Bots increase exposure to negative and inflammatory content in online social systems
Open accessAbstract
Significance: Social media can deeply influence reality perception, affecting millions of people’s voting behavior. Hence, maneuvering opinion dynamics by disseminating forged content over online ecosystems is an effective pathway for social hacking. We propose a framework for discovering such a potentially dangerous behavior promoted by automatic users, also called “bots,” in online social networks. We provide evidence that social bots target mainly human influencers but generate semantic content depending on the polarized stance of their targets. During the 2017 Catalan referendum, used as a case study, social bots generated and promoted violent content aimed at Independentists, ultimately exacerbating social conflict online. Our results open challenges for detecting and controlling the influence of such content on society.
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The 12-second timing gap constitutes direct evidence of coordinated manipulation analogous to bot farming on human social media platforms.
“The 12-second timing gap constitutes direct evidence of coordinated manipulation analogous to bot farming operations documented on human social media platforms 13,16,22 .”
From The Moltbook Illusion: Separating Human Influence from Emergent Behavior in AI Agent Societies (2026) · cites this paper as [22]
The Discussion (page unavailable) describes bots targeting human influencers and manipulating information exposure on Twitter, supporting the broad analogy to social-media bot manipulation. The Results (page unavailable) discuss activity over time but do not report a 12-second gap or establish that such a gap is direct evidence of coordination; the paper also does not identify its activity as bot farming. (LLM, conf=0.84)
Experimental — accuracy not yet measuredScholars still lack a widespread consensus on the impact of social bots.
“In fact, scholars still lack a widespread consensus on the impact of social bots, with some studies reporting on their pivotal role for increasing disinformation's spread, polarization, and hateful speech [27, 29], and competing results claiming that bots do not play a significant role in these processes [32].”
From A decade of social bot detection (2020) · cites this paper as [29]
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- Authors
- Stella, M., Ferrara, E., & De Domenico, M.
- Affiliations
- Fondazione Bruno Kessler (IT)
- University of Southern California (US)
- Center for Information and Communication Technology, Fondazione Bruno Kessler, 38123 Trento, Italy;
- Corresponding author
- Ferrara, Emilio
- Venue
- Proceedings of the National Academy of Sciences
- Publisher
- National Academy of Sciences
- Published
- 2018-11-20
- Volume
- 115
- Issue
- 49
- Pages
- 12435-12440
- ISSN
- 0027-8424 (ISSN-L)
- 1091-6490
- PMC
- PMC6298098
- OpenAlex
- W2900936184
- Cited by
- 492
- References
- 41
- Citations by year
- 2026: 40 · 2025: 50 · 2024: 44 · 2023: 53 · 2022: 73 · 2021: 70 · 2020: 121 · 2019: 38 · 2018: 1 · 2017: 2
- FWCI
- 130.65
- Type
- journal article
- Language
- en
- Open access
- hybrid
- doi.org
- Licence
- Locations
- Proceedings of the National Academy of Sciences (publishedVersion, cc-by-nc-nd)
- Europe PMC (PubMed Central) (publishedVersion, cc-by-nc-nd)
- PubMed Central (publishedVersion, cc-by-nc-nd)
- PubMed (publishedVersion)
- arXiv (Cornell University) (submittedVersion)
- SSRN Electronic Journal (submittedVersion)
- RePEc: Research Papers in Economics (submittedVersion)
- Iris (University of Trento) (submittedVersion, cc-by-nc-nd)
- Padua Research Archive (University of Padova) (submittedVersion)
- arXiv (Cornell University)
- Funders
- DOD | USAF | AFMC | Air Force Office of Scientific Research (FA9550-17-1-0327)
- Topics
- Social Sciences › Sociology and Political Science › Misinformation and Its Impacts
- Social Sciences › Communication › Social Media and Politics
- Physical Sciences › Computer Science › Information Systems › Spam and Phishing Detection
- Keywords
- social bots, online polarization, Catalan independence referendum, Twitter, political conflict, bot detection
- MeSH terms
- Aggression, Humans, Politics, Spain, Expressed Emotion, Internet, Social Networking, Social Media
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