Can Brigadoon Service Dogs Sense Human Emotion? - By Angie Hill (2019)
Did you know that humans and dogs share extremely similar social systems? For example, we naturally live as a family (for dogs, this is a pack) which helps each member to look after one another. That’s not all - dogs, as you will know, are very loyal indeed!
We also share similarities by way of body posture, a complex language of facial expressions, and vocalizations that encourage connection with other dogs. Through spending time with humans as domesticated pets which started some 15,000 years ago, canines have developed an ability to decode human nonverbal language.
If you read dog-related websites such as the information available at Woof Dog, you will already know that dogs are incredible at watching and observing. They are far superior to us in this regard and that’s because we focus most of our attention on verbal language and this limits our ability to see what’s going on around us. So, with all the talent that dogs have gained in terms of observation, what do the experts say when it comes to dogs sensing human emotion?
In 2018, researchers at the University of Bari Aldo Moro, Italy, published a study in Springer's Journal Learning and Behavior. The paper’s findings established that dogs have advanced to a level whereby they have specific skills, which developed from living in close contact with humans. This has enabled them to interact and communicate with humans without the use of verbal language.
The authors of the study, Marcello Siniscalchi, Serenella d'Ingeo, and Angelo Quaranta said that during the research they closely observed 26 dogs at feeding times. During these periods the dogs were presented with photographs of the same man and woman, but they were expressing different emotions facially.
The pictures were strategically placed to one side of the dogs’ line of sight, and displayed one of six basic human emotions:
There was also a seventh picture that showed humans displaying a neutral expression.
The findings showed that the canine participants recorded a bigger response and more cardiac activity when they were shown the photographs that had aroused emotional states on them such as happiness, anger and fear.
Furthermore, the dogs took a greater amount of time before eating again and their heart rates had increased which indicates that they’d experienced enhanced stress levels.
The researchers also became aware that the dogs were inclined to turn their head to the right when they saw a non-threatening expression - surprise, for example - but turned their head to the left when shown expressions of happiness, anger, or fear.
The scientists agreed that their findings back-up the existence of an asymmetrical emotional response in the brains of canines that processes human emotions.
Author, Marcello Siniscalchi said: “Clearly arousing, negative emotions seem to be processed by the right hemisphere of a dog's brain, and more positive emotions by the left side.”
Three years before this study, in 2015, Corsin Müller and colleagues at the University of Veterinary Medicine, Vienna published their own research on a similar topic. Müller and the other scientists on his team wanted to determine whether dogs can differentiate between happy and angry expressions in human faces, as opposed to relying on other cues.
In short, their findings were that, yes, dogs can indeed get this information simply by observing our faces alone. Another study in 2016 by a team of animal behavior experts and psychologists from the universities of Lincoln, U.K, and Sao Paulo, Brazil highlighted how dogs can recognize emotions in humans by joining information from different senses.
Seventeen domestic dogs took part in the experiment. Pairs of pictures were revealed to the dogs that showed either a person; one happy, one annoyed. The researchers then played sounds of a person’s voice saying “venha ca” (Portuguese for “come here”) that were in a cheerful or angry tone.
The conclusion was that the dogs typically looked at the picture that correctly matched the tone of voice being played via the audio. They picked out the right human facial expression more often than not.
The researchers effectively showed that dogs form intellectual mental representations of positive and negative emotional states, as opposed to just displaying learned behaviors. Remarkably, canines are the only creatures outside of humans who have been observed to have the ability to do this!
What does this mean? Essentially, these studies have proved that dogs have the capacity to integrate two different sources of sensory information and form a coherent perception of emotion from these sources.
It’s fair to say that we hear many stories from dog owners claiming that their pets can sense the mood of someone in the family. There is a notable difference between associative behavior such as learning to react correctly to a happy tone of voice and being able to tell from a range of very different cues that pair up to signify emotional arousal in another. However, the scientists’ research has proven that, yes, dogs truly do recognize emotions in humans!