The term 'threshold' can have a variety of uses, but when you simplify it (and I am ALL for simplifying), it just a clear point at which something changes. The line between desirable and undesirable behavior :). So from a dog training perspective the threshold is an 'imaginary line' where a stimulus is intense enough to produce an effect on your dog - the exact point where your behavior starts to break down.
|Bourbon over threshold at a Coursing event.|
The threshold of your life
All dogs have a threshold. Some dogs, like Bourbon, have low thresholds - his behavior becomes undesirable VERY quickly in the presence of stress. Other dogs have high thresholds, sometimes I wish I had one of those dogs :). Generally, when a dog is under threshold, they appear calm and under control, and they are capable of taking treats (this can be an important facet of thresholds). When a dog goes over threshold, there are varying responses depending on their personality. Some shut down and withdraw into themselves, and may avoid the stressful object or situation (this type of reaction is sometimes hard for dog owners to realize). Other dogs appear out of control (think Bourbon!) - screaming, lunging, and generally making a huge display of anxiety and arousal. These are much easier recognized and what everyone refers to as reactive.
So why are thresholds important? If your dog has gone over threshold then they are too stressed to learn. Their flight or fight instinct has been activated in the brain and learning cannot take place because factors of survival become the primary importance. But just to make it harder for us :), threshold levels are fluid and contextual. For example, your dog may do fine 10 feet away from a trigger today, but tomorrow he may be reactive at 15 feet away. The threshold levels vary depending on several factors - location, number or types of people or dogs present, physical considerations, hormones, past history or assocations - the factors are endless.
Seeing is job #1
So how do you gauge your dog's threshold? Mostly through observation of four major things: overall body language of your dog, their automatic reflexes, the environment, and your dog's response to the environment. Dog owners, especially those with reactive dogs, need to learn how to assess their dogs and the environment continually. So learn as much about dog body language as you can, especially your dog's body movements during a wide variety of emotions. And when watching the environment pay attention to triggers and patterns. Notice which things cause your dog to go over threshold - you want to be able to predict what will cause your dog to react (but try not to anticipate a reaction!) so that you can adjust your distance or intensity accordingly. As your training goes on you'll find that your dog's threshold is changing. They should be able to keep it together better, and longer, in the presence of triggers.
It's a balancing act to find what is 'just right' to have our dogs be successful in any given situation. For those of you lucky enough to have a 'normal' dog, it's still important to learn your dog's body language and understand how they respond to the factors in the environment. Remember, all dogs have a threshold so pay attention to the early warning signs of stress