When analyzing human behavior, behavior analysts like to know what behavior was exhibited, what happened before and after the behavior, when and why the behavior occurred, and most importantly, how we can manipulate the consequences of that behavior so that the behavior increase or decrease in the future. What behavior analysts enjoy the most is understanding under which conditions a behavior occurs, or more so, the ABCs of each occurrence!

So let’s go in depth…Behavior Analysts explain behaviors by the three-term contingency, or the ABCs of behavior analysis, as we refer to it, which consists of:

  • A= Antecedent- The events/actions that occur immediately before a behavior
  • B= Behavior- What the person does 
  • C= Consequence- The actions/responses that immediately follow the behavior

To facilitate your understanding of the ABC contingency, let’s explain it in technical terms: the ABC is a three-term contingency which outlines that in the presence of an antecedent stimulus, the behavior occurs. The consequence provided then strengthens the antecedent-behavior relationship and makes a behavior less likely/more likely to occur in the future in the presence of that antecedent. 

The purpose of this blog post will be to explain the basics of the three-term contingency and how important it is in understanding particular behaviors. Our next blog post will go in-depth as to how you can manipulate antecedents and consequences to predict the occurrence of a particular behavior. 

So let’s get started with the ABC model…

  • What is an antecedent?
    • Definition: An antecedent is an environmental condition or stimulus change existing or occurring prior to a behavior of interest. 
    • When identifying the antecedents, it’s important to consider the following questions:
      • Where does the behavior occur?
      • When does the behavior occur?
      • With whom does the behavior occur?
      • What do other people say or do immediately before the behavior occurs?
      • What activities or events precede the behavior?
      • What are the Setting Events? Are there specific individuals present, proximity of others, environmental conditions (lighting, noise level, etc), changes in medicine, family routine changes, current health status, and anything that could affect the person exhibiting a particular behavior?
    • Why are antecedents important? In order to understand and modify behaviors, it’s important to know under what conditions a behavior occurs. Once we understand the antecedents of a particular behavior and we know when a behavior has been reinforced or punished (the consequences), we can predict the situations in which the behavior will occur in the future.
  • What is a behavior?
    • Definition: behavior is anything that a person does. Behavior can be determined by applying the Dead Man’s test: “If a dead man can do it, it isn’t behavior. And if a dead man can’t do it, then it is behavior!”
    • It is important to record as much information about the behavior of concern and have the operational definition of the target behavior- describing the behavior as clearly and concisely as possible (i.e., rather than saying ‘Joe exhibits aggression’, you should say: ‘Joe’s aggression is defined as any instance in which Joe’s hands, feet, body, or objects come in contact with another person. Examples of Joe’s aggression: kicking a peer, hitting a peer with an open fist, or pinching a peer’s leg.’)
  • What is a consequence?
    • Definition: A consequence is a stimulus change that follows a behavior of interest. In layman’s terms, the consequences are the events that happen to the person immediately following the behavior. 
    • Reinforcement: When a behavior is followed closely in time by a stimulus event and as a result the future frequency of that type of behavior increases in similar conditions. 
      • Positive Reinforcement: When a behavior is followed immediately by the presentation of a stimilus that increases the future frequency of the behavior in similar conditions. 
      • Negative Reinforcement: When a behavior is followed immediately by the removal of a stimilus that decreases the future frequency of the behavior in similar conditions. 
    • Punishment: When a behavior is followed closely in time by a stimulus event and as a result the future frequency of that type of behavior decreases in similar conditions. 
      • Positive Punishment: A behavior is followed immediately by the presentation of a stimulus that increases the future frequency of the behavior in smilar conditions. 
      • Negative Punishment: A behavior is followed immediately by the removal of a stimulus that decreases the future frequency of the behavior in smilar conditions. 
    • In layman’s terms: Behaviors followed by pleasant consequences are more likely to occur in the future. Behaviors that are not followed by pleasant consequences are less likely to occur in the future. 
    • Behaviors are generally maintained by these general types of consequences
      • Attention
      • Escape or Avoidance of an aversive event
      • Tangible rewards (play, candy, beverage, toy, etc.)
      • Automatic reinforcement

What does this mean for me? We have provided you with the basic foundations of the ABC model. We hope that this information will guide you in understanding how, when, and why behaviors occur by examining antecedents and consequences. We can often change behaviors by changing what we do immediately before (antecedents) and immediately after (consequences) a behavior occurs. 

Our next blog post will go in-depth as to how you can manipulate antecedents and consequences to predict the occurrence of a particular behavior and will include several examples of the ABC model, so stay tuned!!!

*Definitions were derived from Applied Behavior Analysis by Cooper, Heron, & Heward, 2007.