So you think you know your dog. But how well does your dog know you? She probably recognizes you when she sees you. But can a dog tell by simply looking at you whether you have a happy or an angry expression on your face? have taught pet dogs to know the difference.
Dogs are very mindful of sound. When dog owners shout or speak in a strong， harsh voice， dogs often act guilty and quietly move away from the area.
Recently， researchers found that dogs can look at our faces， and tell the difference between a smile and a frown. The animals were able to recognize a look of approval from one of disapproval.
Researchers at the University of Veterinary Medicine， Vienna performed a series of experiments. They taught dogs to recognize facial expressions. They showed the dogs two pictures of either the upper or lower half of a person's face. On one picture， the person looked happy. The other appeared angry.
The dogs were then shown images of the eyes or mouths of peo in training.
Corsin Muller led the study.
"We were essentially speaking， do they realize that smiling eyes have the same meaning as a smiling mouth， or angry eyes have the same meaning as an angry mouth? And it turned out that they really did perform very well in these probe trials. Once they had learned the initial discrimination，， immediately choose the correct one also in the probe trials with the normal stimuli."
Once the dogs learned to recognize which image was happy or angry， they could easily identify the same expressions in pictures of any face.
Corsin Muller says future studies will try to show whether dogs can learn the meaning of facial expressions -- for example， whether a frown shows that someone is angry.
"What we can say with our study is that they can discriminate them， that they can tell these ones are different. But what we cannot be sure of at this point is what exact meaning they are associating with these different expressions."
"Seems of course likely that they would associate some positive meaning with the smiley face and they would associate some rather negative meaning with the angry face. But what exactly they are associating with these expressions we cannot know at this point."
In the experiments， researchers found the dogs were slower to link a reward， or prize， with recognition of the angry face. This suggested that dogs had an idea people with angry faces were best avoided.
Corsin Muller says canine investigators are also interested in finding out whether wild wolves can be trained to recognize human facial expressions.
The researchers' findings were published in the journal Current Biology. They provide the first solid evidence that humans are not the only species that can read the body language of another species.
Dogs have been man’ of years， andloyalty since the Stone Age.
they have discovered the root of the relationship - a dog really doesunderstand his master’s voice.
Researchers have found that pet dogs process language in a similar way to humans.
They learn to recognise the words that are spoken -
- theemotional tone， intonation and volume changes that influence the meaning of language.
dogs process language in the same way aswe do.
They tested the way different aspects of language seemed to go through different parts of thebrain.
Humans have a ‘hemispheric bias’， with different aspects oflanguage favouring the left or right side of the brain.
The researchers’ tests suggest that dogs process speech in the same way.