What is a neutral reinforcer?

During the course of our day to day lives we ask for many different things. We may ask the person at a lunch counter for a cup of coffee, we ask our children to get ready for school, we may ask the dog to sit down, and we may even ask inanimate objects to do things like telling our computer to “open” when a program is slow in responding. The reason we ask for so many different things is because we, like most people, have a variety of items and events that serve as reinforcers. Many things are valuable to us depending on our circumstances.

Many children with autism have an extremely limited range of items and events that serve as reinforcers. Because these children may not be reinforced by a wide range of experiences, there may be a general tendency for them to respond to their environment with less variability in behavior. According to all descriptions of autism this is a defining characteristic of the disorder. If there is not a wide pool of reinforcers available to a student, the number of mands that can be taught will be quite limited. In order to teach a diverse mand repertoire, effort must be given to extending the number of events that serve as reinforcers.

As indicated in basic behavioral research, the stimuli that serve as reinforcement do not remain static. Some reinforcers will remain strong, others fade in strength and some neutral events gradually take on reinforcing characteristics. These processes are not random, however. The value of items or other events that serve as reinforcers or as neutral stimuli can be altered through teaching.

A basic behavioral principle is that an event that repeatedly occurs in close time with presentation of an already established reinforcer can in itself become a reinforcer. This is the concept of conditioned reinforcement. Conditioning occurs when the two events (the established reinforcer and the neutral event) occur close in time and contingent on some other behavior. Most of the things that serve as reinforcement for us in our day to day lives have been learned through this process. For instance, we have learned to like car keys because they are associated with another reinforcer, namely taking car rides. If money wasn’t paired with access to a wide range of things that are important to us, it wouldn’t have value. We have learned to like money.

The principle of conditioned reinforcement can be a major tool in our work with children who may not have a wide range of established reinforcers. The power of this principle lies in the fact that we can teach others to like things that they otherwise may have ignored.

• Bubbles are a neutral stimulus: the student regularly ignores them when they are presented as a probe item on a preference assessment
• Bubbles are presented and then immediately after the bubbles are blown, some candy is given to the student. Candy had previously been determined to be a strong reinforcer.
• Bubbles are repeatedly paired with candy and other known reinforcers.
• Eventually the child begins looking at and even reaching toward the bubbles.
• Blowing bubbles then become an event that can serve as reinforcement for the student.

A second way of conditioning new reinforcers is more technical, but simple in its implementation. One can condition a new item as reinforcing by making its presence necessary for some other event to occur. In other words to get what you want, you have to first get something else to occur. If this happens enough you learn to like the other item almost as much as the first. For instance, a person may learn to like a certain store because the particular store sells their favorite things. Eventually the person learns to like going to that store even if they aren’t going to buy anything.

Dr. Jack Michael explains this in his book (Michael, 2004), Concepts and Principles of Behavior Analysis. He notes that an event that serves as a reinforcer through behavior evoked by a transitive motivative operation can later take on reinforcing characteristics. It is fair to say that events can serve multiple functions. He notes that many and probably most forms of conditioned reinforcers are dependent themselves upon other stimulus conditions. We begin to like the stuff that is associated with our obtaining the stuff we like.

• A student enjoys playing with certain toy figurines on the floor.
• The student’s teacher may start delivering the toys to the student by having them drop down a tube.
• In order to access the figurines, the student needs to have the tube present (the MO for figurines establishes the value of the tube and evokes all tube getting behavior.)
• Prior to this the tube was a neutral stimulus.
• Now, due to the CMO-T effects (needing the tube to get the toys), access to the tube becomes a conditioned reinforcer.

A secondary reinforcer is a stimulus that reinforces a behavior after it has been associated with a primary reinforcer. For example: When you give your dog a food treat and tell him "good boy," he's getting both the primary stimulus of the treat and the secondary reinforcer of the verbal praise.

Primary reinforcers are biological in nature. Secondary reinforcers require association with these innate reinforcers before they can produce a response. So, your dog may not associate the verbal praise with a reward unless you combine it with the food treat.

The American Psychological Association defines a secondary reinforcer as a neutral stimulus that can enhance the likelihood of a future response by being paired with a stimulus that naturally enhances that response.

By rewarding certain behaviors, we're encouraging those behaviors in the future. However, not all reinforcers are the same. Some can be more motivating than others. The dog from our earlier example is more likely to be highly motivated by a primary reinforcer like a treat than a pat on the head (the secondary reinforcer) ​because food satisfies a strong biological need.

If the dog's trainer wanted to pair that food with some type of secondary reinforcer, such as the sound of a whistle, the sound of the whistle would eventually become associated with the food and serve as a form of secondary reinforcement.

Primary reinforcers occur naturally and do not need to be learned. Examples of primary reinforcers, also sometimes referred to as unconditioned reinforcers, include things that satisfy basic survival needs, such as water, food, sleep, air, and sex.

Secondary reinforcers are also called conditioned reinforcers and do not occur naturally and need to be learned. Money is an example of a secondary reinforcer. Money helps reinforce behaviors because it can be used to acquire primary reinforcers such as food, clothing, and shelter (among other things).

Another difference between secondary reinforcers and primary reinforcers is the areas of the brain where they are processed. Primary reinforcers appear to more strongly affect older brain regions (such as the anterior insula) whereas secondary reinforcers more strongly impact newer areas of the brain (such as the anterior orbitofrontal cortex).

Secondary Reinforcer

• Neutral stimulus (reinforces only when paired with a primary reinforcer)

• Only tied to biological needs through association

• Needs to be learned

• Also known as conditioned reinforcer

• Processed in newer areas of the brain

Primary Reinforcer

• Natural stimulus (reinforces naturally, doesn't need to be paired with another reinforcer)

• Directly tied to biological needs

• Does not need to be learned

• Also known as unconditioned reinforcer

• Processed in older areas of the brain

Token economies are a good example of how a secondary reinforcer can be used in operant conditioning. Token economies involve rewarding people with tokens, chips, or stars for good behaviors. These tokens can then be exchanged for other items that the individual desires.

Parents, teachers, and therapists frequently use secondary reinforcers to encourage children and clients to engage in adaptive behaviors. While they have no inherent reinforcement value in and of themselves, such tokens can be used to purchase primary reinforcers such as soda, candy, and other privileges. Once this association has been made, the tokens themselves become reinforcing.

So, what are the benefits of using a secondary reinforcer? Why not just skip the trouble of forming an association and simply use a primary reinforcer instead?

As you can probably already imagine, primary reinforcers are only reinforcing if the subject is in a state of deprivation. A dog is unlikely to perform tricks in exchange for a treat if the animal is full and satiated, for instance. Likewise, a child is unlikely to clean their room to receive a treat if they just finished eating lunch.

A secondary reinforcer allows the trainer to continue to deliver reinforcement even if the subject does not have any biological needs at the moment.

Secondary reinforcement is less susceptible to satiation. So, it provides the opportunity to deliver reinforcement at any time.

Secondary reinforcers use operational conditioning principles to help reinforce the desired behavior, even if the subject's biological needs have already been met. Thus, they can be useful in a variety of situations, from home to school to therapeutic settings.