Affect-sharing, the ability to vicariously feel another person's emotions, is the primary component of empathy that is typically thought to rely on the observer's capacity to feel the emotions of others. However, external signals, such as the target's physical characteristics, have been demonstrated to influence affect-sharing in the neuroscientific literature that speaks to the underappreciated role of external factors in eliciting affect-sharing. We consider factors that influence affect-sharing, including physical cues, emotional cues, situational factors, and observer-target relationships, as well as the neural circuits involved in these processes. Our review reveals that, while neural network activation is primarily responsible for processing affect-sharing, external factors also co-activate a top-down cognitive processing network to modulate the conscious process of affect-sharing. From this knowledge, an integrative framework of external factor interactions with affect-sharing are explained in detail. Finally, we identify critical areas for future research in social and affective neuroscience, including research gaps and incorporation of ecologically valid paradigms.

情感分享，即间接感受他人情绪的能力，是同理心的主要组成部分，通常被认为依赖于观察者感受他人情绪的能力。然而，神经科学文献已证明外部信号（例如目标的身体特征）会影响情感共享，这表明外部因素在引发情感共享方面的作用未被充分认识。我们考虑影响情感分享的因素，包括身体暗示、情绪暗示、情境因素和观察者-目标关系，以及这些过程中涉及的神经回路。我们的评论表明，虽然神经网络激活主要负责处理情感共享，但外部因素也共同激活自上而下的认知处理网络来调节情感共享的意识过程。根据这些知识，详细解释了外部因素相互作用与情感共享的综合框架。最后，我们确定了社会和情感神经科学未来研究的关键领域，包括研究差距和生态有效范式的纳入。