Dogs who may be experiencing chronic pain show a negative judgement bias
Biased judgement of ambiguous cues as predicting positive or negative outcomes is thought to provide a window into an animals 'affective' or emotional state. Negative judgements of ambiguity have been demonstrated in several species of animal tested in environments assumed to induce negative affect. Here, University of Bristol researchers used judgement bias tests to investigate whether clinical conditions thought to induce pain also generated negative affective states. Many Cavalier King Charles Spaniels have syringomyelia (SM), a neurological condition causing chronic pain in humans, and considered painful in dogs. The researchers found that dogs with this putatively painful chronic condition judged ambiguous cues significantly more negatively than dogs without SM, indicating an association between chronic pain and negative affective state. Although the SM dogs were also receiving medication, there was evidence that SM, rather than medication was associated with the negative cognitive bias. Others measures tested, including sensitivity to a loss in reward, did not show a difference between SM and SM-free dogs. These findings are important for our understanding of pain and for breeding practices in CKCSs. They suggest an affective component to chronic pain, furthering the idea that animals, including dogs, experience pain with an emotional dimension. They also highlight concerns about breeding practices in Cavalier King Charles Spaniels, a breed in which over 70% of dogs experience this apparently unpleasant condition.
Cockburn, A., Smith, M., Rusbridge, C., Fowler, C., Paul, E.S., Murrell, J.C., Blackwell, E.J., Casey, R.A., Whay, H.R. and Mendl, M. (2018) Evidence of negative affective state in Cavalier King Charles Spaniels with syringomyelia. Applied Animal Behaviour Science, Vol 201, p77-84.
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