What every dog owner suspects
Plenty of dog owners will swear their dog knows when they have had a rough day. Instead of the usual zoomies at the door, the dog comes over quietly and leans in. Science has started testing that impression under controlled conditions, separating what we project from what can be measured.
Read also: Why we want to squeeze cute things and Why do we yawn when we see someone else yawn?.
The face and voice experiment
In a study published in Biology Letters, researchers showed dogs photos of happy or angry faces, both human and canine, while playing a cheerful or aggressive voice. The dogs looked longer at the face whose expression matched the tone of the voice. For the authors, that suggests dogs combine visual and auditory information to recognize emotions, including human ones.
Source: Albuquerque et al., Dogs recognize dog and human emotions, Biology Letters, 2016.
Recognizing is not the same as feeling it
Recognizing an emotion is not the same as understanding it the way a person does. Dogs have lived alongside humans for thousands of years and learned to read signals that make that life together work. What the study shows is that reading, not complex thoughts about what we feel.
What a dog does when someone cries
Researchers at the University of London set up a simple test in the homes of 18 dogs. The owner and a stranger took turns talking, humming in an odd way and pretending to cry. The dogs went to the person crying far more often than to the one humming, and they did it even with the stranger, in a submissive posture.
The fact that they approached the stranger suggests they were responding to the emotion, not only to someone they knew. The authors described the behavior as empathy-like, without claiming the dog feels the same thing the person does.
The gaze that bonds
A study published in Science measured oxytocin, a hormone tied to bonding, in dogs and their owners. After a period of looking at each other, levels rose on both sides. When female dogs received oxytocin as a nasal spray, they gazed at their owners longer, and the owners' oxytocin went up too. In wolves raised by people, the effect did not appear.
Source: Nagasawa et al., Oxytocin-gaze positive loop and the coevolution of human-dog bonds, Science, 2015.
What about cats?
Cat people will be glad to know their pets read us too. A team at the University of Bari, in Italy, found that cats can match a person's happy or angry voice with the corresponding facial expression. There are far fewer studies with cats than with dogs, and cats tend to show what they pick up in subtler ways. For another quirk of how we react to animals, see why we want to squeeze cute things.
Source: Quaranta et al., Emotion Recognition in Cats, Animals, 2020.
Sources
- Albuquerque N et al. Dogs recognize dog and human emotions. Biology Letters, 2016. https://doi.org/10.1098/rsbl.2015.0883
- Custance D, Mayer J. Empathic-like responding by domestic dogs (Canis familiaris) to distress in humans: an exploratory study. Animal Cognition, 2012. https://doi.org/10.1007/s10071-012-0510-1
- Nagasawa M et al. Oxytocin-gaze positive loop and the coevolution of human-dog bonds. Science, 2015. https://doi.org/10.1126/science.1261022
- Quaranta A et al. Emotion Recognition in Cats. Animals, 2020. https://doi.org/10.3390/ani10071107
Frequently asked questions
Can my dog tell when I am sad?
Studies show dogs recognize human facial expressions and tones of voice, which helps explain that impression.
Do dogs understand words?
They recognize some words, but mostly they read the tone of voice and the expression of whoever is speaking.
Do cats recognize emotions too?
A 2020 study found cats can match voices and facial expressions, but there is much less research on cats than on dogs.
Why does looking at my dog feel good?
A study in Science found that mutual gazing raises oxytocin, a hormone tied to bonding, in both the dog and the owner.
