It might not be right to give labels like "optimist" or "pessimist" to animals whose perspective is so narrow that every time you feed them, they seem to think they've never eaten before. But researchers in the UK say that a dog's underlying attitude, or cognitive bias, makes it assume better or worse outcomes. And that attitude affects its behavior.
The researchers were specifically interested in anxious behaviors that dogs show when their owners leave. They call this "separation related behavior," or SRB, and it can include howling, whining, destroying things, or "toileting." (Hobbes, the morose black-and-white fellow above, has been known to eat an entire roll of toilet paper when left alone. But I digress.)
To measure dogs' separation related behaviors, the researchers used 24 dogs in shelters. On one day, someone would spend 20 minutes taking the dog to a separate room and hanging out one-on-one. The next day, they'd bring the dog back to the room, play for 10 minutes, and then leave. A camera recorded the dogs for the next five minutes, and their anxious behaviors were tallied to give an overall SRB score. (This test also predicts how a dog will behave in its new home--and shows that a shelter dog will latch on to a person in the blink of an eye.)
A couple days later, the researchers returned to test the dogs' underlying attitudes. In a small room, one person would hold the dog behind a screen while another person set a food bowl all the way to one side of the room. Then they brought the dog out and let it investigate. The dogs quickly learned the trick: if the bowl was against one wall, it held a scoop of food; against the other wall, it was empty. Soon, if the dog saw the bowl against the good wall, it would leap for the food. But if the bowl was on the bad wall, some dogs would amble over slowly to give it a sniff; others, researchers Emily Blackwell says, would "give us a big sigh" and lie down.
Then came the real test: the dog came out from behind the screen to see the bowl in the middle of the room. Sometimes it was closer to the good wall, sometimes closer to the bad wall, and sometimes smack in the center. The researchers wanted to know if the dogs would sprint to the bowl to check for food, wander over slowly, or not even bother. This was the "cognitive bias": did the dogs assume a happy outcome, or a hungry one?
In general, the dogs were slower to get to the food bowl (which was empty) the closer it was to the no-food wall. But when the bowl was in the exact center of the room, some dogs were distinctly slower--that is, more "pessimistic"--than others. And sure enough, these were the dogs with the worst separation behaviors.
Though the researchers point out that "the conscious experience of such a state cannot be known for sure"--who knows what goes on in a dog's head?--they do think that dogs with bad separation behaviors have an underlying negative bias. It could be a genetic component of a dog's personality (animality?), or maybe something they've learned. Dogs learn quickly, and a dog who's in a shelter has already been handed the empty bowl by life.
An anxious shelter dog can still, of course, be an eager and cuddly addition to a home. You just might want to keep him away from the toilet paper.