Vocal learning species such as humans and parrots show auditory dominance when they synchronize their actions to an external rhythm. However, whether non-vocal-learners show a specific modality dominance in a rhythmic task has scarcely been examined. We predicted that rats, who are nocturnal and known to rely on acoustic communication, would exhibit higher sensitivity to auditory rhythm compared to visual rhythm. We investigated whether performance of a synchronization task by rats differs based on stimulus modality. We trained five rats to press a lever in time to auditory-visual, isochronous stimuli presented at three different tempos. Rats showed a lower correct response rate when auditory stimuli were presented than when visual or auditory-visual stimuli were presented in the 0.5-s inter-onset interval condition. Neither the asynchrony with the stimulus onset, nor the variability of interval production differed significantly based on the stimulus modality. Therefore, contrary to the prediction, they did not show auditory dominance; rather, rats showed poor performance on the task when a visual stimulus was not present. These results are consistent with the gradual audio-motor evolution hypothesis, and suggest that rats share ability for rhythm production, but this might not necessarily depend on auditory modality.

当人类和鹦鹉等声乐学习物种将自己的动作与外部节奏同步时，它们会表现出听觉优势。然而，几乎没有研究过非声乐学习者是否在有节奏的任务中表现出特定的模态优势。我们预测，与视觉节律相比，夜间活动且已知依赖声学交流的老鼠对听觉节律表现出更高的敏感性。我们调查了大鼠同步任务的表现是否因刺激方式而异。我们训练五只老鼠及时按下杠杆，以适应以三种不同节奏呈现的听觉-视觉、同步刺激。当呈现听觉刺激时，大鼠的正确反应率低于在 0.5 秒间隔条件下呈现视觉或听觉-视觉刺激时的正确反应率。与刺激开始的不同步性和间隔产生的可变性都没有根据刺激方式而显着不同。因此，与预测相反，它们没有表现出听觉优势；相反，当没有视觉刺激时，老鼠在任务中表现不佳。这些结果与逐渐的音频运动进化假设一致，并表明大鼠共享节奏产生的能力，但这可能不一定取决于听觉模式。