Empathy isn’t just something that humans have. For instance, a person can notice when their friend or partner is under stress and adjust how they act. Interestingly, dogs can do this too! Some animals are trained to help keep people safe, like dogs that alert their owners with epilepsy before they have a seizure. But a recent study reveals that even regular dogs can pick up on human emotions and respond in a helpful way.
Does People’s Stress Affect Dogs’ Behavior?
A recent study found that dogs can detect when people are stressed, which makes them behave more cautiously and sadly. Researchers from the University of Bristol, Cardiff University, and the British charity Medical Detection Dogs worked together on this project. They stressed out human volunteers by making them give surprise speeches and solve tricky math problems, and they collected samples of their breath and sweat before and after these activities.
The scientists studied 36 samples from individuals who said they were feeling more stressed, which also caused their blood pressure and heart rate to rise. They then showed eighteen dogs samples of sweat and breath from the same people when they were relaxed and when they were stressed. Dr. Zoe Parr-Cortes, the main author of the study, explained, “Some researchers have examined whether dogs can really sense different smells. They can! But no one had really explored how this impacts the dogs’ feelings.”
Optimistic or Pessimistic Pups
At the beginning, the scientists put bowls of food in one corner of the room and left the opposite corner with empty bowls. The dogs figured out that they should go straight to the food bowls and started to ignore the empty ones. After that, the researchers changed things up by adding a third bowl in the middle, which was a bit confusing. Parr-Cortes described the experiment. “Will the dogs rush over, thinking there might be food waiting for them, or will they take their time, worried that the bowl might be empty?” Parr-Cortes shared this explanation.
How Dogs Respond to Smelling Stress
Before the dog got its bowl of food, the owner would let it sniff some rags that smelled either stressed or calm. After doing this test several times and changing where the bowl was placed and which rags were used, the researcher discovered that the dogs were more unsure about going to the bowl when it was in a confusing spot after smelling the stressed person. This means the dogs seemed to think there might not be any food there. On the other hand, the smell of a relaxed person didn’t really change their behavior. “This shows that the smell of stress can influence how dogs react in uncertain situations,” Parr-Cortes says. “They might be less willing to take a chance if they think they’ll be let down.”
Evolving Together
The study shows that dogs might believe they won’t get a treat if their owner is upset. Also, if you’re trying to train a dog while you’re stressed, it could hurt how well the dog learns and how it feels. It’s important to note that the dogs in the study were smelling the sweat of people they didn’t know, not their owners or trainers. So, it might be a good idea to train dogs in calm places instead of ones where people feel nervous. Parr-Cortes mentioned that since dogs have been with us for thousands of years, it makes sense they can understand our feelings. This helps them know if there’s something dangerous or stressful around. While humans mostly use their eyes to understand the world, dogs depend on their sense of smell.
“An Olfactory Perspective”
Research like this shows that service dogs can really help people who deal with anxiety, PTSD, and other similar issues. What makes this study special is that it looks at how human feelings can change how dogs see the world around them. The authors point out that if the smell of stressed-out humans can influence a dog’s emotions, how they see rewards, or how well they can learn, it means that stress might not just be passed along through the leash but also through the air. They emphasize that we should think about the training and working spaces for dogs in terms of how they smell.
Sources
- “The odour of an unfamiliar stressed or relaxed person affects dogs’ responses to a cognitive bias test.” Scientific Reports. Z. Parr-Cortes. July 22, 2024.
- “A study finds that dogs can smell your stress — and make decisions accordingly.” NPR. Rachel Treisman. July 23, 2024.
- “Dogs Can Smell Shifts in Human Stress Levels and Adjust Their Behaviors in Response, Study Finds.” People. Kimberlee Speakman. July 24, 2024.