Sander van der Linden

Health and biosecurity preparedness focuses on pathogen detection, laboratory security and countermeasure development, yet these capabilities depend on information environments that can be manipulated. Adversaries can undermine a biological response without ever touching a pathogen: distorting how health information is produced, authenticated or circulated can reduce reporting and countermeasure uptake, endanger health workers and disrupt coordination. In this Health Policy paper, we describe a four stage pathway through which scientific uncertainty, social memory, data voids and borrowed authority are turned into operational harm, and show that generative AI accelerates each stage. We argue that digital surveillance should track loss of response function rather than volume of misleading content. Because evidence is split across health agencies, platforms, AI providers and publishers, we propose a two stage threshold: corroborated manipulation with credible effects on the response opens a time limited assessment and evidence preservation, whereas coercive measures require evidence of intent and independent authorisation.

Political polarization poses major societal risks, yet a globally relevant, interdisciplinary understanding remains lacking, as nearly half of all studies focus on the United States. We argue for renewed effort to bring global equity to polarization research, highlighting insights robust across countries, those unique to specific contexts, and key literature gaps. Closing these gaps means overcoming cultural and systemic barriers, including data-access restrictions and misaligned incentives. It also demands interdisciplinarity bridging traditional approaches and those addressing the polarizing role of the internet, social media, and AI. Otherwise, efforts to counter polarization, and its democratic harms, risk resting on unsuitable evidence.

Individuals encounter “climate doom,” extreme portrayals of climate change, on social media. While climate doom may be intended to motivate action, it may also be perceived as manipulative or elicit hopelessness. Yet, no research has examined whether psychological inoculation helps to improve recognition of climate doom or influences engagement with it on social media. In this preregistered study ( n = 521), we tested whether inoculation improves discernment of climate doom and influences engagement with it by collecting behavioral data using a social media simulator. We find that inoculation substantially improves discernment of climate doom and that this is due to increased perceived manipulation of doom messaging specifically ( d = 0.68). There was no interaction between the inoculation condition and political leaning and while higher perceived manipulation of doom content predicted lower behavioral intentions, inoculation did not moderate this relationship. Inoculation increased engagement, particularly disliking and flagging of doom content, and decreased sharing. Overall, our results should lead climate communicators to reconsider doom messaging as a mobilization strategy and demonstrate that inoculation is an effective tool for increasing recognition of, and critical engagement with, climate doom across the political spectrum.

There is widespread concern that misinformation poses dangerous risks to health, well-being, and civic life. Despite a growing body of research on the topic, significant questions remain about the psychological factors that render people susceptible to misinformation, the extent to which it affects real-world behavior, how it spreads online and offline, and intervention strategies that counter and correct misinformation effectively. This report reviews the best available psychological science research to reach consensus on each of these crucial questions, particularly as they pertain to health-related misinformation. In addition, the report offers eight specific recommendations for scientists, policymakers, and health professionals who seek to recognize and respond to misinformation in healthcare and beyond. (PsycInfo Database Record (c) 2025 APA, all rights reserved).

Inoculation is serious business, but that does not mean it cannot be viewed through a perspective of humor, nor that humor cannot be part of the process of attitude resistance. This applies to both medical and communication-based inoculation, with scientists examining how humor could function as an adjuvant and facilitate resistance to persuasive attacks. Though relatively limited, considerations of humor have been part of inoculation theory from the beginning—dating back from McGuire’s seminal 1964 review to the prominent role of humor in modern gamified inoculation interventions against misinformation. In this article, we explore humor’s role in inoculation theory, review emerging research, and propose promising directions for future theory and application.

Short video-based prebunking reduces misinformation susceptibility by forewarning viewers about manipulation tactics. However, its effectiveness across older populations (45 + ), diverse cultures, and election-related misinformation remains unclear. To address this, we conducted 13 surveys across 12 EU nations ( N = 19,735), testing three inoculation videos developed for the largest prebunking campaign to date, which reached 120M+ YouTube users before the 2024 EU Elections. These videos targeted three widely used misinformation tactics—scapegoating, decontextualization, and discrediting—which were prevalent across EU nations leading up to the elections. The videos improved manipulation (measured through manipulativeness assessments) and technique (measured through the correct identification of tactics) discernment of manipulative content from non-manipulative content and enhanced sharing decisions. Though effects were small ( d s ≈ 0.08–0.38), they were significant across surveys. Longer (50 s ) videos showed more consistent improvements in discernment than shorter (20 s ) ones, but both improved technique discernment. Moderation analyses revealed country-level (e.g., education index) and socio-demographic (e.g., personal educational attainment) influences that could inform future interventions. These findings demonstrate that scalable video-based inoculation interventions can be deployed to counter election misinformation across nations, but future work should explore how repeated or context-specific prebunking can sustain resistance to misinformation in diverse electoral and media environments.