Visual content on social media has become increasingly influential in shaping political discourse and civic engagement. Using a dataset of 239,526 Instagram images, deep learning, and LLM-based workflows, we examine the impact of different content types on user engagement during the 2024 US presidential Elections, with a focus on synthetic visuals. Results show while synthetic content may not increase engagement alone, it mediates how political information is created through highly effective, often absurd, political memes. We define the notion of generative memesis, where memes are no longer shared person-to-person but mediated by AI through customized, generated images. We also find partisan divergences: Democrats use AI for in-group support whereas Republicans use it for out-group attacks. Non-traditional, left-leaning outlets are the primary creators of political memes; emphasis on different topics largely follows issue ownership.

翻译：社交媒体上的视觉内容对政治话语与公民参与的影响日益显著。本研究基于239,526张Instagram图像数据集，结合深度学习与基于大语言模型的工作流程，考察了2024年美国总统选举期间不同类型内容对用户参与度的影响，重点关注合成视觉内容。研究结果表明：虽然合成内容本身未必提升参与度，但其通过高效且常具荒诞性的政治迷因，中介了政治信息的生成过程。我们提出"生成式模因传播"概念——迷因不再仅通过人际传播，而是经由AI通过定制化生成图像实现中介传播。研究同时发现党派差异：民主党倾向使用AI进行群体内支持，共和党则更多用于群体外攻击。非传统左倾媒体是政治迷因的主要生产者；对不同议题的侧重基本遵循议题所有权理论。