WEDNESDAY, June 3, 2020 (HealthDay News) -- Lassie desperately trying to get Timmy out of the well isn't a myth -- your dog really wants to save you, a new study suggests.

"It's a pervasive legend," said researcher Joshua Van Bourg, a graduate student in psychology at Arizona State University in Tempe. "The difficult challenge is figuring out why they do it."

To tease out an answer, Van Bourg's team tried an experiment with 60 pet dogs. None of the animals had been trained to rescue anyone.

For the test, owners were put in a large box with a lightweight door. Once inside, they acted as if they were in distress, calling out "help" or "help me."

"About one-third of the dogs rescued their distressed owner, which doesn't sound too impressive on its own, but really is impressive when you take a closer look," Van Bourg said.

First, a dog had to want to rescue the owner, and then the animal had to figure out how, he said.

In another test, the dogs were encouraged to open a box containing food. Only 19 of the 60 figured out how. More dogs rescued their owners than retrieved the food.

"The fact that two-thirds of the dogs didn't even open the box for food is a pretty strong indication that rescuing requires more than just motivation, there's something else involved, and that's the ability component," Van Bourg said.

"If you look at only those 19 dogs that showed us they were able to open the door in the food test, 84% of them rescued their owners," he added. "So, most dogs want to rescue you, but they need to know how."

In other tests, dogs were more agitated when their owner seemed to be in trouble than if he sat quietly in the box. A lot of the time, the upset isn't necessarily about rescuing, Van Bourg said.

"Most dogs would run into a burning building just because they can't stand to be apart from their owners. How sweet is that? And if they know you're in distress, well, that just ups the ante," he said.

Study co-author Clive Wynne, a professor of psychology, said the study is evidence that dogs really do care about their people.

"The results from the control tests indicate that dogs who fail to rescue their people are unable to understand what to do -- it's not that they don't care about their people," Wynne said.

Even without training, he added, many dogs try to rescue people who appear to be in distress. When they fail, their upset is obvious.

The report was published online recently in the journal PLOS One.

More information

To learn more about dogs helping humans, visit the American Kennel Club.