Conspiracy theories present significant societal challenges, shaping political behavior, eroding public trust, and disrupting social cohesion. Addressing their impact requires recognizing that conspiracy engagement is not a singular act but a multi-stage process involving distinct cognitive and behavioral transitions. In this study, we investigate this sequential progression, "recognition," "belief," and "action" (demonstrative action and diffusion action), using nationally representative surveys from the United States (N=13,578) and Japan (N=16,693). Applying a Bayesian hierarchical model, we identify the key social, political, and economic factors that drive engagement at each stage, providing a structured framework for understanding the mechanisms underlying conspiracy theory adoption and dissemination. We find that recognition serves as a crucial gateway determining who transitions to belief, and that demonstrative and diffusion actions are shaped by distinct factors. Demonstrative actions are more prevalent among younger, higher-status individuals with strong political alignments, whereas diffusion actions occur across broader demographics, particularly among those engaged with diverse media channels. Our findings further reveal that early-life economic and cultural capital significantly influence the shape of conspiratorial engagement, emphasizing the role of life-course experiences. These insights highlight the necessity of distinguishing between different forms of conspiracy engagement and highlight the importance of targeted interventions that account for structural, cultural, and psychological factors to mitigate their spread and societal impact.

翻译：阴谋论构成了重大的社会挑战，它们塑造政治行为、侵蚀公众信任并破坏社会凝聚力。要应对其影响，需要认识到参与阴谋论并非单一行为，而是涉及不同认知与行为转变的多阶段过程。本研究利用美国（N=13,578）和日本（N=16,693）的全国代表性调查数据，考察了"认知"、"相信"与"行动"（展示性行动与扩散性行动）这一序列进程。通过应用贝叶斯分层模型，我们识别了驱动各阶段参与的关键社会、政治与经济因素，为理解阴谋论采纳与传播的内在机制提供了结构化框架。研究发现，认知是决定个体是否转向相信的关键门户；展示性行动与扩散性行动受不同因素影响。展示性行动在具有强烈政治倾向、地位较高的年轻群体中更为普遍，而扩散性行动则跨越更广泛的人口群体，尤其在接触多元媒体渠道的个体中更为常见。我们的研究进一步揭示，早年经济与文化资本显著影响阴谋论参与形态，凸显了生命历程经历的重要作用。这些发现强调有必要区分不同形式的阴谋论参与，并指出需结合结构性、文化性与心理性因素制定针对性干预措施，以减轻其传播与社会影响。