You’ve probably heard the phrase that animals – especially dogs – can “sense fear” as if it were a sixth sense. You might have even experienced it yourself if you’ve ever felt nervous dropping your pet off at the dog sitter or an overnight dog boarding service, and suddenly your normally calm dog starts acting on edge. On the flip side of that, when you’re happy to go to the doggie lodge, your pet seems to mimic your emotions, and it’s an easy drop-off.
(Pixabay / jarmoluk)
While dogs don’t “technically” have a sixth sense, they can understand human emotions really well through their fine-tuned five senses.
In fact, researchers have discovered that dogs can read human emotions using their sight, smell, and hearing, meaning that dogs can know when you’re happy or upset without even needing to see your beautiful face.
Fear by Any Other Name Wouldn’t Smell as Sweet
One group of researchers published a study in the pet publication Animal Cognition in 2017, where they analyzed how well dogs responded to the smells of “emotional sweat.” In the experiment, researchers had male test subjects watch a 25-minute video that produced happy emotions one week and fearful emotions the second week. Both weeks the test subjects abstained from eating smelly food or wearing any scented hygiene products for a few days before. After watching the video, the researchers absorbed the sweat that the test subjects produced using small pads.
During the trials, dogs were randomly assigned to either a happy, sad, or control (no smell) room. In the room, there was a stranger (not the original test subject) and the dog’s owner. The dog wore a heart rate monitor, and the whole interaction was taped so that researchers could analyze behaviors later.
After the initial “settling in” period in the room, the researchers started the experiment by introducing the scent, and the stranger and owner began reading a newspaper and couldn’t interact with the dog anymore. Researchers measured the different types of behaviors according to the scent that was in the room, and they found some interesting results.
For the rooms with fear scents, the dogs became more agitated, had higher heart rates, and tried harder to get their owners’ attention and affection. In the happy rooms, however, the dogs remained playful and wanted to engage with the stranger more.
Researchers admit that they need to do more testing on different breeds, but the current evidence suggests that humans produce smells based on their emotions, and dogs can distinguish and react to those smells predictably.
Emotion in the Eye of the Beholder
In a 2015 study published by Current Biology, researchers tested whether dogs could distinguish emotions based on seeing only part of a human face. The researchers started by training the dogs to touch a specific stimulus when they saw a happy or angry face.
They then showed the dogs only the top, bottom, or left half of an angry and happy face, and the dog was rewarded with a treat if they chose correctly according to the prompt. The research found that happy faces yielded the fastest responses, and dogs with angry-faced prompts were slower to respond – likely because dogs tend to shy away from contention.
Sounds About Right
In 2016, a group of researchers in Brazil and England published an article showing the results of their experiment that studied how well dogs paired up sounds with facial expressions.
In the study, they showed a dog either a human or dog face and played a sound made by a human or dog, respectively, at the same time. The researchers projected the same person’s face on two different screens, but one face was happy and the other was angry. They would then play a noise that was either brown noise (neutral), happy, or angry. To make sure that language understanding didn’t influence the results, the researchers had the human sounds be from a language that the dog’s owners didn’t use at home.
They found that a majority of the time, dogs looked significantly longer at a face that matched the sound they heard over the speaker. When the brown noise was played, the dogs didn’t look at one picture over the other. These results suggest that dogs understand the relationship between facial expressions and the emotions that accompany them.
Scientists and researchers are conducting more experiments all the time to try and crack the code for how dogs understand human behavior. All studies have variables and limitations that make it impossible to conclude anything with 100{a28d9fe88b019108ba10d93acd408de466e38e0ac6414dac18ed747bab797210} certainty, but the research in these studies provides some pretty solid evidence that dogs can sense human emotions in more ways than one. No wonder they make such incredible companions!
