Dogs Hang on Our Every Spoken Word
Dogs might not understand everything we say, but new research shows that they are doing their best to figure us out.
Dogs mull over human speech much the way we do, and they try hard to decipher what we're saying to them, a new study suggests.
The research, published in the journal Current Biology, shows that our dogs are riveted to our words.
Study co-author Victoria Ratcliffe, of the School of Psychology at the University of Sussex, said in a press release that dogs are paying attention "not only to who we are and how we say things, but also to what we say."
Ratcliffe and supervisor David Reby played recorded speech from either side of test-subject dogs, such that the sounds entered each of the dogs' ears, with the same amplitude.
"Although we cannot say how much or in what way dogs understand information in speech from our study," Ratcliffe said, "we can say that dogs react to both verbal and speaker-related information and that these components appear to be processed in different areas of the dog's brain."
It's interesting to note that both dogs and humans provide exterior clues about how their brains are operating when listening to sounds.
"The input from each ear is mainly transmitted to the opposite hemisphere of the brain," Ratcliffe explained. "If one hemisphere is more specialized in processing certain information in the sound, then that information is perceived as coming from the opposite ear."
For example, if a dog turns to its left while it's listening, that indicates the information in the sound is heard more prominently by the left ear, suggesting that the right hemisphere of the brain is more specialized in processing that kind of information.
The researchers observed general biases in the dogs' responses to particular aspects of human speech. When presented with familiar spoken commands, in which the meaningful components of words were made more obvious, dogs showed a left-hemisphere processing bias, as indicated by turning to the right. When the intonation or speaker-related vocal cues were instead exaggerated, dogs showed a significant right-hemisphere bias.
"This is particularly interesting because our results suggest that the processing of speech components in the dog's brain is divided between the two hemispheres in a way that is actually very similar to the way it is separated in the human brain," Reby said.
This is all good news for those of us who enjoy speaking to our dogs and even confiding in them. They may not get everything that's being said, but they usually listen attentively and do their very best to figure us out.
Facial expressions among social animals appear to have universal qualities, to the point where humans and other animals can discern how certain species feel just by looking at their faces. That's the suggestion in two new studies -- published in the Journal of Veterinary Behavior and PLOS ONE -- that help explain how humans can have such close, understanding relationships with animals such as dogs and horses, the subjects of the investigations. The research confirmed, through animal behavioral analysis, the underlying meaning of dog and horse facial expressions and also demonstrated that people have a natural knack for figuring out what they mean. For example, "this dog is experiencing a positive emotional state, as his owner has just come back," Emanuela Dalla Costa told Discovery News. She led both studies and is a researcher in the Department of Veterinary Science and Public Health at the Università degli Studi di Milano. She explained that the dog’s eyes are wide open, as is his mouth, yet his facial muscles are somewhat tense. Together, these features and others suggest that he is happy, eager and hopeful.
Here is another happy dog. In this case, Dalla Costa explained, the dog's "lips are retracted, but with no exposure of the teeth." The dog is thrilled that its owner has just returned and eagerly looks to the human for guidance.
This poor pooch "is tense, due to the departure of his owner," Dalla Costa said. Every part of the dog's face is turned in the direction of his owner's recent exit, maximizing the pup's ability to find him. The dog's eyes and tense mouth convey his worry and loneliness.
This dog's gaze is riveted on its owner, who is holding food. "This emotional condition is considered positive, and we can assume that this dog is happy," said Dalla Costa, adding that "there is no visible tension in the facial muscles." Even though the eyes, ears and face are pointed in one direction, just as they were for the worried and lonely dog in the previous slide, this hopeful canine feels no anxiety.
Every aspect of this dog’s face communicates concern and worry. "The mouth is opened and the dog is panting," Dalla Costa said. "The dog’s lips are partly drawn back, with no teeth exposure. The facial muscles show some degree of tension, visible through ridges that emerge on the lateral side of the face and near the eyes." His ears are up, yet not fully open, an indication that he’s attentive but also worried.
If this dog could talk, the canine would likely be saying, "Oh, please -- feed me." The photo was snapped as the dog looked longingly at its owner, who was holding a favorite food treat. Dalla Costa explained that there is no visible tension in the dog’s face. Its expression cleverly communicates desire and gentleness, while also revealing a sense of hopeful expectation.
Horse expressions, meanwhile, share similar qualities with dogs. This horse, similar to the dogs happily looking at their owners, is attentive and awaiting direction. "The eyes are open and focused on the environment, ears are moving in the direction of sounds, and there is no muscle tension in the mouth," said Dalla Costa.
This unfortunate horse was photographed while in pain, which, thankfully, turned out to be only temporary. In this moment, however, Dalla Costa noted that the horse's ears are in a sideways position. Its eyes are partially closed, and its "chewing muscles are strained and prominent." Even the horse’s nostrils are stiff over its tightly shut mouth.
While perhaps not as uncomfortable as the previous horse, this horse was also photographed while experiencing temporary, minor discomfort. In this case, the horse’s nostrils are wide open, while its lower lip is drawn back. Even its "ears are held passively backward," Dalla Costa said.
This horse is completely relaxed. "There is no tension in the mouth and in the chewing muscles," said Dalla Costa. "The nostrils are relaxed." The horse was happy to be chilling out on a pleasant day in an open field.