Thank you to Debbie Jacobs and Randi Rossman who made suggestions about this. All conclusions and any errors are my own. 

Have you heard the term “opposition reflex” used in dog training? It’s used pretty often. But recently I got to wondering whether the opposition reflex was really a reflex. (Quick answer: “No.” Shortest blog post I’ve ever written.)

Would you like to hear the story anyway?

First, some context. I gathered the following quotes about the “opposition reflex” from a selection of dog training articles.

• The dog’s opposition reflex [is the] instinctive reaction to push against a push.
• Dogs have a natural resistance to pressure called the opposition reflex.
• If dogs are pulled in one direction, they will automatically pull in the other direction.
• The opposition reflex is your dog’s natural instinct to resist pressure.

Wow. Instinctive! Natural! Automatic! But then I started looking for the term “opposition reflex” in lists of actual reflexes. I looked in biology, physiology, and learning theory textbooks. I looked in scholarly articles.

Results: nothing.

Virtually all mentions of the so-called “opposition reflex” are in lay articles about dog and horse training. So where did this term come from and why do we use it? It’s not in the textbooks.

History

We have Pavlov to thank for part of the confusion about the opposition reflex. Interesting, since he was a physiologist. Pavlov came up with the term “freedom reflex” for the escape behaviors of a dog who strongly resisted the harness he used in his laboratory. He generalized it to all organisms. (It turns out that Pavlov liked to call all sorts of things reflexes. That is a whole other discussion.)

Most scholars agree that Pavlov grossly over-generalized from the actions of the dog, and was mistaken in calling what was essentially resistance to coercion as a reflex. As one of his critics states:

There is of course no reflex of freedom, although it is easy to see resistance to coercion in animals and humans. Herding cats is nearly impossible, and it is equally hard to keep male dogs from sniffing females in heat. Wild horses resist taming, and most animals cannot be domesticated at all. Human beings fiercely resist unwanted control. But struggling against coercion is not a reflex — it is nothing like a simple atom of behaviour. –Baars, Bernard. “IP Pavlov and the freedom reflex.” Journal of Consciousness Studies 10, no. 11 (2003): 19-40.

But decades after Pavlov, trainers grabbed onto the concept of the freedom or opposition reflex. Mentions start to appear in the mid-1990s in training literature, first applied to horses, then to dogs, as far as I could tell. Some authors connected the two terms, as in this article: “Opposition Reflex in Horses.” It’s pretty clear that what many people refer to now as the opposition reflex is a direct descendent of Pavlov’s freedom reflex. The problem? It never was a reflex and it’s still not a reflex.

What Is a Reflex?

Reflexes are involuntary, discrete, and consistent behaviors. As Baars mentions in the quote above, they can be thought of as “atoms of behavior.”

A reflex is an automatic response to nerve stimulation. –Alters, Sandra. Biology: understanding life. Jones & Bartlett Learning, 2000.

Some examples of reflexes in dogs are:

• the scratch reflex (dog’s leg kicks when you scratch them on certain parts of the body);
• the palpebral reflex (dog blinks when the skin below the corner of the eye is tapped);
• the pupillary light reflex (the pupil of the dog’s eye contracts when a bright light is shined on it);
• the withdrawal reflex (dog pulls foot away when toe is pinched);
• and many more, including at least 10 other reflexes having to do with stimulation and response of parts of dogs’ legs.

These are immediate, involuntary responses.

Pavlov’s so-called freedom reflex consists of much more varied behavior, sometimes chains of behaviors, which comprise methods of escape or regaining balance. These behaviors vary to the extreme by species and individuals. A large, gentle animal might just walk away if you tried to restrain it without any special equipment. But anyone who has ever tried to handle feral kittens knows that their methods of trying to escape are typically painful and actually dangerous (because of the possibility of infection from scratches and bites) to humans.

What are typical situations in which an animal might exhibit these compensatory or escape behaviors?

1. The animal is trying to get to something and is being restrained
2. The animal is trying to get away from something and is being restrained
3. The opposite can also occur: the animal is being forced to move and is resisting, as when a trainer tries to force a sit by pushing the dog’s butt down.
4. The animal has been knocked off balance and is trying to regain equilibrium.

(I’m omitting situations where the animal has been trained to create or maintain pressure, such as a roping horse who can hold a cowboy’s line taut, or all sorts of animals that pull sleds or carts.)

Do you see the pattern here? In all cases, the animal is resisting force, confinement, or physical discomfort. When we use the phrase “opposition reflex,” we are often neatly sidestepping the fact that we are trying to get the animal to do something it doesn’t want to do. It’s a shortcut, a label that unfortunately encourages us to leave out our agency in the matter.

When Is This Discussed in Dog Training?

The so-called opposition reflex is generally brought up in discussions about leash walking, molding behaviors, and play.

Leash Walking

Countless writers highlight a dog’s supposed opposition reflex when discussing why a dog won’t yield to leash pressure, but instead, might pull the other way. Reducing the reasons a dog might not yield to leash pressure, or will take action to create it, to an “opposition reflex” is simply applying a label. It gives us no insight into the situation. Many writers grab onto the phrase without considering the many sources and reasons for this behavior:

• First and foremost, many dogs naturally travel much faster than we do. They want to get moving. This creates a taut leash as our slowness holds them back.
• They are trying to get to something interesting, and we are passively or actively slowing them down. Again, this creates a taut leash.
• We are trying to get them away from something interesting, and they want to stay there. This time, we are actively creating the taut leash.
• They are frightened and trying to get away from us, the leash, or something else they perceive as threatening.

Positive reinforcement-based trainers try to avoid these situations anyway. We don’t want to drag our dogs around. To me, it seems much more helpful to understand that the dog is wanting to go at a different speed or to a different location than to reduce it to “opposition reflex.” The “opposition” part can make them sound downright contrary, instead of being creatures with their own agency and interests. On the other hand, the “reflex” part obscures that their behavior may be a visible indication of what they want or intend. Reflex sounds like they pull because they can’t help it, not because they are motivated by something.

Training by Molding Behaviors

The second place you read about the “opposition reflex” is in discussions of molding as a training technique. This is not a method that positive reinforcement-based trainers use, but it bears mentioning because people who do use it bring up the opposition reflex. It’s found in the old “push the dog’s butt down to teach him to sit” method. If you’ve ever tried it, you’ve probably experienced what people call the opposition reflex. It is an instant resistance by the dog to being pushed. It’s very common. It’s resistance to being thrown off balance and/or coerced. But again, labeling it “opposition” can even make it sound like this resistance is naughty or defiant.

Play and Restrained Recalls

A final situation in which people discuss the opposition reflex is in activities that involve drive and enthusiasm. For instance, some agility trainers use what are called “restrained recalls.” A partner restrains the dog while the handler calls her. The dog’s struggle to escape can result in a faster recall when she is released.

Note that the latter situation matches my description #1 above: the dog is trying to get to something and is being restrained. If you have a play history with your dog, this can be fun for the dog. But it’s pretty obvious it’s not a reflex–they are trying to get to something.

Here’s an example where I am restraining my dog in a training/play situation. Check out 0:26 in the video.

Link to the video for email subscribers.

I contend that Summer’s pushing against my hands as I pull her backward is not a reflex. We’re seeing a dog who wants to run forward and get to the garden hose.

Thigmotaxis

Oxford Reference defines the term thigmotaxis as “Movement towards or away from a solid object in response to tactile stimulation.” Several readers suggested this as an explanation for the opposition reflex.

The classic example of positive thigmotaxis is rodents’ tendencies to walk staying in touch with walls and other vertical surfaces. Negative thigmotaxis is a movement to avoid certain stimuli, and is seen in fish and unicellular organisms.

The idea that the “opposition reflex” is some kind of thigmotaxis appears to come from the work of Steven R. Lindsay. In Volume 1 of his Handbook of Applied Dog Behavior and Training, he suggests that the opposition reflex is an example of thigmotaxis. But in Volume 3, he rescinds his recommendation of the term thigmotaxis for response to leash pressure and returns to using the term opposition reflex. It’s pretty clear that his original citing of thigmotaxis was an educated opinion, not based on experimental literature. And he changed his mind.

Positive thigmotaxis (turning **toward** touch or pressure) is seen in neonate puppies in the behavior of rooting for a nipple. Other than that, I haven’t seen it listed as present in dogs.

What’s the Problem With the Phrase?

I think we should question our use of the phrase “opposition reflex” because:

• It’s a label—it can stand for dozens of different behaviors.
• The behaviors it is used to describe are generally not reflexes.
• It discourages us from analyzing and asking why the behavior is being performed. (E.g., the leashed dog simply wants to go faster.)
• It discourages us from looking at our role in setting the stage for the behavior.
• It discourages us from determining the consequences that are driving the behavior.
• It sounds automatic, nonvolitional.
• It also sounds negative. Opposition sounds like defiance.
• It promotes confusion about respondent and operant behaviors.

I don’t think the term is going away anytime soon. But I hope we can get better at actually observing and describing behavior and understanding its causes and consequences. If we did that, this term would be left behind.

Have you heard the phrase in more contexts that I have listed? Have you ever seen a true reflex mentioned when discussing the opposition reflex?

Addendum

Wow, opposition in the trenches. (I’m going to avoid the obvious joke there.)

To anyone who wants to claim that the opposition reflex in dogs is a true reflex/respondent behavior/thigmotaxis, the burden of proof is on you. I have already tried and failed. You may succeed, then I’ll retract appropriate statements and amend my post. To provide evidence you will need to do the following:

1. Cite a source listing the “opposition reflex” as a true reflex from a canine anatomy/physiology, neurology, or another veterinary textbook.
2. Show that near 100% of neurologically healthy dogs demonstrate it in the same way.
3. Show the body part that can receive the stimulus and nerve group involved.
4. Show that the same physiological response is consistent.
5. Show that it can’t be punished or reinforced (though it could be attached to a new stimulus).

As I mentioned, I have already tried and failed to find these things. Please let me know if you find them.

Photo Credit: © Can Stock Photo Inc. / Vishneveckiy

Text copyright 2016 Eileen Anderson