What Is Discrete Trial
Discrete trial training (DTT) is a structured teaching method used in applied behavior analysis (ABA) that breaks learning into isolated, repeatable units. Each trial has three distinct parts: a clear instruction from the teacher or parent, an opportunity for the child to respond, and an immediate consequence (usually reinforcement or corrective feedback). The trial then ends, and a new one begins after a brief pause.
Unlike learning that happens naturally throughout the day, discrete trials isolate one skill at a time in a controlled setting. A parent might use discrete trials to teach a child to make eye contact, follow a one-step direction, or identify colors. The repetition and predictability help children with developmental delays, autism spectrum disorder, or sensory processing challenges learn skills that don't come naturally through everyday exposure.
How It Works
A discrete trial follows this basic sequence:
- Instruction: You deliver a clear, specific request. Example: "Touch your nose" or "Say 'hello.'"
- Response window: You wait 3 to 5 seconds for the child to respond. If the child doesn't respond independently, you may provide a prompt (a gesture, model, or physical guide) to help them succeed.
- Consequence: You provide immediate feedback. Correct responses receive reinforcement (praise, preferred snack, sticker, sensory reward). Incorrect responses receive a brief correction and no reinforcement.
- Intertrial interval: You pause for 2 to 10 seconds before starting the next trial, clearing the expectation for the previous instruction.
Most ABA programs using discrete trials run 15 to 40 trials per session, depending on the child's age and tolerance. Young children (ages 2 to 4) typically tolerate shorter sessions with more frequent breaks. Research shows that massed practice (many trials in one session) produces faster skill acquisition than distributed practice, though combining both approaches often works best for emotional regulation.
When to Use Discrete Trials
Discrete trials work best for teaching concrete, measurable skills that don't require complex social context:
- Following instructions ("sit down," "give me five")
- Labeling objects or people ("point to the dog")
- Matching or sorting tasks
- Speech and language basics (sounds, words, simple sentences)
- Self-care routines (washing hands, putting on shoes)
- Managing sensory input (tolerating transitions, waiting for preferred items)
For children with sensory sensitivities, discrete trials can help teach tolerance for uncomfortable sensations in small, manageable doses. A child who avoids loud noises might do five 30-second trials listening to a moderately loud noise with a preferred toy nearby as reinforcement.
Discrete Trials vs. Natural Learning
Discrete trials contrast with natural environment teaching, which embeds learning into everyday routines and play. Most comprehensive ABA programs use both. Discrete trials build foundational skills quickly in a distraction-free setting. Natural environment teaching then helps the child use those skills in real-world contexts like mealtimes, outdoor play, and social interactions. This combination helps prevent "splinter skills" where children master a skill in therapy but fail to use it at home or school.
Common Questions
Aren't discrete trials boring or robotic for kids? Not when done correctly. Effective discrete trial sessions use highly preferred rewards and vary the activities to keep engagement high. The structure actually reduces frustration for many children because expectations are clear and success is frequent. Sessions should feel like play, not punishment. If a child consistently resists, the reinforcer may not be strong enough, the skill is too difficult, or the child needs a break.
How many trials should we do at home? Most parents aren't expected to run formal discrete trial sessions like therapists do. Instead, aim for brief, informal practice during natural routines. If your child's therapist assigns specific targets (like expanding vocabulary or following directions), you might do 5 to 10 trials during mealtime or bath time, keeping sessions under 10 minutes to prevent burnout. Always prioritize your child's emotional state over hitting a trial count.
What if my child has sensory sensitivities that make them refuse discrete trials? Sensory issues often drive avoidance behaviors during structured tasks. Work with your child's therapist to identify the specific sensory trigger (auditory, visual, proprioceptive). You may need to modify the environment (dim lighting, quieter space, fidget toy available) or use powerful sensory rewards (deep pressure, preferred textures) to build tolerance. Sometimes shorter, more frequent sessions work better than longer ones.
Related Concepts
- Natural Environment Teaching combines discrete trial skills into everyday routines.
- ABA (Applied Behavior Analysis) is the broader framework that uses discrete trials as a teaching tool.
- Reinforcement is what makes discrete trials effective by motivating correct responses.