The ABC’s of ABA

Understanding the True Definitions of ABA Therapy

Children receiving ABA therapy together.

What is ABA?

Applied Behavior Analysis (ABA) is a scientific approach to behavior and learning used primarily as therapy for individuals with Autism Spectrum Disorder (ASD). ABA pays particular attention to how the environment and external stimuli affect a child. By focusing on the interaction between the environment and behaviors, ABA can be used for five main purposes:

  • To teach new skills, like reading or brushing teeth.
  • To increase behaviors, such as making eye contact.
  • To maintain behaviors, such as sight-reading words previously learned. 
  • To generalize behaviors across environments and situations.
  • To reduce the frequency of challenging behaviors, such as disruptive vocalizations or running away (eloping).

The goal of ABA is to increase the frequency of behaviors conducive to helping a child thrive and function in a wide range of environments through their ability to communicate, socialize and learn. Those behaviors include academic, social, communicative and daily living skills. In other words, ABA attempts to increase the quality of life of its subjects by developing within them the skills and habits necessary for learning, communicating and daily living. Practitioners of ABA (BCBAs and RBTs) use existing research to introduce behavioral interventions that encourage these behaviors.

It may be helpful to examine each part of Applied Behavior Analysis to get a better understanding of the sum of the parts.


‘Applied’ simply means that the behaviors we are trying to increase the frequency of are used in daily life. These behaviors are not lofty and theoretical; they are practical and useful. The purpose of ABA is to improve the quality of life of its subjects. Common examples of practical behaviors include brushing teeth, crossing the street safely and successfully using the toilet.


‘Behavior’ is whatever a person does. It is observable and measurable (more on that in a moment). Many times, the term ‘behaviors’ is used to refer to the group of maladaptive behaviors a particular individual exhibits, but properly speaking, positive behaviors are also behaviors. Screaming, making eye contact, eloping, asking before opening doors, reading quietly, biting self or others, jumping up and down are all examples of behaviors. Treatment plans often aim to increase the frequency of some behaviors, maintain others, and minimize those that are detrimental to a child’s ability to thrive. 

It is also important to remember where behaviors fit within the context of their environment. This relationship can be summed up with the acronym A-B-C: antecedent, behavior and consequence. 

  • Antecedents are the environment and events that precede a particular behavior. Consequences are what happen after a behavior. For example, a parent tells their child that it is time to brush their teeth. The child begins to cry and throw a tantrum. Any attempt to get the child to stop and brush their teeth is fruitless. The parent gives in and lets the child get away with not brushing their teeth ‘just this once’. In this example, telling the child that it’s time to brush their teeth is the antecedent. The action is crying and throwing a tantrum. The result is the child not having to brush their teeth that night. The example illustrates the importance of the consequences of behaviors in ABA. We only have so much control over what happens before a behavior (the antecedent), but we often are much more able to control the consequences of actions. In the case above, the child was able to avoid the behavior the parent wanted them to do (brush their teeth) by throwing a temper tantrum. This makes them more likely to throw tantrums when that antecedent shows itself again. In other cases, teachers or parents might mistakenly give attention to a child which could increase the frequency of an undesired behavior.
  • Behavior, as discussed, is what a person does. The emphasis here is that behaviors do not happen in isolation; there is an environment that surrounds people and affects the way they behave. When we analyze behaviors, we need to make connections between the antecedents and what a patient does.
  • Consequences generally take two forms: positive or negative reinforcements. A reinforcer is anything that increases the likelihood or frequency of a behavior when given after that behavior. Positive reinforcers often include allowing the subject to do something they like or giving them a favorite food item or toy. Negative reinforcement means removing something aversive or negative from the presence of the patient. It does not mean adding something painful in response to particular behaviors; punishment is not part of ABA therapy.


By clearly defining certain behaviors and consistently applying behavioral interventions, BCBAs and RBTs are able to collect detailed data regarding the frequency of behaviors outlined in a child’s treatment plan. The frequency of these behaviors should change over time, either increasing or decreasing depending on the goals of the parents. If the frequency is not changing, or changing in the wrong direction, BCBAs make changes to the initial plan. 

One common form of ABA therapy that allows for analysis is Discrete Trial Training (DTT). During DTT, the therapist gives an instruction. The client then gives a response, after which there is a consequence. Finally, there is an inter-trial interval. For example, an RBT might ask a child to put their finger on their nose (instruction). The child either puts their finger on their nose or does not (the response). The therapist then has a planned response for each situation (the consequence). For instance, if the child gets it right and puts their finger on their nose, the RBT could say “Good job!” and give them a high-five. Otherwise, they might say “not quite. This is your nose” pointing to their nose. Then there is some amount of time before the next discrete trial, during which the therapist records the result of that trial, which will be used later for analysis.

Applied Behavior Analysis examines connections between environments, behaviors and consequences. Practitioners of ABA are hyper-focused on how these conditions shape behavior and how changing them can affect habits that help an individual thrive and function better in a variety of environments and situations. While ABA is commonly administered to people with developmental disabilities, it has principles that can be applied to everyone’s lives and relationships.


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