Discrete Trial Training (DTT) involves a structured, systematic approach to teaching new skills, typically broken down into five distinct steps that form a complete learning cycle.
Discrete Trial Training is a method commonly used in Applied Behavior Analysis (ABA) to teach skills in a focused and repetitive manner. Each "trial" is a single teaching opportunity, carefully structured to maximize learning. The five core steps of a DTT trial are:
1. Antecedent (or Stimulus)
The Antecedent, also known as the stimulus, is the instruction or cue that signals to the learner what is expected. This step "prepares the child for the task that comes next." It's the beginning of the teaching opportunity, designed to elicit a specific response from the learner.
- Purpose: To set the occasion for the desired behavior.
- Examples:
- A verbal instruction, such as "Touch your nose."
- Presenting a picture and asking, "What is this?"
- Holding up an object and saying, "Give me."
2. Prompt
A Prompt is any form of assistance provided to the learner after the antecedent to help them respond correctly. Prompts are used to ensure the learner makes the correct response, which allows for reinforcement and minimizes errors. The goal is to fade prompts as quickly as possible so the learner can respond independently.
- Purpose: To guide the learner to the correct response.
- Types of Prompts (examples):
- Physical Prompt: Gently guiding the learner's hand to touch their nose.
- Gestural Prompt: Pointing towards the correct answer.
- Verbal Prompt: Giving a sound or part of the word as a hint.
- Positional Prompt: Placing the correct item closer to the learner.
3. Child Response
The Child Response is the learner's behavior or action that occurs immediately after the antecedent and any given prompts. This is the skill or behavior that is being taught and observed. The response can be correct, incorrect, or no response at all.
- Purpose: To observe whether the learner has acquired the target skill.
- Examples:
- The child successfully touches their nose after the instruction.
- The child points to the correct picture when asked.
- The child hands over the requested object.
4. Consequence of Response
The Consequence of Response refers to what happens immediately after the child's response. This step is crucial for shaping behavior. For a correct response, a positive reinforcer (something the learner likes) is given, which increases the likelihood of the behavior happening again in the future. For an incorrect response or no response, a corrective procedure or no reinforcement is provided.
- Purpose: To strengthen desired behaviors and decrease undesired ones.
- Examples:
- For a correct response: "Great job!" accompanied by praise, a high-five, or a small edible treat.
- For an incorrect response: A neutral statement like "Try again," or restating the antecedent without reinforcement, sometimes followed by a more intrusive prompt to guide to the correct answer.
5. Intertrial Interval
The Intertrial Interval (ITI) is a brief pause between the end of one complete trial (after the consequence) and the beginning of the next. This short break allows the instructor to record data on the previous trial, reset the environment if necessary, and prepare for the next antecedent.
- Purpose: To allow for data collection, a quick reset, and to clear the "slate" for the next learning opportunity.
- Duration: Typically only a few seconds, ranging from 1-5 seconds.
These five steps work together in a cyclical fashion, providing clear, concise, and repeated learning opportunities that are highly effective for teaching a wide range of skills.
Summary Table of DTT Steps
| Step | Description | Example (Teaching 'Touch Nose') |
|---|---|---|
| 1. Antecedent/Stimulus | The cue or instruction that sets the occasion for the child's response. | Teacher says, "Touch your nose." |
| 2. Prompt | Any assistance given to help the child respond correctly. | Teacher gently guides the child's hand to their nose. |
| 3. Child Response | The child's action (or non-action) in response to the antecedent/prompt. | Child touches their nose. |
| 4. Consequence | What happens immediately after the child's response (reinforcement/correction). | Teacher says, "You touched your nose! Great job!" and gives a high-five. |
| 5. Intertrial Interval | A brief pause between the end of one trial and the beginning of the next. | A few seconds of pause, allowing the teacher to record data and prepare. |
