Dipper training CyberRat: What's going on

What's really going on when you conduct the procedure that Malott calls "dipper training" and that is often called "magazine training?"

As you'll learn in Ch. 20, a stimulus can have more than one function. In the case of the sound that Malott calls the "dipper click," this stimulus takes on more than one function as a result of dipper training. We start the process by pairing the sound with a stimulus that's already an effective reinforcer for a thirsty rat – a drop of water. As we learn in Ch. 11, this pairing of a neutral stimulus with a reinforcer causes the neutral stimulus to become a reinforcer too – a learned reinforcer. It's important for this sound to become a learned reinforcer so that we can then use it to provide immediate reinforcement for other behaviors in the Skinner box. Imagine that you wanted to train the rat to stand on its hind legs in the left front corner of the Skinner box. If a drop of water were the only reinforcer available, then could you present it immediately following that behavior? No way.

But if the sound of the dipper click has become a reinforcer, then you can present that sound immediately following whatever behavior you choose. That's why dipper training is so important, and why it has to happen before any other training can take place in the Skinner box.

Now, as we learn in Ch. 12, a discriminative stimulus (S^D) is a stimulus that functions as if it's a signal that if the target behavior is performed, it will be reinforced. When we conduct dipper training properly, in addition to the dipper click becoming a learned reinforcer, it also becomes an S^D for the behavior of going to the dipper. When the dipper click sounds, if the rat goes to the dipper that behavior is reinforced by the drop of water that's there. But remember that in order for a stimulus to be an S^D, there also has to be an S^Δ. In this case, the S^Δ is the lack of a dipper click. If the rat goes to the dipper in the S^Δ condition, that behavior is not reinforced.

In the dipper training exercise with CyberRat, the indicator that we've been successful is that the rat will go to the dipper from anywhere in the Skinner box upon hearing the click. In other words, the sound functions as an S^D. When we see this, we can also be confident that the dipper click has become a learned reinforcer, which is what we are trying to accomplish in this lab.

Remember, though, that when we do the exercise properly, the dipper click is not being used to reinforce any behavior. In a reinforcement contingency, the reinforcer is presented after the target behavior, and during dipper training the dipper click is presented before the behavior we want to see, which is going to the dipper. This is why the instructions warn you not to present the dipper click consistently when the rat is in a particular place or doing a particular thing, because that would result in reinforcing that behavior or being in that spot. Instead it's important to allow the rat to go different places in the box and to do different things before presenting the dipper click.

When we get to Ch. 20 on behavioral chains, we'll revisit this idea of a particular stimulus functioning as both a reinforcer and an S^D.