"Who's My Good Doggie?"

Hungarian researchers reported in a study last year that a guide dog for a blind and epileptic person became anxious before its master suffered a seizure and was taught to bark and lick the owner’s face and upper arm when it detected an onset, three to five minutes before the seizure. It is still somewhat mysterious how exactly dogs detect seizures, whether it’s by picking up on behavioral changes or smelling something awry, but several small studies have shown that a powerful sense of smell can detect lung and other types of cancer, as the dogs sniff out odors emitted by the disease.

Beyond these perceptual abilities, in which trainers can use the dogs’ natural instincts, some research has examined dogs’ actual cognitive ability, and found not just good doggie, but smart doggie.

“I believe that so much research has come out lately suggesting that we may have underestimated certain aspects of the mental ability of dogs that even the most hardened cynic has to think twice before rejecting the possibilities,” said Stanley Coren, a psychology professor at the University of British Columbia and an author of several books on dogs.

Dr. Coren’s work on intelligence, along with other research suggesting that the canine brain processes information something like the way people do, has drawn criticism. And there is good reason. For most of the last century the specter of a horse named Clever Hans hung over anyone who tried to prove that dogs were acting in thoughtful ways — not merely mimicking or manipulating people into believing that they in fact grasped human concepts.

Clever Hans was said to be able to count, make change and tell time by tapping his hoof, until investigators in the early 1900s learned that Hans was merely responding to his trainer’s body language, tapping when the trainer nodded his head. This provided an enduring example for those who believed thought was the exclusive domain of humans.

But in 2004, German researchers reported that a border collie named Rico could learn the name of an object in one try, had 200 objects in his repertoire and remembered them all a month later, all very human. Even skeptical animal behavior researchers found the Rico results impressive and sound. Is it possible that Rico turned the tide on the Clever Hans problem, even though there is debate about how we can reliably measure what dogs know?

By giving dogs language learning and other tests devised for infants and toddlers, Dr. Coren has come up with an intelligence ranking of 100 breeds, with border collies at No. 1. He says the most intelligent breeds (poodles, retrievers, Labradors and shepherds) can learn as many as 250 words, signs and signals, while the others can learn 165. The average dog is about as intellectually advanced as a 2- to 2-and-a-half-year-old child, he has concluded, with an ability to understand some abstract concepts. For example, the animal can get “the idea of being a dog” by differentiating photographs with dogs in them from photographs without dogs.

[http://www.nytimes.com/2009/11/01/weekinreview/01kershaw.html?em]