Dogs generally seem to be
cheerful, happy-go-lucky characters, but according to a new study some pooches are distinctly more pessimistic than others.
"This research is exciting because it measures positive and negative emotional states in dogs objectively and non-invasively," said Dr Melissa Starling, from the Faculty of Veterinary Science at the University of Sydney.
"It offers researchers and dog owners an insight into the outlook of dogs and how that changes," she said.
"Finding out as accurately as possible whether a particular dog is optimistic or pessimistic is particularly helpful in the context of working and service dogs and has important implications for animal welfare," she added.
In the study, dogs were taught to associate two different sounds (two octaves apart) with whether they would get the preferred reward of milk or instead get the same amount of water.
Once the dogs learned the discrimination task, they were presented with 'ambiguous' tones.
If dogs responded after ambiguous tones, it showed that they expected good things will happen to them, and they were called optimistic.
Dogs can show how optimistic they are by which tones they respond to, researchers said.
A very optimistic dog may even respond to tones that sound more like those played before water is offered.
"Of the dogs we tested we found more were optimistic than pessimistic but it is too early to say if that is true of the general dog population," said Starling.
However it does mean that both individuals and institutions (kennels, dog minders) can have a much more accurate insight into the emotional make-up of their dogs.
According to the research, a dog with an optimistic personality expects more good things to happen, and less bad things. The dog will take risks and gain access to rewards.
If a dog has a pessimistic personality, it expects less good things to happen and more bad things. This may make it cautious and risk averse.
"Pessimistic dogs appeared to be much more stressed by failing a task than optimistic dogs. They would whine and pace and avoid repeating the task while the optimistic dogs would appear unfazed and continue," said Starling.
"This research could help working dog trainers select dogs best suited to working roles. If we knew how optimistic or pessimistic the best candidates for a working role are, we could test dogs' optimism early and identify good candidates for training for that role.
"A pessimistic dog that avoids risks would be better as a guide dog while an optimistic, persistent dog would be more suited to detecting drugs or explosives," she said.
The research is published in the journal PLOS One.
