Japanese research finds dogs use facial expressions to display emotions A new study has found dogs raise eyebrows when seeing their owners Canines also cock ears when meeting a stranger for the first time Researchers claim expressions reflect brain activity controlling emotions They are universally known as 'man's best friend', but it seems only now are we truly beginning to understand our dogs. New research by animal behavioural experts has found canine emotions are betrayed by specific facial movements, such as raising their eyebrows or cocking their ears. Using high-speed cameras, researchers in Japan found when dogs were reunited with their owners they tended to move their eyebrows upwards around half a second after seeing them. Using high-speed cameras, researchers in Japan found when dogs were reunited with their owners they tended to move their eyebrows upwards, pictured, around half a second after seeing them And when the animals were introduced to someone they had never met before, they moved their left ears back slightly. According to an article in The Telegraph, Dr Miho Nagasawa, from the department of animal science at Azabu University in Sagamihara, said: 'It is difficult to explain this difference in movement between the ears and eyebrows. Dogs" ears are prominent features used to convey emotional expression, therefore our results suggest that dogs were more cautious toward unfamiliar people. In contrast, eyebrow movement might indicate a visible response whereby dogs attempted to look at their owners more intently. The results of the study were published in the journal Behavioural Processes. The researchers placed 12 dogs in a room divided by a partition with curtains that opened briefly to allow the dogs to glimpse what was on the other side, while high-speed cameras tracked their facial expressions. The research also found that dogs raise their left ear when meeting a stranger for the first time and raise their right ear when they see an object they don't like, such as nail clippers What are you thinking? Experts say dogs betray their emotions through a variety of facial expressions Coloured stickers were placed on the dogs' faces, which were picked up by the camera when the expression changed. When the curtain opened, their owner, a stranger, a toy or an item they did not like was on the other side. The researchers found that the dogs moved their eyebrows upwards whenever they saw someone behind the screen, but far more when it was their owner, particularly on the left side. They now believe the changes on different sides of their faces are a reflection of activity in key parts of the brain that control emotions. They also say it could be because the animals were experiencing conflicted emotions - joy at seeing their owner but sadness at not being able to reach them through the partition. Dr Nagasawa said: 'One explanation for this result is that presentation of the owner elicited both negative and positive emotions. A negative response might appear ... perhaps because the dogs could not approach and touch their owners despite seeing them through the partitions. Walkies: This Labradoodle already has his lead on and tongue hanging out in anticipation of going for a stroll in the park Canids are highly social and communicate using an abundant array of facial expressions. These communication methods might play an important role in their communication with humans. Earlier this year psychologists in the United States concluded owners were able to detect emotions in the facial expression of their pets. Dr Tina Bloom, from Walden University, in Minneapolis, found that people could detect happy, sad, surprised and frightened expressions in dogs. Her findings have suggested that humans have developed a natural empathy with dogs after evolving side by side for thousands of years.