Basic Nerve Strength and Thresholds:

[Mick Trainer]

Basic Nerve Strength and Thresholds:

Nerve is a term often used in circles where canine behavior is discussed. It is a term many do not truly understand, nor do they understand its ideological relevance to canine behavior or its relevance as a requirement for the breeding of dogs with sound temperaments. Its most basic definition refers to a dog’s ability to handle stress, taking into account at what level of stimulation a dog shows signs of stress and how quickly the dog recovers from a feeling of stress. However, to really get a better understanding of nerve, we must look much deeper into what we mean by the term and where it really came from.

Before I discuss nerve it will pay for us to define a few terms so that there is no confusion as to their meaning.

Threshold: The point where a dog is said to first show signs of a behavior or where a dog goes from one behavior to another.

Avoidance: Where the dog wishes to avoid unpleasant stimulus. The most common example of this is running away from the object. (It may not always be as clear as this.) In the end the dog is putting distance between him and the threat or focussing his/her attention away from the threat in the hope that the threat will move away from it. Cowering and shying away from someone are classic examples of avoidance. Avoidance behavior is very closely related to defensive aggression and really exists as a part of the dog’s defensive repertoire.

Defensive Aggression: When the dog is defending life, territory, food, pack, etc. The dog will show aggression towards an object with the sole purpose of driving the object away. The trigger stimulus for a dog showing defensive aggression is “threat”, or in real terms, the “perception of threat”. Defensive behaviors can include true aggression, staring, a widening of the stance, pilo-erection (hair up on the back/neck area), etc. In its true form defensive aggression is a fear-based behavior. Many will see this type of aggression as confidence, but in real terms the dog is feeling threatened and needs to defend itself, which really shows were the dog’s weakness exists. A dog’s reaction to, and ability to deal with, a threat depends largely on the defensive strength of each individual dog. Defensive strength varies in dogs, depending on breed, maturity, gender, etc.

By defensive strength we mean - at what stimulus level does the dog first show aggressive behaviors and at what stimulus level does he go into avoidance? Defensive strength is measured in between these two points. All dogs have the ability to defend themselves through aggression when needed but how strongly they will do this varies. Dogs that have been used as protection or service dogs generally have much stronger defensive capabilities and thus will show defensive aggression through a greater range of stimulus levels.

When trainers talk about a dog’s nerve strength they are talking about the dog’s ability to deal with and to recover from stress, particularly stress caused by threat. In scientific terms this refers to the pathway between the cerebral cortex and the brain stem. Stressful information and aggression is believed to be processed and developed in the cerebral cortex. So by “nerve” we are referring to the ability of the cerebral cortex to deal with this stress and to communicate with the brain stem.

Basically, nerve strength is often referred to or divided into three main categories: weak, mid strength and strong. Many use terms like thick or thin in place of weak or strong but they usually are referring to the same thing.

A dog that is said to be of low or weak nerve strength is a dog that has a basically nervous disposition. This dog will spook very easily and may take a long time to recover. This dog will show defensive aggression at a very low level of stimulation and may also go in to avoidance behavior not long after (depending on the defensive strength of each individual dog). Common examples are dogs that show aggression towards people when these people have shown little or no real threat to either dog or handler. Dogs that bark aggressively at the gate or bark at even the slightest noise without being trained to do so are doing this because they are fearful of what that noise may be. These dogs have a high perception of threat at even the lowest stimulus level.

To the uneducated when mixed with more defensive strength dogs such as Rottweilers, German Shepard Dogs etc these dogs may seem to be good guard dogs. Most people that own this sort of dog believe that, since their dog is showing aggression, their dog will defend them. The truth is that with any real pressure these dogs will go into avoidance behavior and back off. These dogs often bite the wrong person and are often labeled as fear biters and are responsible for a large percentage of the dog bites upon children.

Weak Nerve or low threshold dogs can often be helped by professional trainers. The dog’s confidence must be raised so it is not spooked into defensive aggression at such a low level. This is done through exercises where the dog’s overall confidence is increased and where the dog is shown an alternate behavior to aggression. On occasion drug therapy is required and can be very beneficial for such dogs.

These types of dogs are also far more prone to anxiety related behavioral problems due to their lack of ability to handle stress. These dogs will often suffer from separation anxiety with the removal from a person or other dog which they see as a guardian, protector or even a safety blanket. These type situations create much fear for these dogs as they will now have to deal with the stresses life throws at them without the backup there to help them. Due to the resulting high stress levels, these type dogs are slower to learn new things and often make mistakes later in the learning process.

Mid Strength nerve: Dogs that make up the majority of dogs in the community. These dogs can be spooked and frightened but it is at a level that is not seen almost every day as can be seen with the weak nerved dog. These dogs will show signs of stress but will recover much quicker. They may bark and alarm the pack (owner) to strange goings on but will not show full blown aggression (hair up, teeth bared, etc) until truly threatened. These dogs will happily greet new people and objects without fear. Without the direct threat, no aggression will be shown.

These dogs make up the group of dogs that will suit the average family household, that want a friendly happy dog that is safe with strangers and their children but can make a fine watch dog.

Strong Nerve: A dog is said to be of high nerve strength or a high threshold dog when the level of stimulus needed for the dog to instigate defensive aggression is at such a high level that it is rarely seen. These dogs posses true self-confidence and feel that there is very little in this world that is a real threat to them. These dogs rarely, if ever, exhibit defensive aggression or avoidance.

These dogs, in the right hands, can make excellent pets. In the wrong hands, and if accompanied by a high rank drive, may produce very dominant/rank dogs that will happily challenge the owner. This is due to their high levels of confidence and the fact that they will follow through rather than back down when confronted. These dogs can often be used in the highest levels of training, including police service, etc. With their true confidence they are unlikely to back down.

Clearly not all dogs fit so neatly into such set groups and many will be in the higher or lower bracket within such groups or on the border between these groups.

Nerve strength also greatly affects a dog’s ability to learn and process information. A dog with weak nerves faced with a new situation or scenario or where he/she is being asked to perform a task by the owner that it has not done before will show signs of stress. This stress in turn causes the learning process to slow drastically. The higher the level of stress the dog feels the slower he/she will learn. A dog with good nerve strength will be able to deal with this stress better than one that has poor nerve strength and thus gain a better result in less time.

The nerve of a dog is a genetically imprinted at birth. It is directly passed on through the genes. However many things can alter the threshold level and thus create the appearance of a change in nerve strength. Threshold can be greatly affected by many outside influences. The most important of which being upbringing and in particular early socialization. A dog that has had a hard or abused upbringing or a lack of socialisation will generally show a lower nerve threshold than it was actually born with. The opposite is also true.

However, with nerve being set down at birth, the biggest influence on the true nerve development of a dog is the sire and dam. This in turn relates back to the breeder. Nerve development is passed on directly, so selecting a sire and dam that posses sound nerve development is a must if we are to breed dogs who in turn are sound in nerve. Many believe that this is easy but in real terms it is harder than it appears. To truly assess and determine if a dog possess sound nerve development the dog must be placed under stress and its ability to deal with this stress must be measured. A dog with poorly developed nerve strength will show this in day-to-day life; however, often a dog can be conditioned to show good reactions to stimuli that it sees regularly but still have basically poor nerve development. The dog must be taken out of its environment and placed in a situation that gradually lifts the stress levels. It is under this stress that the true character of the dog will be seen. Further to this it is not acceptable to breed from dogs that only make the grade. Dogs truly must be sound and must excel at such tests. The genetic pass-on factor of high nerve development is far lower than that of low nerve development. So if you breed one dog with sound nerves and one dog that is low nerve development in all likelihood the breeding will show low nerve development. Testing before one breeds is a must for any breeder serious about breeding sound dogs.

One of the best temperament tests is to work the dog at the task it was originally bred to do. What created the temperament (and temperament soundness) that most owners and breeders fell for with their breed was the job the dog was originally bred to do. Repeating this work and removing from breeding programs dogs that are incapable of doing this work will usually go a long way to selecting dogs of sound nerve development. To access a dog correctly the person doing the accessing must be adept at reading the reaction the dog gives and able to read the dog’s threshold to the stress and its ability to calm when the stress is removed.

Further to this breeders must also consider that all the pups in the litter will not be of the same nerve strength. Within every litter there are differences in almost all aspects of the pups and nerve development is no different. It is very rare for dogs to throw higher nerve development in their offspring than they posses themselves and all litters will contain some pups weaker than their sire and dam. Many breeders will breed from dogs with only mid strength nerve development believing that as the dog is sound enough for them that the mating will produce sound dogs. However while this will in all likelihood work for the strongest pups in the litter it leaves the weaker pups in the litter in high likelihood of being in the mid to low nerve threshold bracket and this is the pup most pet buyers end up purchasing.

The environment that the dog is in at the time that we are looking at the dog can greatly influence the result. Many dogs’ threshold will reduce at night or on slippery floors, etc. One of the most common things to reduce a dog’s defensive aggression threshold level is to restrict its movement and thus take away it ability to avoid the situation. To do this leaves the dog with only one option when it feels threatened and will make it feel that it must defend itself at a lower level of stimulation. Most of us will have heard the saying “fight or flight”. If the dog is held tight then the option to flee is removed from it, fight has become the only means of defense open to the dog.

Age is another aspect that can greatly affect nerve strength. It is widely believed that a dog will not be of full nerve strength until 12 months and as late as 3 years of age depending on the individual maturity development of the dog.

Throughout this piece I have spoken about how the threshold to defensive aggression is directly related to the nerve threshold of the dog. While in the vast majority of cases this is true, it would be remiss of me to say that this is the case 100% of the time. In protection/service oriented working dog terms a dog with a low threshold to aggression is said to be “sharp”. However this “sharpness” need not be related to a weakness of nerve development but actually can be due to a very pronounced defensive strength within this dog or even an aggression not based in fear. There are some dogs that will show high level aggressive responses without any of the other signals that would indicate a perception of threat. Many will define these dogs as having “fight drive”, “active aggression” or “non-classical aggression” etc. These dogs may show pronounced aggressive responses to low level stimulus but do not do so due to low nerve development. These dogs are rare, even in working dogs circles, but they do exist.

What's happening with dogs in the current era? Unfortunately in recent times the nerve strength of almost all breeds has been reduced considerably. This is due to many factors, such as poor breeding by money hungry breeders, a reduction in the number of working dogs, and breeders breeding for titles without considering the temperament of the dogs. I could go on and on and on. All breeds at one time or another have been actively bred for their working ability. Now, however, it is becoming ever more difficult to find dogs that can do the original work they were bred for. Some would say "So what. I don't want that any way". The reason these dogs cannot do this type of work is due to their self-confidence being bred out. As their confidence goes the incidence of fear biting will continue to increase. It is this soundness that is being lost as the working ability diminishes. So it does not matter whether you want a police service dog or a couch potato, if you want a sound, calm temperament then confidence/mid to high nerve development, is a must.


I discussed above how important it is for breeders to understand and breed dogs of truly high nerve threshold levels. The idea that testing and breeding for mid to high nerve development is only necessary for the breeding of working dogs is a theory I cannot agree with. Nerve development directly affects many aspects of a dog’s overall temperament including its learning ability, its ability to deal with stress, and its aggression levels. Nerve is directly responsible for how sound a dog’s temperament is and how easy and pleasurable a dog is to live with. As we live with temperament 365 days a year nothing is more imperative to breed correctly. Working dogs require many other characteristics that often a pet owner may not require but sound nerve development is a necessary part of any dog’s temperament no matter what task it is to be used for, worker or pet. Breeders who believe that they do not have to test for such things do not correctly understand the influence that nerve development has, it’s difficulty to recognize in day to day life of the dog, nor how important it is to breeding correctly temperamented dogs.

In conclusion we can see that the nerve strength of a dog can influence many aspects of a dog’s overall temperament and we must be able to see how a dog reacts to stress and how it deals with it. This is a very basic look at nerve and how it affects behavior. Many people will find themselves wanting to learn more regards this topic and there are many good sources of information available on th

[damp]

Thank you Mick... very informative post as always.

[Luvs]

Great post Mick! I always enjoy reading your posts. They are always so informative!

[Karyn]

Ya know Mick - I love your posts! I learn so much. Each time I wear your "Eastern Dog Training" sweatshirt and hat (I won the bit for it at Rott Stock) - I feel so proud. Thanks for your many contributions.

[Brooke&Ryan]

Wonderful post, Mick. Very informative. As with all of the others I always enjoy reading your posts. :)

:)
Brooke