Stimulus Control: The Most Important Concept You've Never Heard Of

The fourth principle of behavior I want to discuss is Stimulus Control.  This is probably the least talked about in dog training with new dog owners, but also an incredibly vital piece of training your dog.  I’m going to break it down to its most basic meaning in this post and then in subsequent posts talk about how good stimulus control can be achieved. The definition of stimulus control is when a behavior changes in a particular way depending on whether a given stimulus is present or absent.

To make sense of that definition, let’s start with the word “stimulus.”  A stimulus is anything that affects the senses.  Examples include the sight of a red traffic light, the sound of a loud honk, or the feeling of rough pavement underfoot. Stimuli are exceedingly important when talking about dog training because they are the reasons dogs behave a certain way.

People, like any other animal, perform certain behaviors in the presence of certain stimuli.  If you were driving down the road and suddenly saw a red light, a stop sign, a rolling ball, or a pedestrian – or if you heard a loud honk, or your passenger yelled “stop!” – you would probably apply the brakes quickly! All of these stimuli change your behavior.  You have learned, through rules or experience, that stopping is a really, really good idea in the presence of those stimuli.  You will be rewarded with your passenger’s approval, or you will avoid the punishment of an accident or a ticket.

In other words, stimuli like red lights and stop signs act as signals to you that some type of reinforcement or punishment is now available. This is the “control” piece.  The stimulus “controls” whether a behavior will occur if it acts as a signal that reinforcement or punishment is available for that behavior.

How does that apply to dog training?  Well, your dog sits all the time, for various reasons – fatigue, the need to scratch an itch, etc.  However, you can control your dog’s sitting behavior by teaching her that the cue word (stimulus) “sit” means reinforcement is now available for sitting.  In the beginning, reinforcement is almost ALWAYS forthcoming when you say, “sit”; it is the green light to your dog that if they plonk their butt down right now, they will get a cookie. My dogs are well advanced in their training and might get a cookie only every hundred times I say sit, but they still know that the best moment to sit is when I cue it, because that is the time when reinforcement is a possibility for that behavior.

Without the cue, the likelihood of getting a cookie for sitting is slim.  If there were no clear cue (or stimulus) to tell the dog when sitting will likely receive reinforcement, the dog would end up sitting all the time just on the off chance that something would appear.  Oftentimes, the cue becomes a person holding a treat- and that is something we don’t want!

This is where good stimulus control comes in.  If you’ve done your training “right,” with good stimulus control, you’ll get a dog that sits immediately upon being cued, but at other times during training won’t “try it out” in hopes of getting a treat without a cue.  This is how you avoid having a dog that “throws” random behaviors at you.  When you say, “down,” they won’t first sit, then touch, then spin, and then finally lie down.  With good stimulus control, the dog will perform the correct behavior – and nothing else – when cued for that behavior.

These are the four features of a behavior with good stimulus control as listed on Karen Pryor’s ClickerTraining.com.

The response is said to be 'under stimulus control' when presentation of the particular stimulus fulfills these four conditions:

      1. The behavior is always offered when that cue is presented
      2. The behavior is not offered in the absence of that cue
      3. The behavior is not offered in response to some other cue
      4. No other behavior occurs in response to that cue.

(from http://www.clickertraining.com/glossary/17#term21269)

Which of these elements of good stimulus control is the most problematic to achieve?  Well, that depends on your training method and is a subject for another post!