If you've taken a psychology course in the past ten years, you've probably seen this short clip from The Office where Jim conducts a little experiment on his desk mate and nemesis, Dwight:
It's an entertaining illustration of classical conditioning, or learning by association, complete with a quick summary of Pavlov's famous experiment.
As Dwight, Jim, and Pavlov demonstrated, classical conditioning works by creating an association between unrelated stimuli so that over time they come to have the same effect. While Jim used a computer chime and an Altoid, Pavlov paired ringing a bell with food. When presented with food, dogs naturally salivate--they don't have to learn to do it. After repeatedly hearing a bell ring just before their food appeared, dogs learned to associate the bell with food and started to salivate.
Both examples show how important timing is to classical conditioning--the computer chime or the bell always sounded before the mint or the food appeared. We apply that same timing in many aspects of dog training. For example, when we use a marker, we say the word or click our clicker before giving dogs a treat so that over time the marker comes to predict the treat. Once you’ve repeated this pattern often enough, you’ll see your dog perk up as soon as you click or say your marker word because he knows a treat is on its way!
We can see classical conditioning everywhere. Think about what happens when you pick up your dog's leash or open a bag of treats. Does your dog get excited or come running? That's classical conditioning at work.