New research suggests that dogs may remember more than we thought. Any dog owner will tell you that dogs have an uncanny ability to remember things. Whether it be the sound of the garage door opening indicating it is potty-break and dinner time or the opening of the treat jar signaling treat time, dogs consistently illustrate their ability to recount the meaning of specific cues.

New research shows that canines could have a more complex form of memory typically unique to humans that could even indicate a kind of self-awareness. There are two forms of explicit memory (memory used to recall specific information), semantic memory (used to recall information learned or memorized) and episodic memory (used to recall everyday experiences and events). Semantic memory is used to recall words for a vocabulary test where as episodic memory is used to describe to a friend the experience of running a half-marathon last weekend.

The terms semantic and episodic memory were first defined by University of Toronto psychologist Endel Tulving in 1972. Tulving believed the evolution of episodic memory occurred recently and only in human beings. New research in the past few years however, suggests a few non-human animals like chimpanzees, orangutans and bottlenose dolphins may also posses this form of memory. Tulving writes on his faculty webpage, “Many animals – mammals such as mice, squirrels, dogs, elephants, and chimpanzees, as well as most if not all birds – have excellent ‘semantic’ memory. That is, they are capable of conscious learning of facts about the world. However, there exists no evidence that they can mentally travel in time in the same way as humans do, to remember the past and plan for the future.”

Testing for episodic memory in people is relatively straightforward as you can ask one to recall something they didn’t expect to be asked about. Claudia Fugazza is an animal psychologist at Etovos Lorand University and is the lead author of the first episodic memory study of its kind in dogs published in the journal Current Biology. Fugazza’s study suggests that canines may have more advanced memories than we thought.

Since a dog cannot tell you about its memories, Fugazza and her team had to be more creative in their approach. They used distraction to force dogs to rely on their episodic memory by making them recall an unexpected command. Researchers in the study guided seventeen dog owners through six different “Do As I Do” command actions involving a bucket, umbrella and chair. The commands were designed to create an expectation for the dogs in which they were expected to mimic the action demonstrated by their owners. Next the owners distracted the dogs from that expectation by training them instead to simply lie down on a blue carpet following the “Do As I Do” demonstration with the objects. Could the dogs remember the behavior to imitate while expected to just lie down after doing it?

Researchers found that the majority of the dogs were able to correctly remember the action to imitate immediately following the demonstration. Several dogs still remembered the correct behavior to emulate one hour after the demonstration.

Fugazza believes these results indicated the unexpected potential for dogs to have a more complex memory than previously thought. The study also suggests that dogs might be added to the list of valid subjects for future animal psychology studies that traditionally include apes, rats and birds. “We think that dogs are a very good model for studying [animal cognition],” says Fugazza. She further points out the advantage dogs have relative to training and workability in comparison to other study subjects due to the evolution of their domestic nature in the human environment.

Not all scientists, however, are convinced. Victoria Templer is a Providence College neuroscientist in Rhode Island that warns of potential familiarity bias caused by things like the “Clever Hans effect,” where people can unknowingly prompt animals for an answer in experiments. Templer states that this is why she would likely never work with dogs. Templer was not involved in the study.

Templer does nevertheless consider the design and results of Fugazza’s study well done. Moreover, she hopes to see similar work in this field. “It’s one brick in the wall – we need other bricks in the wall to be able to say [for certain] that dogs have episodic memory,” says Templer. For the time being, it is perhaps best to not ask your pet pooch to tell you about yesterday’s vet visit.

This article was adapted from a story featured on Smithsonian.com by Ben Panko titled “Dogs May Possess a Type of Memory Once Considered “Uniquely Human’.”