Antecedent: A Specific Meaning for Analyzing Difficult Behaviors

The Antecedent precedes the behavior. Getty Images - Pedro Blanco

In preparing a functional behavior analysis, special educators, behavior specialists and psychologists use an acronym, ABC, to understand a target behavior. The A stands for antecedent, the B for behavior, and the C for consequence. ABC is a fundamental concept for those working with children, particularly students with special needs.

Antecedent Definition

To understand the definition of ABC, it's important to learn the meaning of each of its component parts. Project Ideal explains that antecedents are events or environments that trigger a behavior. The website, published by the Texas Council for Developmental Disabilities, further explains that the behavior is an action that is both observable and measurable that is generally provoked or induced by the antecedent. The consequence, then, is the response to the student’s behavior, generally by the teacher, counselor, or school psychologist.

Put in more basic terms, the antecedent involves something that is said to the student, something the student observes, or, often, a situation in which the student is placed. Any of these things can then evoke a behavior by the student, such as acting out, throwing a tantrum, screaming, or just shutting down. The consequence is not necessarily—or even preferably—a punishment. Instead, a consequence is what educators or others impose on the student after the behavior. Education and behavior experts note that the best consequence is one that redirects, rather than punishes.

The ABC concept is important because it causes educators, counselors, and others involved to loop back to the antecedent and try to determine what in the environment or situation might have provoked the behavior. Since the behavior must be observable and measurable, using the ABC concept takes emotion out of the equation. In essence, it is similar to a math equation:

A leads to B which then evokes C


A > B = C.

Questions to Gather Information About the Antecedent

The ABC principal involves collecting—or asking—the right questions as to what might have provoked the behavior. In other words, you need to try to determine what antecedent(s) led to the behavior. Questions might include:

Where does the target behavior occur? This addresses the impact of the environment on the antecedent or setting event. Does it only happen at home? Does it happen in public? Does it only happen in a specific place and not in the other? If the antecedent is school and not home, it probably reflects that little or no demand is put on the child in the other environment. Sometimes, if a student has been abused in a school or residential facility, and the environment looks very much like that setting, the student's behavior might actually be reactive: a means of protecting himself. 

When does the target behavior occur? Does it happen mostly at a certain time of days? Is it perhaps related to the child being tired after working hard to meet demands (near the end of the day)? Could it be related to hunger (at 11 a.m. before lunch)? Could it be related to anxiety about bedtime if it happens in the evening?

Who is present when the target behavior occurs? It is possible for certain people or people dressed in a certain way may trigger a behavior. Perhaps it's people in white coats. If the child has been frightened or undergone a painful procedure at a doctor's office, she may be anticipating a repeat of the experience. Often students, especially students with developmental disabilities, are frightened by people in uniforms if their parents have had to call the police to get assistance with a particularly violent meltdown.

Does something happen just before the target behavior? Is there an event that triggers the behavior? A student may respond in fear to something that happens, or even if a peer moves into his space. All of these things may contribute to the "setting event" or antecedent to the event.

How to Use Antecedents in an Educational Setting

An example of ABC in a real-life classroom setting might be as follows:

In the morning upon arrival, when presented with her work folder (antecedent), Sonia throws herself out of her wheelchair (behavior). Clearly, the antecedent is being presented with the work folder, and it happens at the beginning of the day. Knowing that giving Sonia a work folder in the morning provokes exactly the same response every day, it would make sense to create a different antecedent in the morning for Sonia, instead of enforcing a punitive consequence. Instead of giving her a work folder the minute she comes into the classroom, the teacher, or education team, might ask: What does Sonia enjoy?

Suppose Sonia enjoys social interaction, the simple give-and-take of simple dialogue between a teacher, paraprofessionals, and the student. In that case, to create a better outcome, the educators would present Sonia with different start-of-the-day activity, such as a short, social talk with the teacher and staff. They might ask Sonia what she did last night, what she had for dinner, or even what she plans to do over the weekend.

Only after this five-minute discussion would the staff offer Sonia her work folder. If she still exhibits the same behavior—throwing herself out of her wheelchair—the staff would again do an ABC analysis. If Sonia simply doesn't react well to an offer of work first thing in the morning, the staff would try another antecedent, such as changing the setting. Perhaps a brief morning excursion outside on the playground might be the best way to start Sonia's day. Or, giving Sonia her work folder later in the morning, after a talk, excursion outside, or even a song, might lead to a better outcome.

As noted, the key to using ABC is taking emotion out of the equation. Rather than a knee-jerk reaction to Sonia's behavior, the staff tries to determine what was the antecedent, what observable behavior occurred, and what consequence was enforced. By manipulating (or changing) the antecedent, the hope is that the student will exhibit a different, more positive behavior, negating the need for a "punitive" consequence.