Schedules of Reinforcement

Schedules of Reinforcement

A schedule of reinforcement tells us how often we should reinforce a particular behavior. In ABA, there are two basic kinds of schedules: continuous and intermittent.  A continuous or 1:1 (one-to-one) schedule of reinforcement means that each time the child engages in a desired response, he or she will receive reinforcement. An intermittent schedule of reinforcement means that the child will receive reinforcement after some responses, but never after only one response. Examples of intermittent reinforcement are 1:10 (after every 10 responses, the child will receive reinforcement), 1:2 (after every 2 responses, the child will receive reinforcement) and 1:6 (the child receives reinforcement every 6 responses). Random reinforcement is also an example of intermittent reinforcement. In other words, intermittent reinforcement is reinforcement that occurs “every now and then.” 

When teaching new behaviors, applied behavior analysts use continuous reinforcement. This helps the child learn quickly what the correct response is because they receive reinforcement every time they do it. Also, receiving a ton of reinforcement keeps the child motivated. However, there are some issues that arise with continuous reinforcement. Number one, it would extremely difficult, if not downright impossible, for a caregiver or therapist to reinforce every single target behavior each time it happened, and to do this indefinitely. And two, continuous reinforcement eventually leads to what we call, “weak” behavior. That means that if a child is used to being rewarded for a particular behavior each time they do it, when the reinforcement suddenly stops, so does the behavior. Let’s say a child was continuously reinforced for raising her hand in class. Most likely the child will begin to expect that if she raises her hand, she will be reinforced for it each time. Remember, continuous reinforcement is great in the beginning, when teaching a new skill. But, if for some reason the teacher stopped reinforcing the child, the child would quickly give up raising her hand (and might revert to talking out of turn again!)

Given that continuous reinforcement is not practical, there needs to be a plan in place to teach the child to engage in appropriate behavior even in the absence of reinforcement. 

So how do you move from continuous reinforcement to intermittent reinforcement? The answer is, gradually. If the child is doing well with 1:1 reinforcement, move to 2:1. Then maybe reinforce after every 3-5 correct responses, and so on. This is called, “thinning” the reinforcement schedule. The idea is to end up reinforcing only at the level needed to maintain the behavior.

Behavior will remain strong overtime if it is reinforced on an intermittent schedule. Think of a slot machine at Vegas. When you play a slot machine you are reinforced intermittently, meaning, every now and then you win something. And that’s enough to keep you playing.  A person will keep pulling the slot because at some point, they have won in the past. It is the knowledge that, at some point they will win again that makes them continue to play! Of course this only applies to you if winning is reinforcing to you. But you get the point: intermittent reinforcement creates persistent, long lasting behavior.

On the other hand, let’s say you put money into a vending machine every day at lunch, and then proceed to enjoy your snack. This is an example of continuous reinforcement. What will happen if one day you put your money in and nothing happens? You might pound a few buttons, and possibly kick the machine. But you will give up rather quickly. Your past experience tells you that this machine should pay out each and every time; therefore the machine is now broken and no matter what you do, you will not get your snack. 

As you can see, intermittent reinforcement produces persistent behavior; continuous reinforcement does not. If a person is used to intermittent reinforcement, even in the absence of reinforcement, for a period of time they will continue responding. But when a person is used to continuous reinforcement, they will only continue to respond as long as they are being reinforced very frequently. 

A good applied behavior analyst is concerned about whether or not the skills taught to their client will continue in the natural environment, even after the ABA program is terminated. Gradually thinning the reinforcement schedule is one way to ensure lasting behavior change. Not only should the frequency of reinforcement be decreased over time, but the magnitude should be decreased as well. Also keep in mind that it is tangible reinforcement that needs to be decreased. Social praise, on the other hand, is a very natural form of reinforcement, and in most circumstances, caregivers are encouraged to continue praising their child for correct behavior.