Evaluating real-world effects of one-off fake news exposure

While misinformation is often assumed to directly affect behaviour, experimental tests of this hypothesis are rare. We examined effects of a single exposure to misinformation on political and non-political behaviours. Study 1 participants (N = 2,397) were exposed to a fabricated news story about food contamination, with a subset (n = 143) subsequently invited to taste the targeted foods in a laboratory setting. Exposure to the fabricated story did not significantly affect attitudes towards or consumption of the target food. Study 2 (n = 417) confirmed that results were not specific to the particular story presented. Finally, Study 3 (n = 413) tested effects of misinformation about climate change. Exposure to climate-skeptical misinformation reduced signatures on an online petition, but had no effect on two other targeted behaviours. We conclude with a call for further experimental research to delineate the conditions under which misinformation does and does not affect behaviour.