I have made a movie about thresholds in dog training. It gives a quick overview of the work that I presented in my webinar for the Pet Professional Guild. (Click here for a complete script of the video; or expand the audio (only) transcript below the video.)
If you are a visual learner, the movie will probably be helpful. I spend a lot of time explaining the diagrams, and have an animation of what happens to the thresholds as we train. The movie also has video examples of dogs and stimuli over the thresholds. (Plus it has a threshold of hearing test! How cool is that?**)
Threshold Movie Script
[Dogs barking]
>>EILEEN ANDERSON:
Have you ever heard a dog trainer use the term “over threshold” and wondered what it meant?
A threshold is the point or level at which something begins or changes. That’s the standard dictionary definition. But the interesting thing is that there are actually three physiological and psychological thresholds that are important when we are training our animals.
The first threshold we need to know about is the sensory threshold as defined in psychology. Here’s a definition: “The faintest detectable stimulus, of any given type, is the absolute threshold for that type of stimulus.” Have you ever heard the term, “threshold of hearing?” Right now during this slide I am playing a high frequency hum. Can you hear it? If not, it is under your threshold of hearing for that frequency. If you can hear it, it is over the threshold.
The sensory threshold is involved when our dogs are able to see, hear, or smell something new in their environment.
Another threshold is the threshold of reactivity or fear. This is the one people usually mean when they say their dog is over threshold. The most general definition of this threshold is the point at which the sympathetic nervous system responds when the animal is afraid. This causes chemical changes in the body and overt behaviors usually falling into the categories of fight, flight, or freeze.
Dogs who are aggressing are generally over the threshold of fear. Here are two other examples of dogs over that threshold.
[vet clinic noises]
>>EILEEN:
She’s panting, but it’s not hot.
She’s hyper vigilant.
Trying to escape, or hide.
And trembling.
This dog is practically paralyzed with fear.
But there’s one more threshold, and it’s located behaviorally between the other two. If one threshold is where the dog sees something, and another is where the dog freaks out about it, what’s in between?
The point at which the thing becomes aversive, where the dog starts to be uncomfortable with it. This could be called the threshold of stimulus aversiveness.
Here is an example of a dog in a situation where a stimulus is over the threshold of aversiveness. In other words, she is stressed about something in her environment, but so far she is holding it together.
[Neighborhood noises: siren in distance, children talking, birds, a sudden thump]
>>EILEEN:
She repeatedly licks her lips and looks behind her.
She’s responding to my cues, but she’s worried about the noises.
In my webinar on thresholds in dog training, I made diagrams of these thresholds, and discussed where each of our common training protocols falls among the thresholds. Here is a summary of those diagrams.
The black line represents distance from or intensity of the stimulus.
All three of the protocols discussed here take place over the threshold of stimulus perception, since the animal has to perceive the stimulus to learn about it.
The combination of desensitization and counterconditioning is correctly practiced under the threshold of stimulus aversiveness.
Protocols that use negative reinforcement straddle the threshold of stimulus aversiveness. The animal is exposed to the stimulus at an aversive level, and escape from the aversive level of the stimulus is used as a negative reinforcer for appropriate behaviors.
The closest proximity to the aversive stimulus may be more or less than I show here; the important point is that negative reinforcement protocols have to cross the threshold of stimulus aversiveness to work.
Flooding takes place at or above the threshold of fear.
The thresholds aren’t always spaced out nicely. For example, if the threshold of perception and the threshold of aversiveness are very close together in space, a trainer using desensitization/counter conditioning would probably not use distance as the initial way to keep the stimulus non-aversive. The trainer would probably use a different form of the stimulus first. This configuration of the thresholds is probably common with wild animals.
Likewise, if the threshold of stimulus aversiveness and the threshold of fear are very close together, a negative reinforcement protocol would be very difficult to perform without risking flooding.
Finally, the thresholds move because of environmental factors, the animal’s stamina and psychological state, and of course as we train. This is what we hope will happen as we train.
For more information on thresholds, please see the links to my webinar and blog in the video description. Thanks for watching!
** For the auditory people, musicians, and nerds among us (I’m all three): I used an iPhone app to generate a high frequency sinusoid (15.5 kHz) and recorded it for the movie. I used an oscilloscope app to make sure that the sound was playing during that part of the movie, through my own computer anyway. It’s just below my threshold of hearing. Younger people can probably hear it, if their computer speakers can generate it.
