Buzz
In the summer of 2021, Fingal, Treo, Winnie, and Soot were brought into a room and asked to sniff three different odor samples. These dogs were participating in a scientific study to determine whether they could detect the scent of a stressed human.
It likely comes as no surprise to dog owners: Dogs can definitely tell when their humans are stressed about something.
This research, recently published in the journal PLOS ONE, adds to the growing evidence that dogs can read human emotions. Despite the small sample size—only four dogs and 36 human participants—the dogs accurately identified when breath and sweat samples from stressed individuals (from a tough verbal math test) were present, versus non-stressed control samples. Together, the dogs achieved an impressive 93.8% accuracy rate.
The human participants first provided a baseline sample of their breath and sweat before being tasked with counting backward from 9000 by 17s. Once under pressure, they provided another sample, which was then identified by the dogs—a cocker spaniel, a cockapoo, and two mixed-breeds.
It’s thought that humans release different types of volatile organic compounds (VOCs) depending on their emotional state. Changes in heart rate and blood pressure can lead to shifts in these VOCs, which animals are often able to detect, though humans cannot.
Dogs have long been recognized for their remarkable sense of smell, which allows them to detect everything from drugs to cancer. Prior research has also explored whether dogs can identify emotions like fear or happiness.
This study reinforces what many pet owners have long believed: that dogs can sense when something is wrong and offer comfort, like staying close to their owner or showing signs of concern. However, the study didn’t focus on how the dogs reacted to stress, just their ability to detect it.
Of course, just because a dog is capable of doing something doesn’t mean they will. The study began with 20 dogs, but 16 dropped out due to distractions or boredom.
