It was a novice dog obedience class, where students were preparing their dogs for the first level of formal obedience competition. They were learning the set of exercises which would hopefully lead to a title of Companion Dog, abbreviated as CD. Since a dog show was coming up in a few weeks the instructor was emphasizing some of the nuances of competition.
"It is important for you to remember that in actual competition you can only give one command for each action. That can be either a voice command or a hand signal, but you can't give both."
The woman standing beside a handsome, coal black, German Shepherd Dog interrupted to ask, "Well I suppose that's okay but can you tell me which kinds of commands work better? I've trained her to respond to both my voice and my gestures but which one do you think is more reliable?"
While the question seems like an obvious one, the answer is not. It is one of those issues which can trigger debates that can go on interminably among dog trainers and obedience competitors. From their very basic beginning training sessions most dogs are taught to respond to both our voice and our hand gestures. It just seems as if the combination of a verbal command and a hand signal seems to produce the most reliable performance in dogs especially when they are first learning. But when you have to choose just one form of command, matters become a bit more confusing. Most dog handlers will tell you that which set of instructions you should select depends upon the situation. If you are in a noisy setting then perhaps it is better to use hand signals since your voice command may get lost in the ambient sound. Alternatively, if your dog is looking away and not making direct eye contact with you, it seems reasonable to use a voice command. But what about in those situations where there are no environmental distractions and the dog's attention is directed to you? Do you yell "Down!" or do you raise your hand above your head to signal the dog to drop into a down position? Which command is the dog more likely to promptly obey?
Science often seems to plod along ignoring questions that may provide useful answers while focusing on issues that appear, to the average person, to be of minor importance or seem to address esoteric issues. But the beauty of the scientific enterprise is that sooner or later the data collected in the laboratory will provide answers which have direct application to our understanding of how dogs think and how we should best interact with them. So it was with much pleasure that I encountered an article which has just been accepted for publication in the journal Animal Cognition*. It involved a report by a team of Italian researchers headed by Biagio D’Aniello of the Department of Biology at the University of Naples and it directly addressed the question of the relative efficiency of hand signals versus voice commands.
The subjects of their study were 25 dogs (10 Golden retrievers and 15 Labrador retrievers).. The dogs and their owners were recruited at the Italian School of Water Rescue Dogs, and were already qualified as water rescue teams. These dogs are trained to obey various commands such as: "sit", "lie down", "stay", "come", "fetch", and "turn". The dogs are trained to respond to both voice and hand signals, and this basic training is done on dry land and must be completed so that the dog responds reliably even from a distance, or from behind a wire mesh barrier, before the dogs will be accepted for training for specific water rescue tasks.
For the purposes of this investigation the dogs would receive commands that were given using both the words and gestures that they were normally given during their training. In the first test each dog was given four basic commands delivered by their owner using only hand signals without any verbal information. The second test was the same, except that the four commands were delivered to the dog using voice only, while the owners stood with their hands hanging loosely at their sides.
The final phase of testing was the really clever one. In this condition the hand signals and the voice commands would be incompatible, pitting one against the other to see which one the dog responded to. Thus the verbal command "lie down" was associated with a gesture commanding a "sit"; the verbal command "sit" was accompanied with a signal for "lie down"; the verbal command "come" was accompanied by the gesture indicating "stay" and the verbal command "stay" was paired with a gesture indicating "come".
The results are actually quite clear. In the experimental condition where only the hand gestures were used to issue commands the dogs were remarkably reliable reaching a 99% level of accuracy. In the experimental condition where only the verbal commands were used there was still a high degree of correctness, and for 82% of the trials the dogs responded as they were instructed to do. However, the difference between the dogs' responses to the voice and the signal is quite large and is statistically significant indicating that the dogs were much more reliable when commanded by hand signals.
Now let us turn to the situation where the voice command and the hand signal were put in conflict with each other. Once again the data shows that the gesture dominates over the verbal signal. In 70% of the trials, when the hand signal was pitted against the voice command, the dogs responded to the hand signal. That means that the dogs were more than twice as likely to obey a hand signal when they saw it, even when it conflicted with the verbal information that they were receiving from their handler.
We always knew the dogs were masters of interpreting body language. This makes sense because they have evolved from pack hunters who needed to coordinate their movements. If the leader of the pack spots a deer, for example, and gives the vocal signal which is the canine equivalent of "Hey guys there is a deer over there!" you can be sure that the deer also will hear that sound and will use it as a warning to run for the hills. So canines developed a special sensitivity to reading body language and movement signals of their packmates. There is no reason why this preference should not hold up now that they are domesticated and are interacting with humans. Thus the experimenters summarize their data by saying "In conclusion, our data suggest that, when dogs are equally accustomed to responding to visual and verbal commands, gestural cues are dominant; this supports the evidence that body language plays a major role, being the most important communication channel for dogs." So the take away message is, if there is not some special circumstance and you have to choose between a voice command and a hand signal, you will get a more reliable performance if you use the hand signal to tell your dog what to do.
Stanley Coren is the author of many books including: Gods, Ghosts and Black Dogs; The Wisdom of Dogs; Do Dogs Dream? Born to Bark; The Modern Dog; Why Do Dogs Have Wet Noses? The Pawprints of History; How Dogs Think; How To Speak Dog; Why We Love the Dogs We Do; What Do Dogs Know? The Intelligence of Dogs; Why Does My Dog Act That Way? Understanding Dogs for Dummies; Sleep Thieves; The Left-hander Syndrome
Copyright SC Psychological Enterprises Ltd. May not be reprinted or reposted without permission
Data from: Biagio D’Aniello, Anna Scandurra,Alessandra Alterisio, Paola Valsecchi and Emanuela Prato-Previde (2016).The importance of gestural communication: a study of human–dog communication using incongruent information. Animal Cognition, DOI 10.1007/s10071-016-1010-5