December 17, 2014
What's Your Dog Thinking?
Recent findings on canine intelligence and emotions
by Jonathan Balcombe
Because they are social, expressive and responsive to us, domestic dogs have lately become the darlings of research on animal thinking and emotion. During a recent visit to the Clever Dog Lab at the University of Veterinary Medicine in Vienna, Austria, I watched dogs interacting with computer screens or pulling levers with their mouths to deliver food treats. These are not purpose-bred “lab dogs,” but happy pets recruited for the studies.
The Viennese researchers have shown that dogs have a sense of fairness: two dogs, sitting side-by-side, will alternately offer a paw about 20 times to shake hands with a human experimenter. But if one dog gets a treat each time, the jilted dog refuses to offer a paw after about a dozen rounds. In July, Tasmanian researchers documented a related emotion in pet dogs: jealousy. Dogs snapped, pushed and interfered more when the owner displayed affection toward what appeared to be another dog (actually a stuffed dog) but not toward a non-social object (jack-o'-lantern or book).
Clearly, dogs have moods, and it turns out their tail wags contain subtle clues. Italian researchers found that dogs stay relaxed when viewing films of dogs whose tails are wagging predominantly to the right, but they become anxious if the wag is more to the left.
It also behooves a dog to closely monitor our moods and intentions. A 2009 British study found that dogs glance first to the left side of an angry human face but to the right side of a smiling one, which matches how our bilateral brains express negative and positive emotions on our faces.
At Emory University in Atlanta, researchers have monitored brain activity as dogs react to various stimuli. When presented with five scents (self, familiar dog, strange dog, familiar human, strange human), dogs’ brains register the strongest delight in response to the familiar human. It goes to show that the notion of the dog as “man’s best friend” cuts both ways.
Jonathan Balcombe is director of animal sentience for the Humane Society Institute for Science and Policy.