Research suggests dogs can detect stress in humans

According to a new study conducted by Queen's University Belfast researchers, dogs have the ability to detect stress in humans from their sweat and breath. The research findings have been published in PLOS ONE. The study was carried out by Clara Wilson (PhD researcher) and Kerry Campbell (MSc student) in the School of Psychology. They were supervised by Catherine Reeve, with support on collecting the human physiological measures from Zachary Petzel. The study involved four dogs from Belfast - Treo, Fingal, Soot and Winnie - and 36 people. Researchers collected samples of sweat and breath from participants before and after they did a difficult maths problem. They self-reported their stress levels before and after the task and researchers only used samples where the person's blood pressure and heart rate had increased. The dogs were taught how to search a scent line-up and alert researchers to the correct sample. The stress and relaxed samples were then introduced but at this stage, the researchers didn't know if there was an odour difference that dogs could detect.