We tend to overestimate how gullible others are, but misinformation can have dramatic consequences, writes Dr Constance de Saint Laurent, Assistant Professor of Sociotechnical Systems at the Department of Psychology.

In October 1938, Orson Welles read part of his new novel – an adaptation of The War of Worlds by H. G. Wells – on US national radio. As the radio was still relatively new at the time, listeners took the story for reality.

Mass panic ensued, and the event went down in history as the first recorded instance of the mass media spreading misinformation. Or so the story goes. Ironically, the history of modern misinformation starts with a falsehood. Not only did few people tune in to the broadcast, most of those who did were well aware that it was a fiction.

But as inaccurate as this event is, it is quite symptomatic of our representation of misinformation. We tend to overestimate how gullible others are and to assume that they could believe widely inaccurate information, when they often don't.

Our tendency to overestimate the effects of inaccurate information has been studied since the 1980s under the name of 'third person effect'. The name refers to the fact that we often judge a generic third person as more gullible than ourselves or specific people we know. You might trust yourself and your friends not to believe that 5G chips are hidden in Covid vaccines, but you have more doubt about a random person on the street. This effect contributes to a lot of the hype around misinformation and what some researchers have called 'the echo chamber about echo chambers'.

Indeed, research on misinformation has shown that fake news is frequent online, but few people see it on a regular basis. And even fewer share it. A study of misinformation on Twitter during the 2016 US elections, for instance, has shown that 80% of the fake news displayed on the platform was seen by only 1% of users and that 0.1% of users were responsible for 80% of the fake news shared. In other words, a very small minority of people is overexposed to misinformation, while the rest of us have relatively good information diets.

Does that mean that we can all stop worrying about fake news and its effects? Sadly, not so much. Even if misinformation affects a small proportion of the population, it can have dramatic consequences. During the last US election, for instance, fake news convinced a portion of the US population that widespread election fraud made violence legitimate, resulting in the January 2021 insurrection.

In 2016, a conspiracy stating that Hillary Clinton was operating a paedophile ring from the basement of a pizzeria led to a man opening fire at the restaurant, which happened to not have a basement at all. Or, closer to home, misinformation spread on social media contributed to the radicalisation of many of the rioters in Dublin in November 2023, even if it was often spread from abroad.

Psychology has looked at what makes people more susceptible to believing in conspiracies, as radical misinformation tends to be in the form of conspiracy theories. Certain personality traits correlate with a conspiracy mindset, such as paranoia or pessimism. World views also matter, with conservatives often more likely to fall for misinformation, although the left is far from immune.

But as these communities grow, the question of how to effectively deradicalise misinformation believers becomes more pressing, and still does not have an answer. This is because misinformation bubbles create a sort of alternative reality for part of the population, where nothing the state, media nor experts say can have any weight. Once people fall down the 'rabbit hole' of conspiracy theories and fake news, they can be impossible to reach. After all, whatever you say only shows that you are part of the ‘system’.

What conspiracy believers believe in, first and foremost, is that the truth is hidden by powerful actors. This makes them more likely to subscribe to unrelated theories. Believing that climate change is a hoax makes you more likely to believe the moon landing was fake. What unites both theories is the conviction that there is something fishy about the official stories. This makes rebuttals nearly impossible: Each disproven theory can be instantly replaced by a new one.

If misinformation mainly affects a small part of the population, does it mean that the rest of us are immune? Not so much. While most of us do not believe in fake news, it does not mean it does not have an effect. This is because being aware that misinformation circulates online does not just make you more careful with inaccurate information: It makes you generally more sceptical. In other words, fake news makes us more likely to distrust real news. This makes campaigns to raise awareness on the risk of false news quite tricky, as they always risk increasing scepticism.

During the pandemic, people who rejected the vaccines did not necessarily believe that it was used to euthanise part of the population or to inject mind controlling chips, as some of the theories went. Instead, many just didn't trust the official information telling them it was safe. This has been one of the most important and dangerous effects of the misinformation epidemic: it has lowered people’s trust in expertise and quality media, a key factor in vaccine hesitancy.

At a time when repeated crises – be they political, economic, environmental – make evidence-based action all the more necessary, the knowledge industry is facing an unprecedented crisis. Remember too that this was before ChatGPT entered the game. Generative AI is able to produce vast amounts of misinformation, even when it is trying to be accurate. It is now more important than ever to find effective solutions to misinformation - and that is solutions rooted in facts, and not in our misconceptions of misinformation.

This piece originally appeared on RTÉ Brainstorm