Humans love receiving a friendly, cuddly greeting from their pup after a long day. But the way that dogs recognize us as we walk through the door is different than the way we recognize our fellow humans. A recent study found that there is a region of the human brain that seems to be specifically designed to recognize other human faces. Scientists were curious if dogs had the same neural signals and used fMRI technology, which is a brain scan that tracks cerebral activity, to study how dogs perceive and understand human facial features. Two groups of dogs were trained to sit through the fMRI scan without moving and were tested on their ability to recognize humans in photos. Researchers compared regular photos of people alongside images that showed scrambled human facial features. They found that dogs had a hard time differentiating vague facial features and a human face.
The study shows that dogs do have the ability to recognize their owners' faces and routines, but only due to time and special training and not out of an inherent instinct. "The dog brain may not have the same tools to process the inner parts of the face (only eyes, nose, mouth)," Dóra Szabó, a graduate student in the ethology department at Eötvös University in Hungary, told TODAY. "The findings are in line with previous behavioral studies, which also reported that dogs cannot recognize their owners based on their inner faces without specific training."
Scientists believe that dogs use a combination of facial recognition, as well as movement and sounds, to recognize their owner. "Dogs are doing fine with getting information from people's faces, they just may not use the same mechanism or brain areas as humans," said Szabó. A more recent study, published just last week in Scientific Reports, looked at how dogs understand human speech signals, sounds, and voice identities. "Dogs live in an environment that is rich in speech and we communicate with them by talking to them," Marianna Boros, a post-doctoral researcher at the neuroethology communication lab at Eötvös University in Hungary, told TODAY. "It is therefore important to understand what elements of speech they can process."
Scientists believe that dogs can understand who is speaking, but don't pay as much attention to specific speech sounds. While both studies can help owners to adjust how they train their dogs, researchers don't think that these studies will drastically change how dogs and humans interact.