1,720,972 research outputs found
The dog nose 'KNOWS' fear: Asymmetric nostril use during sniffing at canine and human emotional stimuli
No full textPrevious studies have reported striking asymmetries in the nostril use of dogs during sniffing at different emotive stimuli. Here we report, for the first time, that this asymmetry is also manifested during sniffing of both human and canine odours collected during different emotional events. Results showed that during sniffing of conspecific odour collected during a stressful situation (e.g. an "isolation" situation in which a dog was isolated from its owner in an unfamiliar environment) dogs consistently used their right nostril (right hemisphere). On the other hand, dogs consistently used the left nostril to sniff human odours collected during fearful situations (emotion-eliciting movies) and physical stress, suggesting the prevalent activation of the left hemisphere. The opposite bias shown in nostril use during sniffing at canine versus human odours suggests that chemosignals communicate conspecific and heterospecific emotional cues using different sensory pathways
Relationship between visuospatial attention and paw preference in dogs
Full text linkThe relationship between visuospatial attention and paw preference was investigated in domestic dogs. Visuospatial attention was evaluated using a food detection task that closely matches the so-called "cancellation" task used in human studies. Paw preference was estimated by quantifying the dog's use of forepaws to hold a puzzle feeder device (namely the "Kong") while eating its content. Results clearly revealed a strong relationship between visuospatial attention bias and motor laterality, with a left-visuospatial bias in the left-pawed group, a right-visuospatial bias in the right-pawed group and with the absence of significant visuospatial attention bias in ambi-pawed subjects. The current findings are the first evidence for the presence of a relationship between motor lateralization and visuospatial attentional mechanisms in a mammal species besides humans
Facial asymmetry in dogs with fear and aggressive behaviors towards humans
Full text linkThere is now scientific evidence that, in dogs, distinctive facial actions are produced in response to different emotionally-arousing stimuli suggesting a relationship between lateralized facial expressions and emotional states. Although in humans, relationships between facial asymmetry and both emotional and physiological distress have been reported, there are currently no data on the laterality of dogs’ facial expressions in response to social stimuli with respect to canine behavioral disorders. The aim of the present work was to investigate the facial asymmetries of dogs with fear and aggressive behavior towards humans during two different emotional situations: (1) while the dogs were alone in the presence of their owners and (2) during the approach of an unfamiliar human being. Overall, our results demonstrated high levels of asymmetries in facial expressions of dogs displaying fear and aggressive behaviors towards humans indicating that measuring facial asymmetries in dogs could prove to be a useful non-invasive tool for investigating physiology-based behavioral disorders
Lateralized Functions in the Dog Brain
Full text linkUnderstanding the complementary specialisation of the canine brain has been the subject of increasing scientific study over the last 10 years, chiefly due to the impact of cerebral lateralization on dog behaviour. In particular, behavioural asymmetries, which directly reflect different activation of the two sides of the dog brain, have been reported at different functional levels, including motor and sensory. The goal of this review is not only to provide a clear scenario of the experiments carried out over the last decade but also to highlight the relationships between dogs’ lateralization, cognitive style and behavioural reactivity, which represent crucial aspect relevant for canine welfare
Effect of Attentional Bias on the 3D Rotated Objects Recognition Ability of Dogs
No full textThe ability to recognize rotated objects has been widely reported in the animal kingdom. Studies on animal and human spatial cognition highlighted the importance of visuo-spatial cognitive capability for surviving in a dynamic world. Although domestic animals are frequently involved in activities requiring a high level of visuo-spatial ability, currently, little is known about their visuo-spatial skills. To investigate this issue, we trained six dogs to discriminate between 3D objects (using a modified version of the Shepard-Metzler task) that were then reproduced digitally on a computer. We found that the dogs recognized three-dimensional objects and their rotated versions (45° and 180°) more easily when presented on the left side of the screen, suggesting right hemisphere superiority in the control of visuo-spatial functions. Moreover, we report inter-individual variability in their performance in the visuo-spatial task. Our preliminary results suggest that dogs could use a rotational invariance process for the discrimination of 3D rotated shapes that deserves further investigation
Are dogs red–green colour blind?
Full text linkNeurobiological and molecular studies suggest a dichromatic colour vision in canine species, which appears to be similar to that of human red–green colour blindness. Here, we show that dogs exhibit a behavioural response similar to that of red–green blind human subjects when tested with a modified version of a test commonly used for the diagnosis of human deuteranopia (i.e. the Ishihara’s test). Besides contributing to increasing the knowledge about the perceptual ability of dogs, the present work describes for the first time, to our knowledge, a method that can be used to assess colour vision in the animal kingdom
Emotion Recognition in Cats
Full text linkRecent studies demonstrated that cats form social bonds with both conspecifics and humans. One of the key factors regulating social interactions is the transfer of emotions between the individuals. The present study aimed at investigating cats' spontaneous ability to match acoustic and visual signals for the recognition of both conspecific and human emotions. Different conspecific (cat "purr" and "hiss") and heterospecific (human "happiness" and "anger") emotional stimuli were presented to the tested population using a cross-modal paradigm. Results showed that cats are able to cross-modally match pictures of emotional faces with their related vocalizations, particularly for emotions of high intensity. Overall, our findings demonstrate that cats have a general mental representation of the emotions of their social partners, both conspecifics and humans
Relationship between motor laterality and aggressive behavior in sheepdogs
Full text linkSheepdogs' visuospatial abilities, their control of prey-driven behavior and their motor functions are essential characteristics for success in sheepdog trials. We investigated the influence of laterality on 15 sheepdogs' (Canis familiaris) spontaneous turning motor pattern around a herd and on their behavior during the first encounter with sheep in a training session. The most relevant finding of this research was that the dogs displayed significantly more aggressive behavior toward the sheep when turning in a counterclockwise direction around the herd. Considering that in counterclockwise turns the sheep were in the dogs' left visual hemifield, the high frequency of aggressions registered during counterclockwise turns suggests right hemisphere main activation. Overall, our results revealed the existence of a relationship between motor lateralization and aggressive behavior in dogs during sheepdog training and have practical implications for sheepdog training
Lateralized behavior and cardiac activity of dogs in response to human emotional vocalizations
Full text linkOver the recent years, the study of emotional functioning has become one of the central issues in dog cognition. Previous studies showed that dogs can recognize different emotions by looking at human faces and can correctly match the human emotional state with a vocalization having a negative emotional valence. However, to this day, little is known about how dogs perceive and process human non-verbal vocalizations having different emotional valence. The current research provides new insights into emotional functioning of the canine brain by studying dogs' lateralized auditory functions (to provide a first insight into the valence dimension) matched with both behavior and physiological measures of arousal (to study the arousal dimension) in response to playbacks related to the Ekman's six basic human emotions. Overall, our results indicate lateralized brain patterns for the processing of human emotional vocalizations, with the prevalent use of the right hemisphere in the analysis of vocalizations with a clear negative emotional valence (i.e. "fear" and "sadness") and the prevalent use of the left hemisphere in the analysis of positive vocalization ("happiness"). Furthermore, both cardiac activity and behavior response support the hypothesis that dogs are sensitive to emotional cues of human vocalizations
Correlations of Free Thyroid Hormones Measured by Tandem Mass Spectrometry and Immunoassay in Dogs
No full textThyroid function is commonly assessed in dogs through serum measurements of free thyroxine (FT4) and thyroid-stimulating hormone (TSH). The accurate measurement of thyroid hormones is critical. In particular, the measurement of free thyroxine (FT4) is important for the diagnosis and management of thyroid disorders. Most laboratories measure FT4 using direct analog immunoassay methods. The reliability of the results obtained using these methods has often been questioned. Fifty-nine dogs for which the veterinarian had requested the evaluation of thyroid hormones were included in this study. FT4 and TSH were measured using chemiluminescence enzyme immunoassay (CLEIA). Furthermore, FT4 was also measured by liquid chromatography–tandem mass spectrometry (LC-MS/MS) preceded by ultrafiltration. Comparing FT4 with the two different methods, the results demonstrate that LC-MS/MS, preceded by ultrafiltration, provides more accurate and specific FT4 measurements, particularly in dogs with altered thyroid hormone values. Although CLEIA is cost-effective and widely used for screening, LC-MS/MS is recommended for the more precise assessment of thyroid function
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