Skip to content

What is Discrimination Training in ABA & Why Do We Teach It?

discrimination training

Discrimination training is a fundamental concept in Applied Behavior Analysis. It’s crucial in helping individuals with developmental disabilities acquire new skills, reduce problem behavior, and promote independence.

In this post, we’ll explore the concept of discrimination training as it applies to language, its importance in ABA, and strategies for effective implementation.

What is Discrimination Training?

This involves teaching individuals to differentiate between two or more stimuli. Based on the principles of reinforcement, correct responses to one stimulus are reinforced while incorrect responses to another stimulus are not.

For example, if you put out 2-3 objects and ask, “Which one is the banana?” the learner engages in discrimination training when he chooses the banana and not the options. Individuals learn to respond appropriately to specific cues or stimuli by teaching discrimination.

Types of Stimuli in Discrimination Training

In discrimination training, different types of stimuli are used to teach individuals to differentiate between them. One type of stimulus is the discriminative stimulus (SD), which signals the availability of reinforcement for specific responses. Another type is the stimulus delta (S delta), which indicates that reinforcement will not be provided for a particular response.

While the goal of discrimination training is for individuals to learn to respond only to the SD and not the S delta, it’s important to note that this may require additional training and practice. With proper instruction and reinforcement, individuals can develop the ability to discriminate between the SD and the S delta, responding appropriately to each stimulus.

Discrimination Training Procedures

There are several procedures used in discrimination training within ABA:

Simple Discrimination

This involves teaching individuals to differentiate between two stimuli. The most common ABA program teaching simple discrimination is receptive labels. For example, a child may be taught to identify red from a set of different-colored objects.

Conditional Discrimination

This procedure teaches discrimination among multiple stimuli using conditional relationships. For instance, a child may learn to match pictures of animals to their corresponding sounds.

Stimulus Fading

This technique involves gradually modifying the stimuli to ensure generalization. For instance, a child may initially learn to recognize a banana in a specific shape and color, but the stimuli can be faded to include bananas of different sizes and colors.

What’s the Importance of Discrimination Training in ABA?

Skill Acquisition

Discrimination training is crucial for students to acquire and generalize new skills. Teaching them to discriminate between stimuli allows them to learn language, academics, and social skills effectively.

Reducing Unwanted Behavior

Discrimination training also plays a significant role in reducing unwanted behavior. By teaching individuals alternative, appropriate responses, they can replace problem behaviors with more adaptive behaviors.

Precursor to Functional Communication

Functional communication training – a subset of discrimination training – teaches learners to communicate their needs and wants effectively. Doing so can minimize problem behaviors related to frustration or lack of communication skills.

When to Teach Discrimination Training

Discrimination training isn’t something we dive into headfirst. It’s typically used during discrete trial teaching (DTT). However, before beginning DTT, specific prerequisite skills should be established first.

Picture this: I was just hired as Josie’s ABA therapist, and I had just met her. She doesn’t know me at all. I immediately walk into her house and set out my flashcards ready to get to work.

First things, first! A relationship needs to be established. Josie needs to learn that I am a source of joy and comfort, her trusted companion, providing many preferred activities such as warm hugs, playful tickles, delicious snacks, and exciting playtime.

After pairing, here are some other prerequisite skills needed to embark on this journey of discrimination training:

  • Instructional Motivation: Establishing a mutually beneficial relationship where the student learns first — I do something for you, then I get something fun.
  • Joint Attention: This is the magical moment when both of us are captivated by the same object, creating a shared experience.
  • Follows a Point: If I point towards an object, will Josie’s gaze follow? This simple act can be a powerful tool in our learning process.
  • Basic One-Step Instructions: Can Josie respond to simple commands like “come here” or “sit down”? Following these basic instructions is a stepping stone towards more complex tasks.

How To Teach Discrimination Training

1. Start with Neutral Items

Let’s discuss discrimination training specifically related to teaching receptive labels (e.g., “Show me ball”). It’s essential to start discrimination training with functional, yet neutral items without inherent meaning to the individual.

This approach reduces the chances of the individual having a strong preference for one item over the other. ABA professionals can use real items instead of flashcards to establish a more realistic link between picture-object correspondence and avoid any confusion.

2. Begin with One Item

Starting with only one item helps make discrimination training easier as the individual can focus on one object at a time. ABA professionals can hold out their hand and say the name of the item or phrase, such as, “Give me [item].” Avoiding filler words helps the client to better distinguish between different stimuli and avoid any misinterpretations.

3. Gradually Increase the Number of Items Presented

As the learner masters discrimination between one item and non-preferred item(s), ABA professionals should start introducing more challenging scenarios. Gradually increasing to two preferred items can prove a little more difficult, so the items should be dissimilar.

Introducing two unrelated items, like a ball and a shoe, can prove more effective in distinguishing between each item. ABA therapists can continue to add more items into the mix until the client can distinguish between the items.

4. Focus on Mastery

ABA professionals should prioritize mastery before introducing a new item to the client. Mastery means that the client can consistently discriminate between the target object and non-target objects at a mastery rate of 80-100%.

Continuing to introduce new stimuli while the individual is still struggling can lead to frustration and confusion. For example, if the client can only discriminate between one or two items at a mastery rate of 50%, it may be too soon to move on to new targets.

5. Be Patient and Persistent

Discrimination training can be a long process. It requires patience, persistence, and repetition. It’s important to allow the individual enough time to understand and practice the task at their own pace without rushing the process. ABA professionals should always remain persistent in reinforcing the correct discriminations and avoid negative reinforcements.


Discrimination training is a fundamental component of ABA and has significant implications for individuals. By understanding the process of discrimination training, its importance in skill acquisition, reducing problem behavior, and enhancing independence, ABA professionals can positively impact their clients’ lives. By implementing effective strategies and considering individual needs, discrimination training can unlock new opportunities for growth and independence.

3 thoughts on “What is Discrimination Training in ABA & Why Do We Teach It?”

  1. Hi,
    Thank you for the nice quick blogpost as well as the video on discrimination training. I appreciate it as a basic way to explain to both my paraprofessionals as well as my students parents what discrimination training is and why we do it. I would love to hear what you have done when adding two mastered items together just doesn’t seem to work. I know that might be a long path to go down, but I feel like I have tried everything under the sun for one of my students that I have currently and although he can master many targets in a field of 3 when two items have never been targeted before, the minute I mix in two targeted items with one neutral he bombs. (not very technical language).

    1. Hi Julia! The way we would teach it is once a student has 2 receptive items mastered with neutral distractors each, we would do a random rotation step with the 2 mastered targets. It would be broken down like this:
      a. Array of 3 – both target items + 1 distractor – Ask for Target 1
      b. Array of 3 – both target items + 1 distractor – Ask for Target 2
      c. Array of 3 – both target items + 1 distractor – Rotate between asking for Target 1 and Target 2
      Then, teach a 3rd target separately. When that’s mastered, introduce a random rotation step with targets 1, 2, and 3

  2. Pingback: Following 1-Step Instructions - How to ABA

Leave a Reply

Your email address will not be published. Required fields are marked *

Captcha loading...