While cats are generally regarded as being aloof and uncaring, dogs are called "man's best friend." They are in tune with our emotions, it is said. "Lassie" had a level of connection with her humans that only television could write, but there has always been anecdotal evidence that dogs will do whatever they can to help.

A new experiment shows that not only do dogs care if their owner is upset, they will overcome obstacles in a hurry to provide aid. The results in Learning&Behavior showed that dogs with strong bonds to their owners hurried to pushed through a door when they heard their person crying. 

"We found dogs not only sense what their owners are feeling, if a dog knows a way to help them, they'll go through barriers to provide to help them," said lead author Emily Sanford, a graduate student in psychological and brain sciences at Johns Hopkins University. "Every dog owner has a story about coming home from a long day, sitting down for a cry and the dog's right there, licking their face. In a way, this is the science behind that." 


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The experiment involved 34 pet dogs of various breeds and sizes and their owners. Subjects included classic companion dogs like golden retrievers and Labradors, small dogs like shih tzus and pugs, and several mixed breeds. 

One at a time, owners were positioned behind a clear door held shut with magnets. The dogs could see and hear them. While sitting behind the door, the people were asked to either hum "Twinkle, Twinkle Little Star" or cry.

The research team wanted to see if the dogs would open the door more often when their owners cried. That was not the case, but dogs who did open the door when they heard their owner crying opened it three times faster than dogs whose owners were humming.

During the task, the researchers measured the dogs' stress levels. Sanford said dogs who were able to push through the door to "rescue" their owners showed less stress, meaning they were upset by the crying, but not too upset to take action. As for the dogs who didn't push open the door, it wasn't because they didn't care -- it seemed they cared too much. Those dogs showed the most stress and were too troubled by the crying to do anything, Sanford said.

Prior studies have found dogs to be highly responsive to human crying and this showed dogs who detect emotional distress will hurry to do something about it.