Researchers have long argued that most dogs respond to human emotion in words, and not the actual meaning of words. But now a scientist has demonstrated otherwise.

In fact, researcher Victoria Radcliffe of the University of Sussex in England has revealed that dogs respond to both emotion and meaning when their humans speak.

To prove it she sent identical commands through speakers on either side of a dog's head. Then she manipulated the messages, in some cases removing all emotion from a command, in others turning the words into gibberish.

When dogs heard commands with meaningful words, about 80 percent of them turned to the right. When they heard commands with just emotional cues, most dogs turned to the left.

The experiment shows that dogs can differentiate between actual words and gibberish, notes Radcliffe, because when the words didn't make sense, they sought out emotional cues.

It also indicates that dogs process speech into two parts and use different hemispheres of the brain to determine either emotional cues or the meaning of words, a bit like humans, she explains. Emotional cues are processed on the right side of the brain, and the meaning of words on the left — the opposite of the way the dogs turned.

Word to the wise? Pick the right ear for the right impact in a dog.

"Tell all the emotional things to the dog in his left ear," neurobiologist Attila Andics of the MTA-ELTE Comparative Ethology Research Group in Budapest tells NPR. "For commands that you want a dog to get clearly and precisely, tell them in right ear."