"I found that the 'look' appeared most often when owners scolded their dogs, regardless of whether the dog had disobeyed or did something for which they might or should feel guilty. It wasn't 'guilt' but a reaction to the owner that prompted the look," Horowitz said.
"I am not saying that dogs might not feel guilt, just that the 'guilty look' is not an indication of it," she added. She also believes there is a difference between guilt and shame.
Dogs can certainly learn from bad behavior, but rewards or punishment are most effective right after the wrongdoing, said Beaver, the veterinary professor. "The farther it gets from that, the less connection is made with the behavior," she said.
At some point, your dog will probably cower, waiting for you to complete your meltdown, ditch the negative voice and lose the nasty body language, Beaver said.
But you do wonder what other emotions dogs lack besides guilt.
"Humans have a natural desire to know what an animal is thinking, and yet we are limited to reading body language and measuring physiological reactions," Beaver said. The bottom line is: "We will never truly know because we cannot ask them."