RBT Task List – Skill Acquisition (C-04)

Having laid the groundwork with understanding skill acquisition plans (C-01), preparing for sessions (C-02), and the critical use of reinforcement contingencies (C-03), we now move into one of the most well-known and structured teaching methodologies in ABA.

Let’s dive into a comprehensive exploration of:

C-04: Use Discrete-Trial Teaching Procedures

Discrete-Trial Teaching (DTT), also sometimes referred to as Discrete-Trial Training or Discrete-Trial Instruction (DTI), is a cornerstone of Applied Behavior Analysis.

It’s a highly structured, one-on-one teaching strategy used to teach a wide variety of skills. As an RBT, you’ll likely spend a significant amount of time implementing DTT, so a thorough understanding is absolutely crucial.

What Exactly is Discrete-Trial Teaching?

Discrete-Trial Teaching (DTT) is an instructional method characterized by its highly structured, systematic approach to teaching skills in simplified, distinct steps.

Each “trial” or teaching unit is “discrete,” meaning it has a clear beginning, a specific response from the learner, and a clear consequence delivered by the instructor, followed by a brief pause before the next trial begins.

This method breaks down complex skills into smaller, manageable components and provides repeated opportunities for the learner to practice and receive reinforcement.

DTT is often used for teaching new skills, especially foundational ones like:

• Imitation
• Receptive language (e.g., following directions, identifying objects)
• Expressive language (e.g., labeling, answering questions)
• Early academic skills

The structure of DTT allows for high rates of responding and reinforcement, which can lead to rapid skill acquisition for many learners.

The RBT’s role is to implement DTT procedures with precision and fidelity as outlined in the client’s skill acquisition plan.

The Anatomy of a Discrete Trial: The 5 Key Parts

A single discrete trial typically consists of five key parts, which flow in a specific sequence. You might hear the acronym “SD-R-SR-ITI” used to remember the core components (though prompt is often included in the explanation):

• Discriminative Stimulus (Sᴰ) / Antecedent:
  • What it is: This is the instruction, question, or cue delivered by the RBT. It signals to the learner that reinforcement is available for a specific target response.
    The Sᴰ should be clear, concise, and delivered consistently.
  • Example: “Point to red,” “What is this?” (while showing an object), “Do this” (while modeling an action).
  • RBT’s Role: Deliver the Sᴰ exactly as specified in the skill acquisition plan. Ensure the client is attending before delivering it, and typically present it only once per trial (unless the error correction procedure involves re-presenting it).
• Prompt (P) (If needed):
  • What it is: This is any assistance provided by the RBT after the Sᴰ but before or during the client’s response.
    The purpose of a prompt is to increase the likelihood of a correct response, especially when the learner is not yet able to respond independently.
  • Types of Prompts: Verbal, gestural, model, physical (full or partial), visual, positional. (We’ll cover prompts in much more detail in C-08).
  • RBT’s Role: Deliver prompts as specified in the skill acquisition plan (e.g., type of prompt, timing, intensity) and systematically fade them as the learner becomes more proficient.
• Response (R) / Behavior:
  • What it is: This is the learner’s behavior that occurs after the Sᴰ (and prompt, if one was used). This is the skill being targeted.
  • Types of Responses: Responses can be correct (either independent or prompted), incorrect, or the client might not respond at all.
  • Response Latency: The skill acquisition plan may specify an acceptable time window for the response (e.g., respond within 3-5 seconds).
  • RBT’s Role: Objectively observe and evaluate the client’s response based on the operational definition of the target skill in the plan.
• Consequence (SR / Reinforcement or Error Correction):
  • What it is: This is what happens immediately after the learner’s response, and it’s determined by the nature of that response.
    • For a Correct Response: Positive reinforcement (SR+) is delivered (e.g., praise, token, edible, brief access to a toy). The type and schedule of reinforcement are specified in the skill acquisition plan (as discussed in C-03).
    • For an Incorrect Response or No Response: An error correction procedure is implemented, as specified in the plan.
      This might involve providing corrective feedback, re-presenting the Sᴰ with a more intrusive prompt, or simply moving to the next trial without reinforcement for the error. (More on error correction in C-10).
  • RBT’s Role: Deliver the appropriate consequence immediately and contingently. If delivering reinforcement, it should be enthusiastic and paired with social praise.
    If implementing error correction, it should be done neutrally and efficiently.
• Inter-Trial Interval (ITI):
  • What it is: This is a brief pause (typically 1-5 seconds) after the consequence has been delivered and before the next Sᴰ is presented.
  • Purpose:
    • Clearly separates one trial from the next.
    • Allows the learner time to consume an edible reinforcer or briefly engage with a tangible reinforcer.
    • Gives the RBT time to record data, reset materials for the next trial, and prepare to deliver the next Sᴰ.
  • RBT’s Role: Maintain an appropriate ITI. It should be long enough for the above purposes but not so long that the learner loses attention or the teaching momentum is lost.
    Avoid engaging in excessive conversation or interaction during the ITI unless it’s part of a planned “pairing” or NET-style interspersal.

Key Characteristics and How to Implement DTT

DTT has several distinct characteristics and implementation considerations:

• Structured Setting: Often conducted at a table in a distraction-minimized environment, but can be adapted.
• One-on-One Instruction: Typically delivered by one RBT to one client.
• Clear Instructions (Sᴰs): RBTs must use consistent and concise Sᴰs.
• Systematic Prompting and Fading: Prompts are used to ensure success and then systematically removed as the learner demonstrates independence (more in C-08).
• Immediate Reinforcement: Correct responses are reinforced immediately to strengthen the Sᴰ-R connection.
• Data Collection: Data are typically collected on every trial (or a subset of trials, like first trial probes) to monitor progress.
• Repetition and Practice: DTT provides many opportunities for the learner to practice the target skill.
• Breaking Down Skills: Complex skills are often broken down into smaller, teachable components.
• Errorless Learning (Often a Goal): Procedures are often designed to minimize errors, especially in early learning, by using effective prompting.
• Mass Trial vs. Random Rotation/Interspersed Trials:
  • Mass Trial (MT): Presenting the same Sᴰ repeatedly for a set number of trials (e.g., “Touch red,” “Touch red,” “Touch red”). Often used when first introducing a new skill.
  • Random Rotation (RR) / Interspersed Trials: Presenting different S^Ds (for different skills or different targets within the same skill) in a mixed or random order. This helps with discrimination and maintenance.
    • Example of RR for receptive colors: “Touch red,” “Touch blue,” “Touch red,” “Touch green,” “Touch blue.”
    • Example of interspersing mastered skills (maintenance) with acquisition targets: “Touch red” (acquisition), “Clap hands” (mastered), “What’s your name?” (mastered), “Touch red” (acquisition). This is often called “mixing and varying” trials.
  • The skill acquisition plan will specify which format to use.

DTT in Action: A Scenario with Sarah and Ben

Let’s see how this looks in a real-world example:

• RBT: Sarah
• Client: Ben (5 years old)
• Target Skill (from plan): Receptive identification of “cat” from an array of 3 pictures (cat, dog, fish).
• Skill Acquisition Plan Specifies:
  • Sᴰ: “Point to cat.”
  • Materials: Picture cards of cat, dog, fish. Small crackers as reinforcers.
  • Prompt: If no response or error, use a full gestural prompt (point to cat) on the next trial (errorless learning approach).
  • Reinforcement: CRF (praise + 1 cracker) for independent correct. Praise only for prompted correct.
  • Error Correction: For error, say nothing, remove cards briefly, re-present array and Sᴰ with immediate prompt.
  • ITI: ~3 seconds.
  • Data: +/- for independent correct, “P” for prompted.

A Few Trials:

1. Trial 1:
   • Sarah arranges cards (cat, dog, fish). Ensures Ben is attending.
   • Sᴰ: Sarah says clearly, “Ben, point to cat.”
   • Response: Ben points to the picture of the cat within 2 seconds.
   • Consequence (SR+): Sarah immediately says, “Awesome, Ben, that is the cat!” and gives him a cracker.
   • Data: Sarah marks “+” on her data sheet.
   • ITI: Sarah waits ~3 seconds, perhaps while Ben eats the cracker, then prepares for the next trial (rearranges card positions).
2. Trial 2:
   • Sarah rearranges cards.
   • Sᴰ: “Ben, point to cat.”
   • Response: Ben points to the picture of the dog. (Incorrect)
   • Consequence (Error Correction): Sarah says nothing, neutrally removes the cards for a second, then re-presents the array.
   • Sᴰ (Re-presentation with Prompt): “Ben, point to cat” (as she says “cat,” she subtly points to the cat card herself – gestural prompt).
   • Response (Prompted): Ben points to the cat.
   • Consequence (for prompted correct): Sarah says, “Good pointing, Ben.” (No cracker, as per plan).
   • Data: Sarah marks “P” on her data sheet.
   • ITI: Sarah waits ~3 seconds, rearranges cards.
3. Trial 3 (and so on…): The process continues.

When to Use DTT (And When to Consider Other Methods)

DTT is a powerful technique, but it’s important to know its strengths and when other approaches might be complementary:

• Strengths/Good For:
  • Teaching new, discrete skills.
  • Learners who benefit from structure and repetition.
  • Building foundational skills (imitation, receptive/expressive language basics).
  • Situations where high rates of practice are needed.
  • Skills that can be easily broken down.
• Potential Challenges/Considerations (and why NET or other methods might be complementary):
  • Generalization: Skills learned in highly structured DTT might not always generalize easily to natural environments without specific planning for generalization (more in C-09).
  • Prompt Dependence: If prompts are not faded effectively, learners can become reliant on them.
  • Motivation: If not done well (e.g., reinforcers not potent, pace too slow/fast, lack of “fun”), DTT can sometimes seem robotic or lead to escape/avoidance behaviors. Pairing DTT with fun and varying reinforcers is key.
  • Spontaneity: DTT is less focused on spontaneous use of skills in natural contexts compared to Natural Environment Teaching (NET).
  • RBTs often use DTT in conjunction with NET to address these considerations.

Key DTT Vocabulary

• Discrete Trial: A single cycle of Sᴰ-Prompt(if any)-Response-Consequence-ITI.
• Trial: Synonymous with discrete trial.
• Discriminative Stimulus (Sᴰ): The instruction/cue.
• Response (R): The learner’s behavior.
• Consequence (SR/Error Correction): Outcome following the response.
• Inter-Trial Interval (ITI): Pause between trials.
• Mass Trial (MT): Repeating the same Sᴰ across trials.
• Random Rotation (RR): Mixing different Sᴰs.
• Distractor Trial/Item: Presenting known/mastered items or instructions interspersed with acquisition targets to ensure discrimination and maintain engagement.
• Expanded Trials: Gradually increasing the number of distractor trials between presentations of the target Sᴰ.
• Errorless Learning: Using prompts to ensure the learner makes correct responses from the outset, minimizing errors. Prompts are then systematically faded.
• Maintenance Trials: Periodically re-presenting mastered skills to ensure they are retained.
• Probe Trial: A trial delivered without prompts (often the first trial of a session for a target) to assess independent responding.

Common Mistakes to Avoid When Implementing DTT

Be mindful of these common errors:

• Inconsistent Sᴰ Delivery: Varying the wording or tone of the Sᴰ, or providing it when the client isn’t attending.
• Delayed or Ineffective Reinforcement: Not delivering reinforcement immediately, or using items that aren’t actually reinforcing for the client at that moment.
• Incorrect Prompting: Using the wrong type of prompt, prompting too quickly (not giving the client a chance to respond independently), or failing to fade prompts systematically.
• Faulty Error Correction: Reinforcing errors inadvertently (e.g., with attention), or using an overly punitive or lengthy error correction that disrupts the flow.
• ITI Too Short or Too Long: Too short doesn’t allow data recording or material reset; too long can lead to loss of momentum or client disengagement.
• Lack of Enthusiasm/Pairing: Delivering trials robotically without making the interaction positive and engaging.
• Failure to Vary Reinforcers: Leading to satiation.
• Not Collecting Data Accurately or on Every Required Trial: Missing data points or incorrectly scoring responses.
• Sticking to Mass Trials for Too Long: Not moving to random rotation or interspersing mastered skills, which can hinder discrimination and generalization.
• Not Following the Specific Protocol: Each DTT program for each skill is individualized. The RBT cannot assume the procedure for teaching “red” is identical to teaching “shoe.”

Discrete-Trial Teaching is a powerful tool when implemented with precision and care. Your ability as an RBT to consistently deliver each component of the discrete trial as outlined in the skill acquisition plan is fundamental to your client’s learning of new skills.

Given its structured nature, DTT scenarios are common in practice exams.

This provides a very comprehensive look at C-04: Discrete-Trial Teaching Procedures. We’ve covered its components, characteristics, common implementation formats, and potential pitfalls.

Next up in our series is C-05: Use Naturalistic Teaching Procedures (e.g., Incidental Teaching). This offers a nice contrast to DTT.