A tired pooch getting some much needed rest.
A team of researchers at Eötvös Loránd University in Hungary performed a small pilot study on 13 dogs, which found that dogs' brains light up when hearing both canine and human noises while asleep. "This finding is significant insofar as it is the first evidence of complex auditory processing during sleep in dogs," Eötvös Loránd University ethnologist Huba Eleőd and colleagues write in their paper.
Now that's one sleepy doggo.
The dogs were connected to apparatuses to record their event-related brain wave reactions while asleep. Then, they were introduced to various vocalizations from dogs and humans while in different states of consciousness: fully awake, semi-conscious, and deep sleep.
The sounds the researchers played were various non-threatening vocal expressions, including yelps, whines and laughter. The researchers were careful not to make any distressing noises that might wake the dog.
Despite being asleep, the researchers found the dogs demonstrated a remarkable ability to discern the source and emotional tone of the sounds — whether dog or human — and detect if the underlying emotion was positive or neutral.
A dog’s ability to understand and process vocalizations while sleeping is much like a human’s. Researchers have found that while humans are asleep, they can differentiate between familiar and unfamiliar voices talking in the background. When people hear a stranger's voice while sleeping, they are more likely to wake up than if it’s someone they know.
Researchers theorize that an unknown voice is more likely to threaten a person’s safety.
A super sleepy doggo takes a nap.
A dog’s ability to recognize other voices while asleep shows they are more like humans than we thought. Eleőd and colleagues believe this similarity between the two species supports the idea that dogs should be used in comparative neurobiology research, which could also teach us more about the human mins as well.
"Although use of a non-invasive ERP paradigm with dogs is quite labor-intensive, it is nevertheless the most feasible possibility to study vocal stimuli processing during sleep, as it does not require prior training and does not cause any distress or harm," the team writes.
This new research not only shows that humans and dogs are even more connected than we knew previously. But it’s also a warning to dog owners everywhere. Be careful not to utter the words “walk” or “treat” around a sleeping dog, or you just may wake them up.
