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You may think your dog can understand you, and in a way, you're right.

New research suggests dogs may actually be smarter than we give them credit for and can also have profoundly positive effects on our health.

Researchers from the University of Sussex in Brighton, U.K., analyzed 42 dogs of different breeds and their reactions to specific words that were not commonly used as commands.

The study, published in the journal Biology Letters , found the dogs could differentiate between slight changes in words spoken by humans and also recognize distinct voices of speakers. (Phonetically similar words like "hid, "heard," or "had," for example.)

As the dogs became more familiar with the language, they only reacted when they heard a new word, which caused them to perk up and refocus their attention.

A new study suggests dogs can recognize distinct changes in words spoken by humans. Max, a border collie who was part of the study, reacts to specific words in the experiment. Credit: Holly Root-Guttridge/University of Sussex 0:41

"They could recognize a word no matter who was speaking," said lead author and animal behaviour researcher Holly Root-Gutteridge.

"And they could also use the same cues to recognize who was speaking and could tell when you changed it on them."

The research concludes that while dogs might not know the actual meaning of a word, they can still identify it — something that was previously thought to be a uniquely human trait.

"It changes our understanding of when human language may have started to evolve," said Root-Gutteridge.

"It's still held up by some people that speech is special, that humans are uniquely able to seize and produce these speech sounds, and that it puts us on this kind of special plateau that nobody else can touch — and it chips away at that.

"Dogs can't produce all of these sounds but they can hear the difference between them."

How smart is your dog?

It's commonly thought that dogs are about as intelligent as the average toddler. But while that's true in some respects, experts say they're actually smarter than infants in certain ways — but less so in others.

"Infants come into this world with abilities that dogs will never have. And in particular, things like language are very human," said Dr. Gregory Berns, a neuroscientist at Emory University in Atlanta.

"Dogs, although they can understand some things, are using different mechanisms than humans do."

For the past eight years, Berns has been training dogs to undergo MRIs and then scanning their brains to understand more about how exactly they think. The research has been published in his 2017 book What It's Like to Be a Dog .

"One thing we find when we look at their brains is they're as different from each other as humans are," he said. "Their brains don't have the neural real estate to produce and process language like humans do, so what they get out of human speech seems to be a much simpler use of words."

While dogs can recognize words that they both have and have not heard before, Berns said he has not found evidence that when they hear a word like "bone," they can conjure up an image of it, like a human can using the visual cortex of the brain.

Though it's commonly thought that dogs are about as smart as toddlers, experts say they process language much differently. (Full disclosure: This is the author's dog.) (Evan Mitsui/CBC)

Another difference Berns found between the brains of humans and dogs is how they give weight to language.

"Human infants come out ready to absorb and name things. The first things they say are 'mama' and 'dada' — those are names of people," he said.

"Dogs may be the other way around. They may actually have very little use for nouns and names, whereas they much more readily learn actions or verbs, which would probably be more important to their daily life."

Think "walk."

What can we learn from dogs?

Dogs may actually help us learn as well.

A recent study published in the journal Anthrozoös from researchers at Brock University and the University of British Columbia (UBC) found therapy dogs may be beneficial in helping motivate kids to read.

They examined the behaviour of 17 students in Grades 1 to 3 in Ontario's Niagara Region while they read a passage slightly above their reading level, both with and without a dog present.

What they found was that kids were more motivated to read when a dog was in the room.

"They were more likely to read for a longer period of time and enjoy it more when the dog was present," said Camille Rousseau, study researcher and doctoral student at UBC Okanagan's school of education.

"Therapy dogs might provide a non-judgmental space and that would allow the children to work through the struggles associated with reading."

A new Canadian study has found kids were more motivated to read when a dog was in the room. (Submitted by the University of British Columbia)

Rousseau said the dog can act as both a comforting presence for the child and an alternate focus of attention. The result is a more positive experience and more exposure to reading as a whole, which contributes to a growth in literacy.

But could a family dog work in helping a child read? It's not exactly clear.

"I wouldn't say just put a dog and a child together [with] a book and just hope for the best," she said. "I think they do have potential, and if parents trust the dogs at home and trust that educational context, I don't see a problem."

Are dogs good for our health?

The short answer is yes, but we don't exactly know why.

An extensive review of 10 studies comprised of almost 70 years worth of research found that owning a dog was linked to a lower risk of death over the long term.

The review, conducted by researchers at the University of Toronto's Mount Sinai Hospital and published in the journal Circulation in October, examined the health information of almost four million people.

They found that dog owners had a 24 per cent lower risk of death from any cause over a followup period of 10 years on average, in comparison with people who didn't own dogs.

And for dog owners who had cardiovascular disease, their risk of death was 65 per cent lower.

"This number is statistically significant and for sure says that somehow dogs are associated with health benefits," said the study's lead author and endocrinologist Dr. Caroline Kramer.

Research shows dogs can also have benefits for people with post traumatic stress disorder and depression by providing emotional support, Kramer said.

"There are also studies suggesting that the presence of a dog can lower blood pressure," she said. "It can be really beneficial.

"So if we look at the whole puzzle, all these pre- and prior studies, plus our analysis, I would say that the evidence is really robust."

Can we help dogs live longer?

While research shows dogs could help lengthen our lives, scientists are trying to return the favour.

The largest-ever study of aging in canines is currently underway in the U.S. and is examining the health patterns of 10,000 dogs.

Five hundred of them will also test a drug called rapamycin that could help them — and ultimately us — live longer.

University of Washington School of Medicine researcher Daniel Promislow, the principal investigator of the Dog Aging Project grant, sits with his elderly dog Frisbee at their home in Seattle. (Elaine Thompson/The Associated Press)

"What we learn will potentially be good for dogs and has great potential to translate to human health," project co-director Daniel Promislow, of the University of Washington School of Medicine, told The Associated Press last month .

The National Institute on Aging is funding the $23 million US project because dogs and humans share the same environment, get the same diseases and dogs' shorter lifespans allow for quicker research results.

But when it comes to our relationship with dogs, how they understand us and what they can teach us, we still have a lot to learn, said neuroscientist Berns.

"A lot of us are very interested in them because of what they are: they're very special in terms of their social abilities and they're quite unique in their ability to form social bonds," he said.

"Because we would all obviously like to have friends and social bonds in the kind of ways that dogs seem to excel at. But we haven't uncovered the secret yet.

"Nobody has."

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