Dogs pay more attention to us than previously thought, with new research showing that they remember our actions and other events even when the occurrences didn't hold any particular importance at the time they happened.
The discovery, reported in Current Biology, adds dogs to the short list of other animals — including rats, pigeons and primates — that are known to have what's called "episodic memory." This is opposed to "semantic memory," which is a recollection of facts and rules that an individual knows without the need of remembering a specific event.
"So the difference between episodic and semantic memory can be thought of as the difference between remembering and knowing," lead author Claudia Fugazza of MTA-ELTE Comparative Ethology Research Group in Budapest, Hungary, told Seeker.
People use episodic memory all of the time, she said. For example, if someone asks you, "What did you do first when you woke up this morning?" you could think back to that time, like rewinding video, and play the moment back in your head.
Now it's known that dogs can do something very similar.
The skill is usually tied to self-awareness, so the findings intriguingly hint that dogs could possess that form of cognition too, although Fugazza says it's "extremely challenging to design a study to test for it in dogs."
As it stands, she and her colleagues Ákos Pogány and Ádám Miklósi had to overcome difficulties in testing canine memory skills. They took advantage of a dog trick called "Do as I Do." Dogs trained to "Do as I Do" can watch a person perform an action and then do the action themselves. For example, if their owner jumps in the air and then gives the "Do it!" command, the dog would jump in the air too.
Successfully performing the trick is not enough to prove that a dog has episodic memory, though. That's because they had to demonstrate that dogs remember what they just saw a person do even when they weren't expecting to be asked or rewarded.
To get around this problem, the researchers first trained 17 dogs to imitate human actions with the "Do as I Do" training method. Next, they did another round of training in which dogs were trained to lie down after watching the human action, no matter what it was. Examples included silly things like grabbing a purse covered with dog photos, or touching an umbrella.
After the dogs had learned to lie down reliably, the researchers surprised them by saying "Do It!" and the dogs did what they saw the person do earlier. In other words, the dogs recalled what they'd seen the person do beforehand, even though they had no particular reason to think they'd need to remember.
In addition to showing that dogs have episodic memory, the study is the first "to assess memory of actions performed by others, not by the subjects themselves," Fugazza said, adding that it also suggests dogs remember much of what we do all of the time, "although it may seem irrelevant for them."
"This is a skill," she continued, "that might be useful for a species living in a rich and complex environment where there is so much to discover, and their human companions can be considered as knowledgeable partners to learn from."
Next, she and her team plan to investigate whether dogs understand the goals of others, or if they are just imitating the observed movements, regardless of the goal. They are curious about such matters, Fugazza said, because dogs may prove to be a great model for studying the complexity of episodic memory "especially because of their evolutionary and developmental advantage to live in human social groups."
Originally published on Seeker.
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