No matter what you call them – shock collars, e-collars, or the more scientific-sounding "collar mounted electronic training aids" – are designed with the most basic form of learning in mind, operant conditioning.
How Do Shock Collars Work?
From a psychological perspective, the idea is remarkably simple. An animal has a behavior you'd like to reduce or eliminate, and you apply positive punishment in an effort to do so. The "positive" refers to the application, rather than the withdrawal, of a stimulus; the "punishment" refers to the intended effect, which is the elimination of an unwanted behavior. When a child misbehaves and a parent yells at him, that's also an example of positive punishment. Despite the fact that the Father of Operant Conditioning himself, B.F. Skinner, maintained that reinforcement was more effective than punishment in modifying behavior, some animal trainers do incorporate punishment into their trainers' toolbox.
Shock collars apply a brief electric shock to the dog's neck through two blunt electrodes that make contact with the skin. The owner can usually set both the intensity and duration of the stimulus; some models allow for increasingly longer or more intense shocks each time they're activated. For a shock collar designed to prevent a dog from incessant barking, the hope is that eventually, the lowest activation will be sufficient, provoking perhaps mild discomfort in the dog rather than intense pain.
Left: A typical shock collar. (polymath38/Wikimedia Commons)
What Are The Arguments?
There are, undoubtedly, theoretical welfare risks, at least if shock collars are used improperly. For example, for effective conditioning, the electric shock must be clearly linked with the undesired behavior. The most common way to foul up their association is by improperly timing the punishment to immediately follow the behavior. In other words, you can shock a dog all you want, but if it can't make the association between the pain and its own barking, then it will never learn to stop.
This is an extremely nuanced point: there is no question that shock collars have the capability of inducing distress in an animal. However it is not necessarily the case that they induce distress "when used in accordance with best practice by trainers experienced in their use," writes University of Lincoln researcher Jonathan J. Cooper in the journal PLoS ONE.
On the other hand, various veterinary associations claim that reward-based methods can be equally effective as punishment-based ones, and lack even the possibility for welfare risks.
Their use is illegal in at least four European countries (Austria, Denmark, Finland, Germany) and is restricted in three others (Czech Republic, Hungary, Italy).
The Companion Animal Welfare Council, a UK-based organization, pointed out in a recent working paper that there is lots of emotional rhetoric on either side of the debate, but not much scientific evidence regarding the efficacy or welfare consequences of shock collars used properly. The scant research that has been done on the use of shock collars has focused primarily on dogs being trained for police work or hunting, while the most common use is with regular household pets. That's why Cooper and colleagues set out to determine (1) whether shock collars used to train household pets were effective, and (2) what were the associated welfare consequences.
A Scientific Approach
Cooper's group rounded up 63 pet dogs in the UK, none of whom had prior experience with shock collars, and all of whom were older than six months, and whose owners reported some persistent problem that they wished to eliminate. Approximately half were male and half were female. The dogs were split into three groups, with roughly equivalent distributions in terms of sex, age, and breed.
Group A was trained with the use of electronic shock collars. The dogs in this group were trained by "two experienced dog trainers [who] were nominated by The Electronic Collar Manufacturers Association (ECMA)." Each owner worked with half the dogs in the group. The trainers used either the Sportdog SD-1825E or the Dogtra 1210 NCP. In addition, dogs were rewarded with positive reinforcement such as food, play, or praise for compliance with their instructions.
The dogs were trained to herd sheep not to harass livestock in the experiment. (C. MacMillan/Wikimedia Commons)
The same trainers worked with Group B, but without the use of shock collars. By including this group, the researchers could control for variables related to the trainers' own personalities.
Finally, a pair of trainers who belonged to the Association of Pet Dog Trainers (APDT), a UK-based group opposed to the use of shock collars, worked with Group C. The training period in all cases lasted five days, with two fifteen-minute sessions per day.
The dogs in Groups B & C wore a de-activated collar. That ensured two things: first, that any differences between the groups couldn't be attributed to the physical sensation of wearing a collar, and second, so that observers who coded the videotaped training sessions could not tell to which group any particular dog belonged. In all cases, the dogs were trained to herd a group of sheep.
Equally Effective
A whopping 91.8% of owners reported improvements in their dogs' behavior following training, with no differences across groups, and all were highly satisfied with the results. That suggests that the use of shock collars was no more effective than the use of positive reinforcement alone when it came to improving obedience.
There were no differences between the groups for the amount of corticosteroids in dogs' urine, a physiological marker of stress. When it came to salivary cortisol, Group C dogs were actually highest. While that's perhaps puzzling, it does mean that collars aren't too blame. In addition, when comparing salivary cortisol before and after training none of the groups showed a significant change.
"Overall the physiological data from the main study suggest two things," write the researchers. "Firstly that once the dogs entered training, none of the treatments resulted in large increases in cortisol secretion and by inference arousal or stress; and secondly the differences in salivary cortisol between treatment Groups appear to represent some underlying difference in arousal, perhaps related to time of year, rather than a difference in arousal due to the training programmes."
Welfare Concerns
Beyond that, things don't look too good for those who advocate for shock collars.
While 95 to 100% of owners from Groups B and C indicated that they were comfortable continuing to administer the training program on their own, only 76% of owners from Group A said the same. Among the most important variables in dog training is owner confidence, and an effective program in the hands of an uncomfortable owner is still a recipe for disaster.
In addition, there were some subtle behavioral indications of stress, even in the absence of physiological ones. For example, dogs from both Groups A and B carried their tails lower than those in Group C and displayed more sudden movements away from their trainers. Since these findings applied equally to groups A and B, it is unlikely that they're due to the collars, but rather to the trainers themselves.
Since only four trainers were used in the study, it is impossible to derive clear conclusions. However, the researchers say, "these trainer based differences would be worth further investigation, to examine if they are simply individual differences, or reflect a more general difference in style associated with training philosophy." Those who wore shock collars were also rated as "tense" more often and yawned more, which may be a sign of anxiety.
Taken together, the study paints two broad pictures. One is that neither approach to dog training is more or less effective than the other, in terms of improving obedience and reducing an unwanted behavior, even under the most ideal of circumstances. The second is that despite the lack of physiological indicators of stress, "there are still behavioural differences that are consistent with a more negative experience for dogs trained with e-collars," according to Cooper.
Since training with shock collars was no more effective than without, the tradeoff in terms of animal welfare is – at least in most cases – unacceptable. Even when used in the most optimal way, shock collars are detrimental to the well-being of pet dogs. Imagine how much more a risk they present when implemented by non-expert pet owners.
Read the whole paper in PLoS ONE.
Header image: Scott Butner/Flickr