High pitch sounds small for domestic dogs dataset

Humans possess intuitive associations linking certain non-redundant features of stimuli – e.g., high-pitched sounds with small object-size (or similarly, low-pitched sounds with large object-size). This phenomenon, known as crossmodal correspondence, has been identified in humans across multiple different senses. There is some evidence that non-human animals also form crossmodal correspondences, but the known examples are mostly limited to the associations between the pitch of vocalisations and the size of callers. To investigate whether domestic dogs, like humans, show abstract pitch-size association, we first trained dogs to approach and touch an object after hearing a sound emanating from it. Subsequently, we repeated the task but presented dogs with two objects differing in size, only one of which was playing a sound. The sound was either high- or low-pitched, thereby creating trials that were either congruent (high-pitch from small object; low-pitch from large objects) or incongruent (the reverse). We found that dogs reacted faster on congruent versus incongruent trials. Moreover, their accuracy was at chance on incongruent trials, but significantly above chance for congruent trials. Our results suggest that non-human animals show abstract pitch-sound correspondences, indicating these correspondences may not be uniquely human but rather a sensory processing feature shared by other species.

人类天生具备将刺激物的若干非冗余特征进行直觉性联结的能力，例如将高音调声音与小物体尺寸相关联（反之，低音调声音与大物体尺寸相关联）。这一现象被称为跨模态对应（crossmodal correspondence），已在人类的多种不同感官通道中被证实存在。现有部分证据表明，非人类动物同样会形成跨模态对应，但目前已知的案例大多局限于发声音高与发声者体型之间的关联。为探究家犬是否与人类一样具备抽象的音高-体型联结能力，我们首先训练家犬在听到某物体发出的声音后，靠近并触碰该物体。随后，我们重复该任务，但向家犬呈现两个尺寸不同的物体，且仅其中一个物体会播放声音。实验中所播放的声音分为高音调与低音调两类，由此形成两类试次：一致试次（小物体发出高音调声音、大物体发出低音调声音）与不一致试次（反之）。结果发现，家犬在一致试次中的反应速度快于不一致试次。此外，家犬在不一致试次中的准确率处于随机水平，而在一致试次中的准确率则显著高于随机水平。本研究结果表明，非人类动物同样具备抽象的音高-体型跨模态对应能力，这意味着跨模态对应并非人类独有的特性，而是其他物种也共有的一种感官加工特征。