微观人际价值视角下的行为免疫双边互动
Micro-level Interpersonal Motives and the Dual Dynamics of Behavioral Immunity
独秀创新讲坛 Duxiu Innovation Talk Series
经典理论认为，行为免疫系统（BIS）是一套引导接触与社交决策的心理机制，用以降低感染风险。但现实研究对其中一些核心假设提出了挑战，尤其是在群际层面。基于新冠疫情期间的两项纵向追踪和一项跨文化注册研究，我们发现：无论是环境中可感知的疾病威胁，还是外群体线索，这些传统上被视为关键的因素，并未稳定地引发回避或排外。相反，真正的调节机制来自微观的人际价值。人们更愿意为亲密或高价值对象承担风险，而更倾向于回避低价值或不可信对象。纵向数据同样表明，人们对“共享微生物式”风险接触（如近距离、共用品）的舒适度，更取决于对方是谁，而非疫情曲线。重要的是，这种调节不仅存在于健康个体，感染者的行为也会进行镜像的调整：面对高价值关系对象，他们更少隐瞒，甚至更可能主动披露病情。总体而言，感染风险的调控是关系性的、动态的，由避免感染、防止被利用、减少排斥和寻求照料等多种社会动机共同塑造。传染因此是一个双边互动过程：健康个体主要调节回避，感染个体主要调节隐瞒或披露，双方以不同方式权衡社会价值决定行为。这个双主体视角将 BIS 从单纯的病原反应机制重塑为嵌入社会关系的动机系统，并提示需要与生理免疫（PIS）相结合。我们的后续研究以肠–脑通路为切入口，探讨生物状态与社会动机如何共同塑造与疾病相关的行为与互动。
Classic accounts characterize the behavioral immune system (BIS) as a set of psychological processes guiding contact and social decisions to reduce behavioral exposure to pathogens, yet real-world evidence challenges several of its core predictions. Across longitudinal studies during the COVID-19 pandemic and a cross-cultural registered report, we found little evidence that ecological disease salience or ethnic outgroup cues—two factors often cited as important influences—reliably increased avoidance or xenophobia. This raises a broader question: if abstract macro-level cues are insufficient, what actually regulates disease-related behavior? Our work suggests that the answer lies in micro-level interpersonal motives. People are more willing to risk infection with close or valued partners, and less willing with untrustworthy or low-value ones. Longitudinal data likewise show that people’s evaluations of their interaction partners, and their comfort with microbe-sharing contact, depend more on partner identity than on epidemic curves. Crucially, this tuning is not limited to healthy perceivers. Infected individuals also adjust: with high-value partners, they conceal illness less and sometimes even disclose it more. Together, these findings reveal that pathogen regulation is inherently relational and dynamic, shaped by motives such as avoiding infection, preventing exploitation, reducing social exclusion, and seeking care. Importantly, they highlight that contagion is a two-sided interaction: healthy individuals regulate avoidance, while infected individuals regulate disclosure, each negotiating social value in different ways. This dual perspective not only reframes behavioral immunity as a socially embedded motivational system, but also points toward the need to integrate BIS with physiological immunity (PIS). Our future work takes this step by examining gut–brain pathways as one entry point into how biological states and social motives jointly shape disease behavior and interaction.