulus is the correct choice).
    The learner is presented with a sample stimulus and then must select the corresponding stimulus from an array of two or more comparison stimuli.
  • Types:
    • Identity Matching: Matching identical stimuli (e.g., picture of a cat to another picture of a cat; object to object).
    • Symbolic/Arbitrary Matching: Matching non-identical but related stimuli (e.g., picture of a cat to the written word “CAT”; a spoken word “car” to a picture of a car). This is foundational for reading and many academic skills.
  • Procedure:
    • Present the sample stimulus (e.g., RBT holds up a picture of a red circle – the sample).
    • Present an array of comparison stimuli (e.g., a red circle, a blue square, a yellow triangle – the comparisons).
    • Deliver the instruction (often implied by the presentation, or could be “Match” or “Find the same”).
    • Learner selects one comparison stimulus.
    • Reinforce selection of the correct comparison (the one that matches the sample).
  • RBT Role: Present sample and comparisons clearly, ensure client attends, reinforce correct matches, implement error correction for incorrect matches, and systematically introduce new matches as per the plan.

Key Steps for Effective Discrimination Training (Your Role as an RBT)

• Clear Sᴰ: Ensure the discriminative stimulus is clear, salient, and consistently presented.
• Salient Sᐞs: The Sᐞs should be different enough from the Sᴰ initially to make the discrimination easier.
  Gradually, they can be made more similar to teach finer discriminations (stimulus fading, covered in C-08, can be used here).
• Differential Reinforcement: This is the absolute cornerstone. Consistently reinforce the target behavior in the presence of the Sᴰ and withhold reinforcement (extinction) for that behavior in the presence of the Sᐞ.
• Error Correction: Have a clear procedure (from your supervisor) for what to do when the learner responds to the Sᐞ or makes an incorrect response in the presence of the Sᴰ (see C-10).
• Prompting and Fading: Use prompts initially to help the learner make the correct discrimination, then fade these prompts systematically (see C-08).
• Sufficient Trials: Discrimination learning often requires many trials and consistent practice.
• Varying Non-Critical Aspects: Once a basic discrimination is learned, vary irrelevant features of the Sᴰ and Sᐞs (e.g., different shades of red, different sizes of cat pictures) to promote generalization and ensure the learner is attending to the critical features, not irrelevant ones.

Discrimination Training in Action: Real-World Scenarios

• Receptive Colors (Simultaneous Discrimination):
  • RBT (Maria) & Client (Leo): Maria places a red block (Sᴰ for “red”) and a blue block (Sᐞ) on the table.
  • Sᴰ (Instruction): Maria says, “Leo, touch red.”
  • Response & Consequence:
    • If Leo touches the red block: Maria says, “Yes, red! Good job!” (SR+).
    • If Leo touches the blue block: Maria says nothing (or a neutral “Oops”), removes blocks briefly, then re-presents (often with a prompt for red on the next trial as part of error correction).
  • Progression: Maria might later add a yellow block as another Sᐞ, increasing the array size from 2 to 3.
• Expressive Labels (Tacts – Can involve Successive Discrimination):
  • RBT (David) & Client (Anya): David is teaching Anya to say “cup” when shown a cup and “book” when shown a book.
  • Trial 1 (Sᴰ = cup): David holds up a cup, asks “What is it?” Anya says “Cup.” David praises.
  • Trial 2 (Sᴰ = book): David holds up a book, asks “What is it?” Anya says “Book.” David praises.
  • Trial 3 (Sᴰ = cup, checking for discrimination): David holds up a cup, asks “What is it?” If Anya says “Book” (error), David would implement error correction (e.g., model “cup,” re-present). This ensures she’s discriminating between the cup and the book as cues for different vocal responses.
• Safety Skills (Discriminating a “Stop” Sign):
  • RBT (Chen) & Client (Sam): Chen uses picture cards in DTT. One card is a red stop sign (Sᴰ for saying “stop” or performing a “stop” action). Other cards are various irrelevant Sᐞs (e.g., a green “go” sign, a picture of a tree).
  • Sᴰ (Instruction): Chen shows the stop sign and asks, “What do you do?”
  • Response & Consequence: If Sam says “Stop,” Chen reinforces. If Chen shows the tree (Sᐞ) and Sam says “Stop,” no reinforcement for that response in the presence of the tree.
  • Generalization: Later, during a walk in the community (NET), Chen would point to a real stop sign and ask, “What do we do?” to ensure generalization of the discrimination to the natural environment.

Essential Vocabulary for Discrimination Training

• Discrimination: Responding differently to different stimuli.
• Discriminative Stimulus (Sᴰ): Signals availability of reinforcement for a specific response.
• S-delta (Sᐞ): Signals reinforcement is NOT available for a specific response.
• Stimulus Control: When a behavior reliably occurs in the presence of an Sᴰ but not an Sᐞ.
• Differential Reinforcement: Reinforcing a response in the presence of Sᴰ; withholding reinforcement for the same response in the presence of Sᐞ.
• Feature vs. Function: Discriminating based on physical features (e.g., color, shape) vs. discriminating based on what something does or is used for.
• Conditional Discrimination: A discrimination in which the reinforcement of a response to a stimulus depends on (is conditional upon) other stimuli (e.g., in matching-to-sample, the correct comparison choice depends on the sample).
• Concept Formation: Learning to discriminate based on a class of stimuli that share common properties (e.g., discriminating all “dogs” from all “cats,” even with novel examples). This involves generalization within a stimulus class and discrimination between stimulus classes.
• Stimulus Class: A group of stimuli that share common elements (formal, temporal, or functional) and all evoke the same response.
• Response Class: A group of responses with different topographies but all produce the same effect on the environment (i.e., serve the same function). (Less directly tied to stimulus discrimination but an important related concept).

Common Pitfalls in Discrimination Training

• Inconsistent Sᴰ or Sᐞ Presentation: Presenting stimuli unclearly, or inadvertently providing cues that help the client guess (e.g., always placing the correct item on the right).
• Insufficient Differential Reinforcement: Accidentally reinforcing responses in the presence of an Sᐞ, or failing to consistently reinforce responses in the presence of the Sᴰ. This makes it very hard for the learner to “get” the rule.
• Ineffective Prompting or Prompt Fading: Not providing enough help initially, or not fading prompts, leading to errors or prompt dependence.
• Poor Choice of Sᐞs (Too Similar or Too Different Initially): If Sᐞs are too similar to the Sᴰ at the start, the discrimination might be too hard.
  If they are always wildly different, the learner might not be learning the critical features of the Sᴰ. (Your supervisor will guide this).
• Not Enough Trials: Discrimination often takes many learning opportunities.
• “Side Bias” or “Position Bias”: The learner consistently picks an item based on its position (e.g., always picks the one on the left) rather than discriminating based on the stimulus itself. RBTs must vary positions of stimuli in an array.
• Reinforcing “Trying Hard” on an Error: While maintaining rapport is important, the specific response to an Sᐞ (or an incorrect response to an Sᴰ) should not receive the same reinforcement as a correct discrimination.
• Moving to More Complex Discriminations Too Quickly: Not ensuring mastery of simple discriminations (e.g., between 2 items) before moving to more complex ones (e.g., an array of 5 items).
• Failing to Check for Unintended Stimulus Control: Sometimes a learner might be responding based on an irrelevant feature (e.g., a tiny smudge on the “correct” card) rather than the intended feature (e.g., the color red). RBTs should be observant for this and report to their supervisor.

Discrimination training is fundamental to nearly all learning.

As an RBT, your precise implementation of these procedures, especially the consistent application of differential reinforcement, is vital for teaching clients to navigate their world effectively.

Understanding how to teach someone to respond to “red” but not “blue” is a microcosm of how we teach much more complex skills.

This provides a very thorough breakdown of C-07. We’ve covered the core concepts of Sᴰ, Sᐞ, stimulus control, the mechanism of differential reinforcement, and common procedures like simultaneous/successive discrimination and matching-to-sample.

Next in Section C is C-08: Use Prompt and Prompt Fading Procedures. This is intrinsically linked to DTT, NET, chaining, and discrimination training, basically all the teaching we do!