# Behavioural Analysis of Dogs' Response to Threatening and Neutral Conspecific Video Stimuli +
However, it is very difficult to standardise the behaviour of an \"actor/stooge\" dog approaching different unfamiliar dogs in such a way as to ensure the final approach will be either threatening or neutral. Thus, exposing dogs to moving visual representations (videos) of conspecifics could allow standardised conspecific stimuli to be used in order to study dogs' intraspecific visual communication. The use of videos depicting different conspecific communication signals has already been adopted in studies with other species with promising results: juvenile bonnet macaques (_Macaca radiata_) behave in a socially appropriate manner, acting in a submissive way and seeking contact with mates when viewing videos of threatening males while approaching videos of a passive female [22]. Furthermore, they are more attentive to videos of conspecificics scratching compared to performing a neutral behaviour suggesting a signalling function of the behaviour [23]. Several studies have looked at aspects of dogs' visual and social cognition using experimental paradigms involving the broadcasting of images or videos. Dogs are skilful at discriminating pictures of conspecifics from human or other animal faces [24; 25] and can match different dog vocalizations to coherent pictorial representations [26; 27; 28]. Video stimuli have been successfully used in domestic dog cognition research, for example, showing that dogs performed at above chance level in a classic pointing task when a projection of an experimenter performing the pointing gestures was used, thus implying that dogs could perceive the actual content of the videos as a human being [29]. Evidence suggests that dogs process the videos in a \"confusion mode\", exchanging the image and its referent and thus reacting roughly the same way to an image as to the real object [30]. Finally, in an expectancy violation paradigm in which dogs were presented with videos of conspecifics and heterospecifics paired with coherent and incoherent auditory stimuli, dogs seemed to recognise (looking more at the non-matching stimuli) the visual (video) and auditory stimuli as belonging to a conspecific compared to another species [31]. Given the evidence for dogs being sensitive to video stimuli of conspecifics and possibly responding in a socially appropriate manner, the current study had two objectives. The primary aim was to investigate whether displacement behaviours may carry an \"appeasing\" function. Thus, the use of naturalistic videos, including their auditory stimuli was adopted to expose dogs to a standardised conflict-ridden (threatening dog) and non-conflict-ridden (neutral dog) situation and measure the occurrence of displacement behaviours and facial expressions under the two conditions. Although in our previous study with human strangers [20], dogs were not observed to exhibit these behaviours more frequently in a threatening compared to a neutral condition, given the few studies carried out with conspecifics, the predictions for this study were based on the \"appeasement signal hypothesis\". Hence, it was predicted that dogs would exhibit displacement behaviours more frequently when exposed to videos of conspecifics showing threatening compared to neutral behaviour. Previous results have shown that dogs' behavioural reactions can be elicited solely by socially relevant conspecific auditory cues [27]; however, it is not clear to what extent visual cues may be sufficient. Thus, the secondary aim of this study was to assess whether the visual component of the stimuli would elicit the appropriate responses in dogs, thereby providing a tool for future studies. Thus, we included a condition in which the same videos were presented but paired with artificial non-species-relevant auditory cues (i.e., pink noise).