What is Stimulus Control?

Well established cues are under what is called stimulus control. The stimulus (cue) increases the chance that the behavior will occur because the animal has been reinforced for performing the behavior in the presence of the cue. But what does it really mean for a behavior to be under good stimulus control?

Properties of cues that have good stimulus control.

1)The animal understands the cue and responds to the cue promptly every time it is given.

2)You don’t get the behavior in the absence of the cue.

3) You don’t see the behavior in response to some other cue.

4) You don’t get some other behavior in response to the cue.

I talked at length recently about teaching using Positive and Negative Reinforcement. Reinforcement is used to get and maintain behaviors. After we are getting a particular behavior, whether it’s getting a dog to touch a target, a horse to smell his tail, or a goldfish to ring a handbell, we want to establish a cue for that behavior so that we can reliably control when the behavior occurs.

The four rules above come from Alexandra Kurland’s Stimulus Control DVD. (Buy a copy of this DVD from Clickertraining.com.) These rules are a great test for determining whether a behavior is under stimulus control. Without well-established cues, we have no way of communicating to the animal what we want him to do. Much of the value in training is being able to get the behaviors we want when we ask for them.

Behavior in the absence of cues.

Simulus control seems simple, but good stimulus control makes all the difference between so-so trainers and great trainers. I think many trainers focus on the first rule and don’t worry so much about the second. We want our animals to respond reliably everytime a the cue is given. However, we often don’t want the behavior when we haven’t ask for it. 

A good example is how some owners train their horse to stand on a pedestal. The horse comes to associate the pedestal with treats and scratches and will head for the pedestal anytime she is near it. It’s a cute behavior, but if the owner does not address putting a cue for the behavior under good stimulus control, the behavior can become pretty annoying, especially if the horse chooses to perform the behavior when she’s suppose to be doing something else. 

Of course, we do want creative and innovative animals who feel comfortable offering behaviors. But, at the same time, we want to be able to control when and how an animal will respond in certain situations. For each behavior you teach, it’s good to evaluate how solid the stimulus control should be for the behavior. Are you okay with the animal offering the behavior at other times? Or do you need the animal to perform the behavior only in association with the cue? For some behaviors, you might not care if (or might even want) the animal offering the behavior even without the cue. In those cases, having the behavior under rigid stimulus control might not be as important. 

Cues must be clear and consistent. 

Any cue we use must be both clear and consistent. If we are not clear and consistent with our cues, we run into problems with rules three and four. The animal does not completely understand the meaning of the cue, so he offers a different behavior than the one that was cued. 

For example, a rider uses a leg cue when asking a trotting horse to trot faster and when asking for the canter. These are also similar to the cues that ask the horse to bend his body or move laterally. Often the rider gets angry or frustrated if the horse trots faster rather than cantering, or vice versa. Often this is the rider’s fault, if she has been less than clear about teaching the horse different cues for these two behaviors. The animal offers the wrong behavior because there is not a strong enough history of reinforcement between the particular behavior and a distinct cue.

Self-reinforcing behaviors and stimulus control. 

Certain behaviors, especially behaviors that the animal finds reinforcing, can be very difficult to put under good stimulus control. If the animal really enjoys the behavior, it can be hard for the trainer to get the animal to do the behavior only in the presence of the cue. 

For example, many dogs enjoy barking and it can be pretty easy to teach a dog to bark on cue. Our dog Ginger easily learned this skill in about 10 minutes. She got pretty excited when she figured out that she was getting reinforced for barking! Although she enjoys barking, she did not bark much before we put the behavior on cue and she still doesn’t bark very often. For some dogs, however, once you start reinforcing them for barking, it can be extremely hard to get the dog to stop offering the behavior when you ask for a different behavior or when you’re trying to teach something new.

Think of several behaviors that you’ve trained an animal. Are they under good stimulus control? How could they be under better stimulus control?

This post is part of a series of several posts on cues.