March 19, 2014
Scent Of A Dog Owner
For dog owners, the moment when they walk in the door and receive the love and affection from their dogs is precious. Immediately, a beloved dog responds with happiness when she sees her pet parent. When a dog hears her owner, her tail wags and obvious love cues kick in. However, sight and sound are not the only senses that produce such a loving and happy response in dogs. As redOrbit reported, dogs know their people by scent as well.
In a study led by Gregory Berns, director of Emory University’s Center for Neuropolicy, the researchers found that the way owners smell likely lingers on the dog’s brain like perfume. Twelve dogs from a variety of breeds underwent fMRI scans because they had been trained to hold perfectly still while experiencing the scan. As redOrbit explains, “While the dogs were being scanned, researchers presented the subjects with five different scents that had been collected on sterile gauze pads that morning and sealed in Mylar envelopes. The scent samples came from the subject itself, a dog the subject had never met, a dog that lived in the subject’s household, a human the dog had never met, and a human that lived in the subject’s household.”
Though all the scents used in the study stimulated similar responses in parts of the dogs’ brains, the caudate responses where significantly stronger for the smell of the familiar humans. This response leads researchers to believe that the dogs both recognized the familiar human scent – or at least discriminated it – as well as had positive associations toward it. As redOrbit’s Lee Rannals writes, “’It’s one thing when you come home and your dog sees you and jumps on you and licks you and knows that good things are about to happen,’ Berns says. ‘In our experiment, however, the scent donors were not physically present. That means the canine brain responses were being triggered by something distant in space and time. It shows that dogs’ brains have these mental representations of us that persist when we’re not there.’”
So it seems that dogs recognize their owners by sight, sound, and smell, each of which brings them a positive reaction, which manifests itself in voluntary actions such as jumping, licking, tail wagging, and even barking. These findings show just how connected dogs are to their humans. Simply smelling a familiar human elicits happiness and love in dogs, which is pretty cool.
What is even cooler is where further research may take this. Berns explained that future research will focus on determining whether brain-imaging techniques can be used to better identify dogs most suited to serve as companion animals for the disabled as well as serve as therapy dogs.
As a lifetime dog parent, I have always understood my dogs ‘know’ me. For a long time, I assumed it was simply by sight or sound. Now, though, I know that my scent is just as powerful in creating a happy response as all the other senses. With how important dogs are in many people’s lives, it is good to know just how their brains work to connect them to us. And, honestly, it is nice to know that they love everything about us, even our scents.
Image Credit: Thinkstock