We already knew that dogs are able to detect certain cancers, like breast cancer. Their particularly sensitive sense of smell allows them to detect certain molecules produced by our body. And some studies show that our four-legged friends are sensitive to our emotions.
These researchers wanted to determine if dogs were able to detect a stressed person by their scent alone. For this, they tested two situations: a stressful situation and a neutral situation. To stress the 36 participants, the scientists gave them a mental arithmetic exercise: counting backwards from 9,000 in units of 17, out loud, without the aid of a pen or paper, as quickly as possible and with intimidation of researchers.
Dogs Can Detect Stress Smell With 93% Accuracy
They then had participants sniff out exhaled air from the participants encased in a tube and collected sweat on a compress passed over their necks.
The samples were presented to four dogs, multiple times, in different orders. As a result, after a total of 720 trials, the dogs managed to detect the smell of stress with an accuracy of 93%. Stress is defined as a physiological and psychological response to a difficult situation, whatever it may be, which therefore requires the body to adapt. There is definitely a smell of stress. It should be noted that the sample is small and that we cannot say for the moment which molecule it is. According to the authors, this discovery could help in the training of service dogs, especially for people suffering from post-traumatic stress disorder.