Dogs learn from the immediate consequences of their actions. This gives a trainer several ways to influence a dog’s behavior, we feel ethically bound to use 100% reward based methods:
REWARD (increases probability of behavior R+)
“TIME OUT” (decreases probability of behavior P-)
Older-school dog training relied heavily on the “scary stuff,” such as jerking the dog’s neck using a metal collar (P+ & R-), to motivate the dog. Dog-friendly methods have since developed that make greater and more sophisticated use of giving rewards and removing rewards as principle motivation. The control is as good as that achieved with traditional "old school" methods and avoids the side-effects (fear and aggression) of the use of pain and "scary stuff".
Fear and Aggression
Systematic desensitization is a technique that was originally developed by behavioral psychologists to treat people with anxiety and phobias. The subject is exposed to a fear-evoking object or situation at an intensity that does not produce a response.
Desensitization is most often performed in conjunction with another technique, counterconditioning, which is an application of classical (or Pavlovian) conditioning. In classical conditioning, when one event becomes a reliable predictor of another event, the subject develops an anticipatory response to the first event.
Dogs learn that a leash coming out of the cupboard means a walk is next. Pairing one stimulus with a meaningful second stimulus can create a Conditioned Emotional Response, or CER. We can actually teach dogs to like things.
Classical Counterconditioning is about changing associations. It’s called counterconditioning rather than simply conditioning because the dog already has an unpleasant emotional response to the thing we’re trying to condition, so we counter that by establishing a pleasant CER. So, a dog who is uneasy around strangers learns that their presence, proximity and later, contact, predict his favorite things in the world.
How this looks in actual treatment is the presentation of a low-enough intensity, or subthreshold, version of the trigger, immediately followed by a potent, pleasant counter-conditioning stimulus. This is repeated until the dog is evidently and eagerly anticipating the counter-stimulus when the trigger is presented. Then, the intensity of the trigger is increased and the procedure repeated.
See Classical Conditioning in action!