Data from: Dogs recognize dog and human emotions

The perception of emotional expressions allows animals to evaluate the social intentions and motivations of each other. This usually takes place within species; however, in the case of domestic dogs, it might be advantageous to recognize the emotions of humans as well as other dogs. In this sense, the combination of visual and auditory cues to categorize others' emotions facilitates the information processing and indicates high-level cognitive representations. Using a cross-modal preferential looking paradigm, we presented dogs with either human or dog faces with different emotional valences (happy/playful versus angry/aggressive) paired with a single vocalization from the same individual with either a positive or negative valence or Brownian noise. Dogs looked significantly longer at the face whose expression was congruent to the valence of vocalization, for both conspecifics and heterospecifics, an ability previously known only in humans. These results demonstrate that dogs can extract and integrate bimodal sensory emotional information, and discriminate between positive and negative emotions from both humans and dogs.

对情绪表情的感知，使得动物能够评估同类间的社交意图与动机。这一过程通常发生在同一物种内部；但对于家养犬而言，同时识别人类与其他同类的情绪或许更具进化优势。从这一角度而言，结合视觉与听觉线索对他者情绪进行分类，能够优化信息处理流程，并体现出高级认知表征能力。本研究采用跨模态优先注视范式（cross-modal preferential looking paradigm），向受试家犬展示带有不同情绪效价（emotional valences）的人类或犬类面部表情（愉快/嬉戏 vs 愤怒/攻击性），并搭配同一发声个体发出的正性、负性发声信号或布朗噪声（Brownian noise）。无论面对同种个体（conspecifics）还是异种个体（heterospecifics）的面部刺激，家犬都会显著更长时间地注视与发声效价一致的表情——此前这种能力仅在人类中被发现。上述实验结果证明，家犬能够提取并整合双模态感官情绪信息，同时可以区分人类与同类的正性与负性情绪。