Background Empathy refers to the ability to recognise and share emotions with others. Several research groups have recognised observational fear in mice as a useful behavioural model for assessing their ability to empathise. However, in these observation systems, it remains unclear whether the observer mouse truly recognises the movements of, and empathises with, the demonstrator mouse. We examined changes in the behaviour of an observer mouse when a demonstrator mouse was anaesthetised, when the demonstrator’s activity was increased, and when the interval of electrical stimulation was altered. If mice exhibit an ability to empathise, then the observer should display empathic behaviour when the demonstrator experiences pain or discomfort under any circumstances. Results Relative to low-frequency stimulation, frequent electrical stimulation reduced immobility time among observer mice. Moreover, when demonstrators exhibited excessive activity, the activity of the observers significantly increased. In addition, the proportion of immobility time among observer mice significantly increased when demonstrator mice exhibited fear learning and excessive immobility. Conclusion Although our results indicate that observer mice change their behaviour based on the movements of demonstrator mice, increases in immobility time may reflect conformity-like behaviour rather than emotional empathy. Thus, not only visual but also auditory and odour information additionally influenced the conformity-like behaviour shown by observer mice. Thus, our findings suggest that methods other than the fear observation system should be used to investigate rodent empathy-like behaviour.

中文翻译：

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观察其他小鼠冻结的小鼠的一致性行为：同理心模型

背景同理心是指识别并与他人分享情绪的能力。几个研究小组已经认识到小鼠的观察性恐惧是评估其同理心能力的有用行为模型。然而，在这些观察系统中，尚不清楚观察者鼠标是否真正识别演示者鼠标的动作并与之产生共鸣。我们检查了当演示小鼠被麻醉、演示者的活动增加以及电刺激间隔改变时观察者小鼠行为的变化。如果老鼠表现出移情能力，那么当示范者在任何情况下感到疼痛或不适时，观察者都应该表现出移情行为。结果相对于低频刺激，频繁的电刺激减少了观察小鼠的不动时间。此外，当示威者表现出过度活跃时，观察者的活跃度显着增加。此外，当示范小鼠表现出恐惧学习和过度不动时，观察者小鼠的不动时间比例显着增加。结论 虽然我们的结果表明观察者老鼠会根据示范老鼠的运动改变他们的行为，但不动时间的增加可能反映了类似从众的行为，而不是情感上的同理心。因此，不仅视觉而且听觉和气味信息也会影响观察小鼠表现出的类似从众行为。因此，