Personality traits affecting judgement bias task performance in dogs (Canis familiaris).

Certain personality traits (e.g. anxiousness, fearfulness), are known to affect the cognitive processing of environmental stimuli, such as the judgement of ambiguous stimuli (judgement bias). Our aim was to assess if personality traits are predictive of a more or less 'pessimistic' or 'optimistic' judgement bias in the domestic dog. We assessed dog personality (N = 31) using two validated protocols: the Dog Mentality Assessment (standardised battery test) and the CBARQ (owner-based survey). We used a common task based on the animals' latency to approach a bowl placed in one of three ambiguous positions (Near Positive, Middle, Near Negative) between a baited (Positive) and a non-baited food bowl (Negative) to assess judgement bias. Linear Mixed Model analyses revealed that dogs scoring higher on sociability, excitability and non-social-fear had shorter response latencies to bowls in an ambiguous location, indicating a more 'optimistic' bias. In contrast, dogs scoring higher on separation-related-behaviour and dog-directed-fear/aggression traits were more likely to judge an ambiguous stimulus as leading to a negative outcome, indicating a more 'pessimistic' bias. Results, partially consistent with previous findings in humans, indicate that personality plays a role in the cognitive processing of environmental stimuli in the domestic dog.

Stability of motor bias in the domestic dog, Canis familiaris.

This study explored the relationship between four measures of canine paw preference to establish whether the distribution, direction or strength of motor bias was consistent between tasks. Thirty-two dogs had their paw preferences tested using the Kong ball, tape, lift paw and First-stepping tests. A smaller sample were re-tested 6 months later. The distribution of the dogs' paw preferences was not significantly different from that expected by chance for the Kong ball and lift paw tests; dogs were significantly more inclined towards ambilaterality on the tape and First-stepping tests. More female dogs employed their right paw on the lift paw test; males were more likely to be ambilateral or left-pawed. There was no significant correlation in the direction of dogs' paw use for any tests. The First-stepping and lift paw tests were positively correlated for strength of paw use. Analysis revealed a significant correlation in direction and strength of dogs' paw use between the first and second attempts of all measures, except the tape test. Findings suggest that paw preference in the dog is not consistent between tasks, although stable over time. The study raises questions as to which test of paw preference is the most appropriate to employ.

Cognitive bias and paw preference in the domestic dog (Canis familiaris).

Limb use, an indicator of hemispheric functioning, may be a useful predictor of cognitive bias and hence vulnerability to welfare risk. The relationship between cognitive bias and motor asymmetry, however, has been subject to little investigation. This study explored the association between motor asymmetry and cognitive bias in the domestic dog, a species that displays lateral bias in the form of paw preferences and exhibits positive and negative affective states. Thirty pet dogs had their paw preferences assessed using the Kong ball test. The subjects' affective state was assessed using a cognitive bias test in which the animals' latency to approach a bowl placed in 1 of 3 ambiguous positions was recorded. Animals veering more toward a left-paw preference were found to be significantly slower to approach the bowl placed in 1 of the ambiguous positions than ambilateral or right-pawed dogs. Left-pawed subjects approached the bowl located at the 3 ambiguous positions at roughly the same speed, while ambilateral and right-pawed animals became increasingly slower to approach the bowl the further it was located from the baited food bowl. The study points to a possible relationship between cognitive bias and paw preference in the dog, with left-pawed animals being more negative or "pessimistic" in their cognitive outlook than right-pawed or ambilateral individuals. It is proposed that limb preference testing might offer a more practical and straightforward way of identifying individuals at risk from poor welfare by virtue of how they perceive the world than more time-consuming cognitive bias tests. (PsycINFO Database Record

Association between lateral bias and personality traits in the domestic dog (Canis familiaris).

Behavioral laterality reflects the cerebral functional asymmetry. Measures of laterality have been associated with emotional stress, problem-solving, and personality in some vertebrate species. Thus far, the association between laterality and personality in the domestic dog has been largely overlooked. In this study, we investigated whether lateralized (left or right) and ambilateral dogs differed in their behavioral response to a standardized personality test. The dog's preferred paw to hold a Kong ball filled with food and the first paw used to step-off from a standing position were scored as laterality measures. The Dog Mentality Assessment (DMA) test was used to assess 5 personality traits (e.g., sociability, aggressiveness) and a broader shy-boldness dimension. No differences emerged between left- and right-biased dogs on any personality trait. Instead, ambilateral dogs, scored using the Kong test, scored higher on their playfulness (Z = -1.98, p = .048) and Aggressiveness (Z = -2.10, p = .036) trait scores than did lateralized (irrespective of side) dogs. Also, ambilateral dogs assessed by using the First-Stepping test scored higher than lateralized dogs on the Sociability (Z = -2.83, p = .005) and Shy-Boldness (Z = -2.34, p = .019) trait scores. Overall, we found evidence of a link between canine personality and behavioral laterality, and this was especially true for those traits relating to stronger emotional reactivity, such as aggressiveness, fearfulness, and sociability. (PsycINFO Database Record