Pavlov Stumbles on Classical Conditioning
Many of us know who Ivan Pavlov was, and that he is best known for conditioning dogs to salivate at the ringing of a bell. What many people don't know is his original experiment with the dogs had nothing to do with behavior; rather he was testing their saliva and how its chemistry changed in the presence of food.
In his testing, he noticed the dogs began salivating at the sight of the lab assistants (who gave them food) before any food was actually present.
What he'd inadvertently done was teach the dogs that lab assistants = food. A dog's natural, reflexive response to the sight of food is salivation, therefore upon seeing the lab assistants the dogs would salivate in anticipation of the food they knew would follow.
Pavlov also used bells to call the dogs to their food, thus resulting in the conditioned response (salivation) to a previously neutral stimulus (the bell).
What is Classical Conditioning?
Classical Conditioning is the associative linking of stimuli which trigger reflexive responses to previously neutral stimuli which did not elicit the reflexive response. This differs from operant conditioning in that it deals with innate responses; not behaviors.
- Unconditioned Stimulus (US): consistently triggers a reflexive (unconditioned) response
- Unconditioned Response (UR): reflexive response triggered by an unconditioned stimulus
- Conditioned Stimulus (CS): a neutral stimulus which produces no reflexive response
- Conditioned Response (CR): the reflexive response (previously unconditioned) triggered by a conditioned stimulus
Specifically, this type of associative learning pairs CS with US in order to trigger the reflexive response (which therefore becomes conditioned) from the CS. Let's look at an example using Pavlov's dogs and the bell.
Pavlov rang a bell to call the dogs to dinner. Of course he saw that the presentation of food (US) stimulated the dogs into salivating (UR). This response is reflexive, or involuntary, and was a result of the dog's body preparing to receive food.
Then he began to notice that whenever he rang the bell (CS) the dogs would salivate (CS). Because of the constant pairing of the bell (previously a neutral stimulus) with the food (an unconditioned stimulus), the dogs learned to associate the two as equal.
Food (US) --------------------> Salivation (UR)
After repeated pairing of Bell & Food:
Bell (CS) -------------------> Salivation (UR becomes CR)
So, how can you utilize classical conditioning as a training tool for dogs since it doesn't deal with behaviors, only reflexive responses?