TikTok as algorithmically mediated biographical illumination: Autism, self-discovery, and platformed diagnosis on #autisktok

Scholarship in the sociology of medicine has tended to characterize diagnosis as disruptive to one's self-concept. This categorization, though, requires reconsideration in light of public conversations about mental health and community building around neurocognitive conditions, particularly among youth online. Drawing upon Tan's notion of "biographical illumination" (BI), which describes how medical frameworks can enrich personal biographies, we explored the shifting nature of BI through the case of TikTok. Combining quantitative and qualitative methods, we argue that TikTok serves as a space to discuss diagnosis and refine one's sense of self as a result of diagnosis. However, such personal transformation is inseparable from the app's affordances, or what we term "algorithmically mediated biographical illumination." BI shapes TikTok as a platform, and TikTok informs BI as a psychosocial process, leading to what we call "platformed diagnosis." These findings have broader critical applications for the study of algorithms, disability, and digital platforms.