Fake news stories are more likely to be believed and consequently shared on social media if readers think they have seen them before, research suggests.
Academics at Cardiff University's Crime and Security Research Institute say their report offers insights into the reasons why seemingly outlandish claims on social media can gain traction.
The team devised a fake news story and showed it to 8,630 citizens from 12 different European countries before assessing their reactions. The fabricated story, about a communist killer dolphin heading to a popular holiday resort, was intentionally similar to previous media reports about the use of dolphins and whales for government-led espionage activities.
More than half (53%) of those who thought they recognised the news story believed the content to some degree, compared to 10% of those who did not recognise the story.
Those who recognised the story and those who believed the story experienced the strongest emotional response to the content. In all countries, the data showed a significant link between emotion and behavioural engagement – such as clicking on the link or sharing the story with others.
Professor Kate Daunt, of the Open Source Communications, Analytics Research (OSCAR) Programme, said: "Testing citizens' responses to fake news by showing them the same invented story has allowed us draw meaningful conclusions about the spread of disinformation. Our results highlight the importance of the 'illusory truth effect', whereby individuals are more likely to believe a message encountered repeatedly over time. Although the story seemed implausible to most, a large proportion of those questioned believed the story to differing extents in part because they felt they had seen it before.
