In everyday digital life, millions of people participate in online communities to share interests, seek belonging, and connect with others. Especially during adolescence and young adulthood, platforms centered around gaming, fandom, or technology can offer important spaces for identity formation and social support. Yet these same environments can also foster toxic dynamics, normalization of harmful ideologies, and gradual radicalization—often without clear boundaries between ”mainstream” interaction and extremist discourse. But why do some online communities become hostile, exclusionary, and radicalized over time? How do seemingly harmless digital spaces turn into environments shaped by hate, misogyny, or extremist worldviews? And why do these processes often remain unnoticed until they reach a critical point?

This seminar examines the social processes through which online communities degrade into toxic spaces. Besides focusing on individual perpetrator profiles and specific cases of extremism, the course takes a community-centered perspective. We explore how group dynamics, platform affordances, communicative escalation, and strategic manipulation interact to produce self-reinforcing spirals of exclusion, hostility, and ideological hardening. We will analyze examples of online subcultures such as gamer cultures, the manosphere and other toxic and hate dominated communities to understand how radicalization can emerge as an everyday, gradual process. Key questions include: How does toxicity become normalized? What role do influencers, ”dark agents,” or highly active community members play? How do platform logics and algorithms shape visibility, attention, and conflict? And why are these developments so difficult to detect from the outside?

Drawing on research from communication studies, sociology and psychology, the seminar introduces central concepts such as online radicalization, toxic masculinity, group polarization, dark participation, and digital manipulation. We will also discuss a range of methodological approaches—both qualitative and quantitative—that researchers use to study these phenomena. Finally, the seminar turns to the question of intervention and prevention. What can be done to counter toxic dynamics before they escalate? How can communities, platforms, and societies foster safer online environments without suppressing legitimate dissent or subcultural expression? And what responsibilities do researchers and practitioners have when studying and engaging with harmful online spaces?

Coursework: active participation, preparation and moderation of a thematic unit
Examination/Assessment: term paper

Kurs im HIS-LSF