Researchers at Queen’s University Belfast have found that dogs are able to pick up stress in humans through volatile organic compounds in their breath and sweat. They can detect the difference in the breath and sweat of people who are stressed and calm. Clara Wilson, the lead author said: “The research highlights that dogs do not need visual or audio cues to pick up on human stress. This is the first study of its kind, and it provides evidence that dogs can smell stress from breath and sweat alone, which could be useful when training service dogs and therapy dogs.”
We’ve known that dogs can pick up stress in humans but until this study it wasn’t clear exactly how they achieved it.
So now we know it’s all about odour and the dog’s fantastic sense of smell which is unsurprising. For the test they recruited four pets from Belfast: a cocker spaniel (Treo), a lurcher (Fingal), a terrier-type mixed breed (Soot) and a cockapoo (Winnie). They collected samples of sweat and breath from 36 people both before and after they were stressed. They were stressed out by a maths problem that was difficult to solve!
When the dogs were presented with the two samples from the same person, they were consistently able to pick out the sample that was produced when they were stressed.
The researchers believe that the findings could allow dogs to be trained to help people with conditions such as anxiety disorders and post-traumatic stress disorder (PTSD).
At the moment therapy dogs are trained to pick up on visual clues such as watching out for the person putting their heads in their hands or some other form of human behaviour which indicates stress and distress.
Relying on the odour of sweat and breath may allow dogs to pick up signs of stress much earlier. Therapy dogs trained to do this could also be trained to fetch medication or calm their owner in other ways such as sitting with them.
There is also a technique called “interrupting anxiety” in which dogs are trained to lick their owner’s face to catch their attention. This helps stop negative moods developing and spiralling out of control.
Dogs can also detect explosives as we know and diseases such as malaria and cancer.
A charity, Medical Detection Dogs, places dogs with people with life-threatening conditions. The dog companions can detect tiny changes in odour which then signals an emergency.
On the possible downside, some researchers believe that training dogs to recognise people who are struggling and who are stressed might affect the dog negatively. That’s quite a good point. Are humans ‘leaning’ on dogs to the detriment of the dog? When a dog picks up stress in their owner, do they themselves become stressed? This seems highly plausible. In which case, is this a mild form of dog abuse? That’s a philosophical question.
Anatomy: The humble dog companion has an area above the mouth called the ‘olfactory recess’ which is a labyrinth of thin bones that trap odours. The ‘olfactory bulb’ processes these odours in the brain. The nostrils are moist which helps to capture scents. And the dog’s ‘vomeronasal organ’ detects hormones in humans while the lamina transversa divides the airway into two sections, one for smelling and one for breathing.
Below are some more articles on dog sesnes.
