You may not remember what you were doing a few minutes ago. But your dog probably does.
A study of 17 dogs found they could remember and imitate their owners' actions up to an hour later. The results, published Wednesday in Current Biology, suggest that dogs can remember and relive an experience much the way people do.
That's probably not a big surprise to people who own dogs, says Claudia Fugazza, an author of the study and an animal behavior researcher at Eotvos Lorand University in Budapest. Fugazza owns a Czechoslovakian Wolfdog named Velvet.
"Most dog owners at least suspected that dogs can remember events and past experiences," she says.
But demonstrating this ability has been tricky.
Fugazza and her colleagues thought they might be able to test dogs' memory of events using a training method she helped develop called "Do As I Do." It teaches dogs to observe an action performed by their owner, then imitate that action when they hear the command: "Do it."
"If you ask a dog to imitate an action that was demonstrated some time ago," Fugazza says, "then it is something like asking, 'Do you remember what your owner did?' "
In the study, a trained dog would first watch the owner perform some unfamiliar action. In one video the team made, a man strides over to an open umbrella on the floor and taps it with his hand as his dog watches.
Then the dog is led behind a partition that blocks a view of the umbrella. After a minute, the dog is led back out and lies on a mat. Finally, the owner issues the command to imitate: "Do it."
The dog responds by trotting over to the umbrella and tapping it with one paw.
In the study, dogs were consistently able to remember what their owners had done, sometimes up to an hour after the event.
The most likely explanation is that the dogs were doing something people do all the time, Fugazza says. They were remembering an event by mentally traveling back in time and reliving the experience.
Even so, the team stopped short of concluding that dogs have full-fledged episodic memory.
"Episodic memory is traditionally linked to self-awareness," Fugazza says, "and so far there is no evidence of self awareness in dogs and I think there is no method for testing it."
For a long time, scientists thought episodic memory was unique to people. But over the past decade or so, researchers have found evidence for episodic-like memory in a range of species, including birds, monkeys and rats.
Dogs have been a special challenge, though, says Victoria Templer, a behavioral neuroscientist at Providence College.
"They're so tuned into human cues, which can be a good thing," Templer says. "But it also can be a disadvantage and make it very difficult, because we might be cuing dogs when we're totally unaware of it."
The Budapest team did a good job ensuring that dogs were relying on their own memories without getting any unwitting guidance from their owners, says Templer, who wasn't involved in the study.
She says the finding should be useful to scientists who are trying to understand why episodic memory evolved in people. In other words, how has it helped us survive?
One possibility, Templer says, is that we evolved the ability to relive the past in order to imagine the future.
So when we're going to meet a new person, she says, we may use episodic memories of past encounters to predict how the next one might go.
"If I can imagine that I'm going to interact with some individual and that might be dangerous, I'm not going to want to interact with them," she says.
And that could help make sure the genes that allow episodic memories get passed along to the next generation.
STEVE INSKEEP, HOST:
You may not remember what you were doing a few minutes ago, but new research says your dog probably does. NPR's Jon Hamilton reports.
JON HAMILTON, BYLINE: A dog's brain is filled with factual memories - people, places, where to find leftover pizza. But Claudia Fugazza thought dogs might also have what are known as episodic memories - memories of experiences, like chasing a squirrel.
CLAUDIA FUGAZZA: Most dog owners at least suspected that dogs can remember events and past experiences.
HAMILTON: Fugazza herself owns a Czechoslovakian wolfdog named Velvet, but she's also a scientist who studies animal behavior at Eotvos Lorand University in Budapest. And she helped develop a training method that uses dogs' ability to imitate the actions of their owners. Fugazza thought this do-as-I-do training might provide a way to find out whether dogs really do remember events.
FUGAZZA: If you ask a dog to imitate an action that was demonstrated some time ago, then it is something like asking, do you remember what your owner did?
HAMILTON: So Fugazza and other researchers did an experiment with 17 trained dogs and their owners. First, each dog would watch their owner perform some action they'd never seen before. In one video of the study, a dog watches his owner stride to an open umbrella on the floor and give it a whack with his hand. Then the dog is led behind a partition, where he can't see the umbrella, for a minute. When the dog returns, he lies on a mat. Fugazza says this is when an unexpected command will show whether the dog remembers what his owner did.
FUGAZZA: So we ask them to do it.
(SOUNDBITE OF ARCHIVED RECORDING)
UNIDENTIFIED MAN: Do it.
HAMILTON: The dog trots over to the umbrella and taps it with his paw. Fugazza says other dogs did equally well.
FUGAZZA: Despite showing some signs of surprise, the dogs could imitate the previously demonstrated actions.
HAMILTON: Fugazza says this suggests the dogs were taking a mental trip back in time to retrieve a memory. Those memories faded pretty quickly. Even so, they're a lot like the episodic memories people use to chronicle their lives. Fugazza says the team isn't claiming dogs have full-fledged episodic memory.
FUGAZZA: Episodic memory is traditionally linked to self-awareness. And so far, there is no evidence of self-aware in dogs. And I think there is no method for testing it.
HAMILTON: For a long time, scientists thought only people had episodic memories. But Victoria Templer of Providence College says that's changing. In the past decade or so, researchers have found evidence of something like episodic memory in a range of species.
VICTORIA TEMPLER: Magpies, black-capped chickadees, monkeys, rats.
HAMILTON: Templer says dogs presented a special challenge.
TEMPLER: It's difficult to test dogs, right? They're so tuned in to human cues, which can be a good thing. It can be an advantage, but it also can be a disadvantage and make it very difficult because we might be cueing dogs when we're totally unaware of it.
HAMILTON: Templer says the team in Budapest did a good job avoiding that, and the results could help explain why episodic memory evolved in people. Templer says one possibility is that reliving the past helps us imagine the future.
TEMPLER: So if I can imagine that I'm going to interact with some individual and that might be dangerous, I'm not going to want to interact with them.
HAMILTON: A decision that could help a person survive to pass on their genes. The new research on dogs appears in the journal Current Biology.
Jon Hamilton, NPR News. Transcript provided by NPR, Copyright NPR.