Letâ€™s say your long-term relationship totally implodes. Browsing for a new apartment, or a therapist, you hear your dog bark in the other room â€” and realise, with a start, that it isnâ€™t actually your dog. Once youâ€™re all moved out, the dog will be out of your life, too.
Stewing in self-pity, you think â€” and subsequently become convinced â€” that this dog, who youâ€™ve fed and bathed who knows how many times, and coined several adorable nicknames for, will forget you ever existed by the start of next autumn.
Probably, for your own health, you should just avoid those kinds of thoughts. Still, the question remains: Are you correct? Can a dog forget one of the people in its life, if that person suddenly leaves it for a long (or long-ish) period of time? To find out, we reached out to a number of experts in canine behaviour, psychology and medicine.
As it turns out, this facet of dog-memory is difficult to study: Systematic research on the subject is close to non-existent. But a vast body of anecdotal evidence suggests that, barring a neurodegenerative illness, your dog will probably never fail to recognise you.
This article was originally published in September 2018.
Lecturer and Coordinator, Companion Animal Cognition Center, Animal Behaviour and Conservation Program, Hunter College
Most pet owners will agree that their pets can remember things. One example: A dog getting excited to head out for a walk after seeing or hearing a leash. Or a dog learning to associate commands with actions â€” sitting when told to sit. These reflect semantic memory, a type of explicit memory, where previously learned information is recalled.
Evidence for semantic memory in animals has been observed across a variety of species. In dog cognition studies, many experimental paradigms utilise a dogâ€™s semantic memory to assess other aspects of their cognitive abilities. However, the question of â€œcan dogs forget their owners?â€ employs another type of explicit memory called episodic memory.
Episodic memory refers to memories of autobiographical events â€” in other words, recalling personal experiences. Endel Tulving, who defined episodic and semantic memory, proposed that conscious recollection was required to demonstrate episodic memory. Given that we have no good way of evaluating consciousness, also known as self-awareness, in animals, it is incredibly challenging to suggest that dogs, or other animals, have episodic memory.
To get around this definitional constraint, researchers have separated the behavioural criteria required for episodic memory from the conscious component and termed this â€œepisodic-likeâ€ memory. Using this definition, animal behaviour researchers can now evaluate whether or not animals behaviourally demonstrate the recalling of autobiographical events.
To date, there is evidence that some non-human animals, such as great apes, dolphins and scrub jays may possess some form of episodic-like memory. But how about our dogs? Are they capable of episodic-like memory? Can they remember us â€” or forget us?
In a 2016 study, Claudia Fugazza and colleagues evaluated episodic-like memory in dogs. The results suggest that dogs can recall their ownerâ€™s actions, even in instances in which they were not explicitly commanded to do so. These findings indicate that dogs may have episodic-like memory in which memories are linked to specific times and places.
While we may not yet know the answer to â€œcan dogs forget their owners?â€, it seems plausible that the evidence for episodic-like memory, in the form of memories related to time and space, may extend to remembering things like â€œwhoâ€. We need more research to uncover the answer to this question, but for now, itâ€™s nice to come home to a dog, that in our mind, appears happy to see us.
Professor, Psychology, Brooklyn College and the CUNY Graduate Center, and Guest Professor at Stockholm University, whose research focuses on animal learning and memory
Many animals have excellent long-term memory. A long-term memory, as the name suggests, can remain intact without significant degradation for years.
Anecdotes about pets recognising their first owner, or another significant person in their life, after many years are supported by experiments on animal memory, in which animals have been trained to identify images and then had their memory tested months or even years later. In fact, even pigeons, who are not considered overly intelligent by lay people, can remember hundreds of images for many months.
The question is more whether the memory is formed in the first place than whether it will be remembered, once formed. For the most part, animals form long-term memories of events and situations that they deem meaningful.
If a person is particularly mean to the animal, they might form right away a very strong aversive memory, and thereafter react with fear or aggression. If a person forges a long term bond through daily, positive interactions, that person will likewise be remembered for many years. I am not positive that casual acquaintances will be remembered as well.
Memories of other beings (animal or human) are more easily formed in social animals, such as dogs, horses or parrots. Cats are more solitary and therefore they do not feel strongly about the mere presence of other beings. At the same time, itâ€™s hard to imagine that extensive positive interaction will not form a memory at all. Moreover, because they are less social, cats are also less expressive of their emotions, so they might still remember someone but not be very vocal about it.
Iâ€™m afraid this will be another point of argument between dog people and cat people.
Assistant Professor, Psychology, Rollins College, with research interests in human and non-human decision making, impulsivity, risk taking, and animal behaviour
Forgetting, remembering, love and attachment. These words describe the human experience of finding pleasure in another. Sometimes when we are away from the other person, we think about them, and then we experience joy at seeing them once again. For people, these processes involve language, which enables us to handle abstract concepts and talk about events that happened in the past.
For dogs, there is no evidence that they have this internal monologue. Fortunately, learning can also involve non-language associations between events, such as when we associate a smell with a pleasant occurrence, or when we start spending more time with someone because they make us feel good. These associations can happen without our being able to describe what is happening, and they can last our entire lives with only a few initial experiences.
These associative processes (respondent and operant conditioning) are how dogs learn.
Sometimes these associations do not serve us well in our daily lives; we seek to forget painful or irrelevant associations. One way to forget is to undergo counterconditioning, or systematic desensitisation. Associations can also break over the passage of time, if we go without exposure to relevant cues.
For all of us, the durable nature of associations with others is a double-edged sword. For example, a dog might respond to a previous caregiver they havenâ€™t seen in years with exuberant butt-wiggling, and a dogâ€™s fear of men in baseball caps might also endure for years.
Animal shelter staff and volunteers are familiar with the counterconditioning process in which they overcome a dogâ€™s negative experiences with people in the past by creating a new association: People equal treats/toys/good times. For a dog with a lot of negative past experiences, this process is slow and deliberate, and the trainer minimises threatening stimuli by introducing new things carefully. Dogs, like people, learn best when theyâ€™re calm.
In time, and with the trainerâ€™s skill, the past is less influential on the dogâ€™s behaviour, and the dog learns that people are fun. For dogs with positive past experiences, these associations with their previous owner also fade over time as new sources of treats and cuddles arise.
So, yes, dogs can forget. While the idea that our pet could forget about us may be disappointing, this ability to forget is actually something that we admire most about dogs: They donâ€™t hold grudges, and they are remarkably adaptable to their current settings. Without the internal language processes of pondering, rumination, obsession and analysis, they live in a simpler world of forgiveness and new beginnings.
Professor, Human-Animal Interactions and Behaviour, UC Davis School of Veterinary Medicine
There are no controlled studies of this that come to mind. However, the greeting behaviour of dogs is consistent, and a feature viewed by owners as a characteristic of a perfect dog â€” and dog owners rate their dogs as excellent on this trait. Itâ€™s an example of built-in compatibility and shows that dogs recognise their people.
However, as dogs age some have cognitive deficits and no longer recognise their owners, which can be very distressing. Long term caregivers of elephants sometimes have not seen the elephant for even decades and then been fully recognised by the elephant.
Professor, Psychology, Brown University, specialising in animal learning and behaviour, particularly in dogs
College students going home for winter break will undoubtedly be greeted ecstatically by the canine sibling they left behind and feel reassured that they were not forgotten.
Such were the experiences described by the Nobel prizewinning ethologist Konrad Lorenz in his insightful book Man Meets Dog. For example, returning home after nine months, Lorenz describes how Stasi first catches his scent, then howls deliriously for more than a minute before bounding and leaping towards him in frenzied excitement. The intensity of her welcome is hard to explain in any way other than that she recognised her owner.
But might a dog forget her absentee pack member after a longer separation? It seems unlikely for a number of reasons. Odour memories appear to be extremely robust and long-lasting. The French writer Marcel Proust famously describes the evocative power of the scent of a Madeleine biscuit soaked in tea to transport him back in time to his auntâ€™s kitchen.
With a nose and brain built to process olfactory stimuli, a dog is not likely to forget what scents mean, especially when they belong to members of their family and have strong emotional connections. Additionally, contextual cues are known to aid memory retrieval, which would facilitate the dogâ€™s ability to recognise the odour walking through the front door.
But there may be an exception. Like humans, dogs are living longer; and, like humans, they can develop symptoms of dementia. A dog with canine cognitive dysfunction might forget his owner, but how would we really know? The lack of a response can be very difficult to interpret.
Professor Emeritus, Clinical Sciences, Tufts University, founder of the Animal Behaviour Clinic and author of many books, including Pets on the Couch: Neurotic Dogs, Compulsive Cats, Anxious Birds, and the New Science of Animal Psychiatry
Canine Alzheimerâ€™s is definitely a real condition. I do call it Canine Alzheimerâ€™s â€” the purists will say, â€œwell, itâ€™s not exactly the same,â€ but it kind of is exactly the same, right down to the changes that occur in the brain.
In humans with Alzheimerâ€™s, thereâ€™s a build-up in the brain of a protein called amyloid. (Thereâ€™s another protein involved, but amyloid is the main culprit.) The degree to which the brain is affected correlates precisely with the degree of psychomotor impairment in the person, and the same is true in dogs.
One of the cardinal signs of Alzheimerâ€™s is disorientation, and disorientation involves not recognising familiar people. So disease can cause it, and I imagine there are other neurological conditions that could as well.
But you look at all the videos on YouTube of soldiers whoâ€™ve been away in various theatres of war for long periods of time â€” they return and the pet goes absolutely ballistic.
Or think of the famous story of Greyfriars Bobby in Edinburgh, Scotland â€” this was a dog whose owner died and was interred in a church graveyard, and apparently the dog spent the next nine or 10 years just sitting on the grave, waiting for his master to come back.
And there was a Japanese dog who always met his owner off the train at a certain time, and who still went down to meet the train for years after the owner died of a heart attack, hoping he would get off.
These stories sort of confirm that dogs have incredibly long memories for people theyâ€™re fond of. And with people theyâ€™re fond of, they remember everything about them â€” every nuance, from appearance to smell. All their sense are acutely tuned to that person.
Professor and Area Head, Behavioural Neuroscience, Arizona State University and head of the Canine Science Collaboratory
Darwin, when he went around the world on the Beagle, was very impressed by the fact that when he got home four years later his dog clearly recognised him. And plenty of less famous people than Darwin have had the same experience.
But as for the reverse â€” cases where people were away from their dog for some period of time, and the dog did not recognise them when they returns â€” I cannot think of any instance where that happened. Itâ€™s one of those things that might have happened, but nobody would want to boast about it.
But just because dogs remember their people for years doesnâ€™t mean itâ€™s cruel to rehome a dog.
I feel very strongly that more people should be adopting older dogs, or dogs from shelters, as opposed to thinking you have to have a puppy â€” thinking that you wont really have a loving animal if you didnâ€™t know the dog when it was a puppy. And thatâ€™s just not true. Dogs can form strong emotional bonds with people even if they donâ€™t meet those people until considerably later in their lives.