The Four Functions of Behavior Explained

Blain Hockridge
Autism Case Supervisor

There is a certain image that comes to mind when thinking of a child with autism who exhibits severe problem behavior. It conjures images of physical aggression, screaming, spitting, scratching and a child unwilling to budge an inch. Many people have seen parents in public places, such as supermarkets or restaurants, attempt to reason with a child in the middle of a tantrum. From the outside looking in, it may appear as though the child is behaving irrationally. It is likely though, that this behavior has a very specific and rational purpose. In other words, there is a function to this behavior.

In the case of a child with autism having a tantrum in a supermarket, the function is likely access to a toy or candy that the child desires to obtain. In the case of a child screaming in a restaurant, the function could be to escape to a more desirable location or activity. For a child in a special education class constantly interrupting the teacher while they are trying to deliver the lesson, it could be the individual attention that these outbursts achieve from the teacher or other students in the class. It could also be the case that this behavior provides its own reward, such as with hand flapping or repetitive loud vocalizations. Understanding the function of a behavior is crucial if a parent or teacher wishes to find a permanent solution.

With that in mind, here are the four main functions of behavior explained:

Access to Tangible Items

Achieving access to a desired toy or food is a common function of problem behaviors in children with or without autism. In the case of the child having a tantrum in the middle of a supermarket, it may be instructive to watch how the situation resolves itself. Often, it will end with the parent giving in and buying the toy or candy that provoked the tantrum in the first place. The next time the family is in the supermarket, can you guess what will happen if the child is denied a toy? The child is simply using the easiest and most effective method to obtain the object of their desire. To put it into perspective, access to tangible items is the reason most of us get out of bed and drive to work in the morning. The tangible item may be different (paying the rent, buying groceries, paying for children's tuition) but the function is the same.

There are a couple of critically important steps if a parent or teacher wishes to eliminate problem behaviors such as physical aggression, that occur with the goal of achieving tangible items. First, the behavior needs to stop resulting in the delivery of the tangible item. If this item is a toy, that toy cannot be delivered during or immediately after the problem behavior. Second, a replacement behavior needs to be taught. Generally, this will be some form of communication. If fully vocal, teach the child to ask nicely for the object. If the child is lower functioning, sign language or a picture exchange system may be more appropriate. Third, offer an alternative route to the object of desire, if possible. For instance, have the child earn a pre-determined amount of tokens before they can have the tangible item. These tokens could be earned by doing chores, completing class assignments, or simply not engaging in tantrums for a period of time.


Escape is another common function of behavior. In a typically functioning adult's life, this could take the form of doing the dishes to avoid making an unpleasant phone call. For a child with a developmental disability, it could take the form of physical aggression or running away. Simply getting to avoid the undesirable activity provides the reward for this behavior. Unfortunately for a parent or a teacher, the child's desire to avoid the activity may be in direct conflict with the parent's desire to have a pleasant meal at a restaurant or a teacher's desire to have their student work quietly on their assignment.

The most effective way to reduce escape-maintained problem behavior is to prevent the behavior from allowing the child to escape. This could take the form of moving the child into an area of the class where they cannot disrupt the other students but requiring them to still complete the assignment that provoked the behavior. In situations where the problem behavior is severe, such as with physical aggression or self-injurious behavior, this may be more difficult or impossible. In those situations, stopping the dangerous behavior should be the first priority. This usually will mean blocking the child as gently as possible to prevent them from harming themselves or others. In all cases of escape-maintained behavior, a replacement behavior should be taught to the child as soon as possible. This could mean teaching the child to appropriately communicate their desire to avoid the activity in question. Once they can effectively do this, they should be allowed to escape the behavior initially. Over time, though, there should be a plan put in place to reduce the amount of time that an appropriate request to avoid an activity will allow the child to escape. Reinforcement (or reward) should also be provided for successful completion of the activity.


Attention is one of the more interesting functions of behavior. That is because it doesn't always matter whether the attention achieved is positive or negative. Yelling at a child may be just as desirable to them as praise. When a teacher yells at a disruptive student to be quiet and get to work, they may be providing the child the very thing that they want most. While the teacher thinks they are punishing the child, they could actually be making the problem behavior more likely to occur again in the future. Think about people on the internet making offensive comments on message boards or social networking sites. Do they stop when another commenter tells them they are being offensive and to knock it off? Often, it will just elicit more comments from the person. The form of the attention doesn't matter as much as the fact that it is attention.

As with the behavior functions of access to tangible items and escape, the most important thing to remember about reducing attention-seeking behavior is making sure it stops resulting in any form of attention. This could involve isolating a disruptive student in another part of the class or encouraging the other students not to provide attention to the student's outbursts. In addition, provide positive outlets for this student to achieve the attention they desire. This could involve rewarding them with time at the end of class to make funny sounds or jokes to the class, provided they behave appropriately for the lessons taught during class.


Sometimes behavior provides its own reward. When a person with developmental disabilities makes repetitive movements with their hands or repeats sounds over and over, there may be no function beyond the pleasure that the behavior itself provides. These are said to be automatically reinforcing behaviors. These behaviors can sometimes be severe, like when a child repeatedly bites their hand to the point where it is breaking the skin. They can also be fairly minor, such as a person twirling their hair or repetitively tapping their shoe.

Behaviors with an automatic function can be some of the more difficult behaviors to intervene on. That is because it is very difficult to eliminate the reward for a behavior, when the reward occurs at the same time that the behavior does. There are, however, some methods that can be successful. One, a replacement behavior can sometimes be taught. For instance, if a child bites down on their hand during class, a nontoxic toy could be provided to them to bite down on that would allow them the same sensation, but without causing their hand to be damaged. Two, the behavior can be blocked from occurring. If a child hits a wall repeatedly with their hand, they can be simply moved away from the wall so they cannot reach it. Third, the behavior can be made less rewarding. In the case of the child that bites down on their hand, a bad tasting spray could be applied to their hand that would make biting down on it less pleasurable. It is important to remember, though, that with severe behaviors like these, a behavioral specialist should be consulted before beginning any intervention.

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Blain Hockridge

Blain Hockridge

Blain Hockridge is a master’s student in Applied Behavior Analysis (ABA) at Fresno State University in California. He has worked for three years as a case supervisor at an autism center serving children ages 2-6. He previously worked for two years as an instructional aid in a special education classroom. He hopes to receive his Board Certified Behavior Analyst (BCBA) certification at the conclusion of this upcoming school year.
Blain Hockridge