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Dogs bring people together. In the days when it was believed that simple possession of a dog might help its owner to live a longer life, it was suggested that these contacts could lead to health-promoting social support. Though this now seems to have been largely illusory, the aura of trustworthiness that dogs confer on their owners remains a robust phenomenon. In my latest book, I argue that this effect can explain the success of some kinds of dog-assisted therapy, the mere presence of the dog instantly creating a bond of trust between therapist and patient.
This “trust effect” has emerged as a common thread in several research studies, conducted in different countries using very different methodologies. The most widely-used scenario involves counting the number of strangers who spontaneously approach a person either standing alone or holding a dog on a leash. Even scruffily-dressed people and potentially scary Rottweilers get people talking. With a well-behaved Labrador at his side, a young Frenchman successfully obtained the phone numbers of about one young lady for every three that he approached. Simply adding the phrase “with a dog” to a (fictitious) man’s on-line dating profile resulted in many more women rating him as a serious marriage prospect – even when the rest of his description revealed him to be uninterested in commitment.
In all of these studies, subjects were reacting to a person to whom the experimenters had assigned the role of owner (or, if you prefer, “guardian”). It's possible, therefore, that the "trust effect" only extends to someone who is evidently in control of a dog. However, earlier this year, researchers at Central Michigan University published a study which suggests that the mere presence of a well-behaved dog can make people more likely to co-operate with one another, even when no one has taken on the role of “owner." (Here’s Marc Bekoff’s take on this study).
The study examined groups of four people (all of them psychology undergraduates) tasked with either creating an advertising campaign (interactive problem-solving) or playing a "prisoner's dilemma" game in which the best outcome for the group was if all four members co-operated. In half of the sessions, one of three dogs—a Jack Russell terrier, a medium-sized mixed breed, or a standard poodle—was present. Probably because the participants were not interacting intensively with the dogs, there were none of the reductions in heart rate or blood pressure that occur when people pet friendly dogs. When the dog was in the room, the subjects did become more co-operative, as measured by expert raters screening videotapes of the sessions.
As in many studies of this type, the dog is visible on the tapes, and it is difficult to be absolutely certain that this has not subtly biased the raters in their perceptions of the subjects' behavior; in other words, the "trust effect" may affect the raters as much as, or even more than, it may affect the subjects. However, in this study, researchers were able to eliminate all sight of the dogs from the tapes by chopping out the lower half of each frame. They then showed clips of the sessions to naive observers, none of whom were able to guess correctly which clips were taken from the dog sessions. And the changes in the subjects' behavior when the dog had been present (though invisible to the raters) were still evident; the individuals were rated as more co-operative, friendly and interactive.
The changes cannot have been due to the presence of the dog "normalizing" the situation, as most likely occurs in some kinds of dog-assisted therapy with the dog helping to make the situation seem "more like home." The study does not report the immediate reaction of the subjects when the dog was introduced into the room, but it is not usual for such "team-building exercises" to involve animals.
Insofar as such setups can serve as proxies for real life — the authors of the study sensibly confined their firmer conclusions to human behavior in the workplace — they do suggest that apparent control ("ownership") is not essential to the effect that dogs can have on reducing social barriers between people. “Pet magic” may be less wide-ranging than its most ardent proposers claim, but it remains a real, if somewhat slippery, concept.
Now that it seems that ownership and control of the animal isn’t essential, the door is open to investigate whether people behave differently toward one another when there’s a cat in the room, though making the cat invisible in the videos might require more than simply cropping the lower half of the frame.
