We often say the same sweet, nonsensical things to our dogs that we say to our babies—and in almost the same slow, high-pitched voice. Now, scientists have shown that puppies find our pooch-directed speech exciting, whereas older dogs are somewhat indifferent. The findings show, for the first time, that young dogs respond to this way of talking, and that it may help them learn words—as such talk does with human babies.
To find out how dogs reacted to human speech, Nicolas Mathevon, a bioacoustician at the University of Lyon in Saint Étienne, France, and his colleagues first recorded the voices of 30 women as they looked at a dog’s photograph and read from a script, “Hi! Hello cutie! Who’s a good boy? Come here! Good boy! Yes! Come here sweetie pie! What a good boy!” (The scientists were afraid the women would ad lib if they spoke to a real dog.) The women also repeated the passage to a person.
When the scientists compared the human- and dog-directed speech, they found that, as expected, the women spoke in distinctive, high-pitched, sing-song tones to the pooches—but not the humans. “It didn’t matter if it was a puppy or an adult dog,” Mathevon says. But the women did speak at an even higher pitch when looking at puppy photos.
Next, the researchers played these recordings in short trials with 10 puppies and 10 adult dogs at a New York City animal shelter and videotaped their responses. Nine of the puppies reacted strongly, barking and running toward the loudspeaker even when the recording had been made for an older dog, the team reports today in the Proceedings of the Royal Society B. Some even bent toward the loudspeaker in a play bow, a pose meant to initiate horseplay, suggesting they may regard dog-directed speech as “an invitation to play,” Mathevon says. The puppies were less interested in the recordings of the women speaking to the person. And the adult dogs? “They didn’t care at all,” Mathevon says. It made no difference if they heard speech directed at puppies, older dogs, or humans. “They had a quick look at the speaker, and then ignored it.”
The scientists aren’t sure why the adult dogs were so disinterested. It may be that they need to interact with an actual person, not a disembodied voice, or that they need to hear a familiar voice, Mathevon says. But for the puppies, the women’s exaggerated, high-pitched, dog-directed speech served a purpose: “It got their attention,” says Mathevon, who thinks this way of talking may help them learn words, just as our baby talk helps human infants learn language. Other research, however, disputes this idea.
Still, the study shows that even in our speech “we care for and treat dogs of all ages like human infants,” which is likely “an important part of their success in human environments,” says Monique Udell, an animal behaviorist at Oregon State University in Corvallis who was not involved with the work.
The scientists don’t yet know whether puppies have an innate response to dog-directed speech or whether it is something they learn. It will also take further study to figure out whether the words in dog-directed speech mean something more to the puppies, or whether it helps them learn words. In the meantime, when you speak doggy to your puppy, be sure you’re ready to play.