Why your dog gets so excited to see you

You’ve been away for two weeks on a European vacation, and the moment your dogsitter brings little Monty to the door, your furbaby starts running in circles, squealing, and wagging his tail like a helicopter rotor. Your dog is in the throes of what’s called frenetic random activity periods (FRAPs), otherwise known as “zoomies.” This release of pent-up energy is often a form of happiness and in this case, it’s off the charts. Monty obviously loves you, but seriously—is he OK? 

According to Alison Gerken, a board-certified veterinary behaviorist at the SPCA in San Francisco, California, there are numerous factors that cause your dog to get so excited, and it involves everything from relationship development and neurobiology to emotions and learning.

Dogs form attachment bonds with their caregivers 

Studies show that dogs form attachment bonds, “and those attachment bonds can look a lot like the attachment bonds that human infants develop with caregivers,” says Gerken. “It’s one of the many reasons we often refer to our dogs as our ‘babies.’” In the late 1960s American-Canadian psychologist Mary Ainsworth developed the strange situation procedure, a controlled study that measures an infant’s attachment with their caregiver. 

Researchers later applied the procedure to domesticated dogs and their pet parents—examining how dogs react around their owners as opposed to a stranger. “Results showed that dogs do recognize their pet parent, and they behave really differently with that pet parent upon reunion. This includes a lot more affiliative behaviors,” says Gerken, like nudging or nuzzling. Basically, the same kinds of friendly and positive interactions that facilitate human connections. 

From a Bernese mountain dog greeting a pet parent’s sister to a young boy reunited with his lost dog after a year, there are few things more wholesome than a dog embracing a beloved human. Video: Dogs Reunited With Owners Compilation, Animaldaze

How good is a dog’s memory, and what kinds of things do they remember? 

While the short-term memory of dogs tends to be limited, their long-term memory is impressive—as are the kinds of memories they have. Dogs possess both associate memory, which is the ability to learn and remember the relationships between two unrelated things (such as how your scent equates to playtime and snuggles), and something akin to episodic memory. This type of memory calls up specific events and experiences, such as remembering the previous hiding spot of a tasty treat. 

Dogs can also distinguish between good and bad behaviors, which they learn through processes like classical conditioning and operant conditioning. With the former, dogs can start associating positive meanings to neutral stimuli. The jingling of a collar might mean it’s time to go for a walk, or the sound of keys in a door can signal mom is home. In the case of the latter, a dog will perform a voluntary behavior, such as running in circles or bringing their pet parent a toy, and receive encouraging reactions. For instance, “Oh Monty, you’re such a sweet boy!”

“The dog now knows that these operant behaviors they’re displaying are rewarding,” says Gerken. “So next time, they’ll do it again.”

How does a dog memory work? 

Based on the memories they have of people, dogs then “react to a series of cues,” says Gerken. These cues predict how your furry friend will react when it’s reunited with what it considers its “safe haven, which can really build the emotional process around reunions.”

In 2012, Emory University neuroscientist Dr. Gregory Burns began the Dog Project, a research project that uses function magnetic resonance imagings (FMRIs) to measure which areas of a dog’s brain light up when it’s reunited with its caregiver versus a stranger. (Don’t worry, no dogs were harmed in the study.) According to National Geographic, “The researchers found that the dogs’ caudate nucleus, an area of the brain associated with positive expectations, was most activated by the scent of the familiar person.”

“The first thing that a dog does is smell you,” says Gerken. In fact, their power of scent is incredible. After they smell you, they most likely hear you. “We’ve learned that dogs can distinguish the voices of their pet parents, and not just voices, but also specific words,” like “walk” or “treat.” 

There are also studies that show dogs can distinguish between familiar faces and unfamiliar faces, though their vision isn’t as strong as their smell or their hearing. Your dog probably goes through all of this, and it triggers the memory of how you make them feel and your long history of reinforcing positive experiences.” Once this happens, happy zoomies inevitably ensue. 

The biological role of oxytocin

Oxytocin, a.k.a. “the love hormone,” is a hormone and neuropeptide that plays a big part in fostering feelings of connection and trust between individuals—whether that be a mother and her baby or a dog and their pet parent. 

“Oxytocin is excreted from the hypothalamus in the brain and then gets delivered through the bloodstream,” says Gerken. From there, it ends up in our urine. In 2015, researchers performed a landmark study on what’s called the oxytocin-gaze loop. They asked pet parents to freely interact with their dogs for a period of time and then took urine samples from each party, both before and after their interaction. Researchers found that oxytocin levels were highest when the pet parent and dog were making eye contact with each other. The more the two gazed at each other, the higher their oxytocin levels went. This caused reactions like additional affection and the softening of facial features, creating an ongoing loop of positive reinforcement. 

“Dogs get excited when they see us, secreting oxytocin by both parties and increasing the feel-good vibes,” says Gerken. 

Can a dog tell how long you’ve been gone? 

While dogs can’t read clocks like we can, they do have a sense of time. They also have their own circadian rhythms (internal biological clocks), so they’re pretty in tune with knowing what to expect in their daily routine. Studies have shown that the longer a caretaker is away, the more exuberant a dog’s response at reuniting with them tends to be. 

However, there’s always the chance that if your dog is going wild when it sees you it may be suffering from separation anxiety (a.k.a. separation related disorder), an abnormal response to being left alone. “Think about setting up a webcam and evaluating what your dog looks like when you’re out,” says Gerken. “Look for signs of distress such as pacing, panting, barking, howling, urinating, and defecating that require treatment.” 

Of course, it may simply be that your dog finds life better with you in it, and they’re just really, really, really excited to see you. 

This story is part of Popular Science’s Ask Us Anything series, where we answer your most outlandish, mind-burning questions, from the ordinary to the off-the-wall. Have something you’ve always wanted to know? Ask us.

 

More deals, reviews, and buying guides

The PopSci team has tested hundreds of products and spent thousands of hours trying to find the best gear and gadgets you can buy.