When your dog perks up at the sight of their leash or the rustle of their treat bag, its easy to wonder whats going on in their mind? Do they store memories of those sights and sounds, or are their reactions purely instinctive? While much of a dogs behavior is undoubtedly shaped by instinct and training, recent research reveals that some special dogs can recall the names of specific objects for years, adding yet another layer to our understanding of canine cognition.How Dogs RememberMemory in dogs can be divided into two broad categories: short-term memory and long-term memory. Short-term memory is rather limited, lasting only a few minutes. This explains why your pup might seem to forget theyve already greeted you and excitedly return for another round of attention moments later.Long-term memory, on the other hand, involves storing information over extended periods. And although some studies suggest dogs can form and hold onto long-term memories for over a decade, the mechanisms behind this ability remain a topic of research. Researchers generally believe that dogs rely heavily on associative memory, which links events, sounds, or sights with positive or negative outcomes. For instance, your dog might associate the sound of a treat bag with a tasty reward or remember a command like sit due to repeated practice. However, additional research suggests that dogs also have episodic memories, which are memories of previous experiences (the what and where). Read More: How Does Your Dog Understand You?A New Data PointA study recently published in Biology Letters explores whether dogs can retain object-label associations over long periods of time. Researchers previously tested five dogs Max, Rico, Squall, Whisky, and Gaia on their ability to recognize the names of 12 labeled toys taught to them during a one-week training session carried out by the dogs owners. After the initial study, which documented the dogs performance at one, and two months post-introduction, the toys were then removed from their environment for two years.When the toys were reintroduced for the 2024 study, the dogs still demonstrated an impressive ability to recall the objects names, correctly identifying them 44 percent of the time (group average). This performance was significantly above the 20.4 percent chance level expected if the dogs were simply guessing. Furthermore, four of the five dogs recalled and successfully retrieved between three and nine of the toys at least once. These results suggest that at least some dogs can form long-term memories, particularly when it comes to object recognition. Our research has found that even though dogs don't have language, some of them can still remember words, says Shany Dror, lead author of the new study. However, the researchers also caution against generalizing their results to all dogs, as the subjects for the study were specifically chosen based on their reported aptitude for learning the names of objects. As the majority of family dogs do not show behavioral evidence of learning object labels, the study said, the findings presented here cannot be generalized to other dog populations or other cognitive domains.How Does This Compare to Human Memory?While its tempting to project human traits onto our furry companions, its important to remember that their memory functions significantly differently from ours. Humans rely heavily on declarative memory, allowing us to recall explicit facts and events. But, as previously mentioned, much of a dogs memory seems to be more associative they excel at remembering actions and their consequences rather than abstract details.For example, your dog might remember that a certain park is associated with fun walks and interesting smells, but they may not recall the specific day you last visited. This type of memory aligns with their evolutionary history, where survival largely hinged on learning patterns and associations rather than retaining abstract facts.We know that other animals don't share our linguistic abilities, but they do share some of the cognitive abilities that enable us to use language, says Dror. Our hope with this line of research was to start understanding which of these cognitive abilities are shared with animals.Read More: How Many Words Can Dogs Learn?What Does the Research Mean?This concept of long-term memory in dogs isnt new. Take Chaser, a Border Collie often called the "world's smartest dog." Over her lifetime, Chaser learned the names of more than 1,000 objects and could follow complex commands involving verbs and prepositions. Her remarkable skills demonstrated that some dogs clearly possess extraordinary memory and cognitive capabilities.Understanding that dogs can form long-term memories also offers valuable insights for pet owners. For instance, its clear that positive reinforcement is key, as dogs are likely to remember and associate positive actions with rewarding results, such as getting a treat for behaving. Ensuring that your dogs environment is safe, and enriching can likewise have lasting effects on their behavior and well-being.Mental stimulation is also vital for maintaining a dogs cognitive health. So be sure to incorporate activities like training sessions, memory-based games (hiding treats or toys), and exposure to new experiences to help keep their minds sharp as they age.Future ResearchAlthough studies show that dogs clearly have impressive memory capabilities, many questions still remain unanswered. Fortunately, ongoing research into canine cognition could provide deeper insights into the minds of our four-legged friends, in turn revealing broader truths about memory across species. But until then, just remember that the next time your dog wags their tail at the sight of an old toy or eagerly greets a familiar face, you might be witnessing the power of long-term canine memory in action. Article SourcesOur writers at Discovermagazine.com use peer-reviewed studies and high-quality sources for our articles, and our editors review for scientific accuracy and editorial standards. Review the sources used below for this article:Psychology Today. How Permanent Is a Dog's Long-Term Memory?Biology Letters. Dogs with a vocabulary of object labels retain them for at least 2 yearsScientific Reports. Word learning dogs (Canis familiaris) provide an animal model for studying exceptional performanceScience Direct. The role of the hippocampus in recognition memoryAmerican Kennel Club. Remembering Chaser, the Smartest Dog in the World