Why Your Brain Falls for Misinformation – And How to Avoid It
This article is part of the magazine, "The Future of Science In America: The Election Issue," co-published by LeapsMag, the Aspen Institute Science & Society Program, and GOOD.
Whenever you hear something repeated, it feels more true. In other words, repetition makes any statement seem more accurate. So anything you hear again will resonate more each time it's said.
Do you see what I did there? Each of the three sentences above conveyed the same message. Yet each time you read the next sentence, it felt more and more true. Cognitive neuroscientists and behavioral economists like myself call this the "illusory truth effect."
Go back and recall your experience reading the first sentence. It probably felt strange and disconcerting, perhaps with a note of resistance, as in "I don't believe things more if they're repeated!"
Reading the second sentence did not inspire such a strong reaction. Your reaction to the third sentence was tame by comparison.
Why? Because of a phenomenon called "cognitive fluency," meaning how easily we process information. Much of our vulnerability to deception in all areas of life—including to fake news and misinformation—revolves around cognitive fluency in one way or another. And unfortunately, such misinformation can swing major elections.
The Lazy Brain
Our brains are lazy. The more effort it takes to process information, the more uncomfortable we feel about it and the more we dislike and distrust it.
By contrast, the more we like certain data and are comfortable with it, the more we feel that it's accurate. This intuitive feeling in our gut is what we use to judge what's true and false.
Yet no matter how often you heard that you should trust your gut and follow your intuition, that advice is wrong. You should not trust your gut when evaluating information where you don't have expert-level knowledge, at least when you don't want to screw up. Structured information gathering and decision-making processes help us avoid the numerous errors we make when we follow our intuition. And even experts can make serious errors when they don't rely on such decision aids.
These mistakes happen due to mental errors that scholars call "cognitive biases." The illusory truth effect is one of these mental blindspots; there are over 100 altogether. These mental blindspots impact all areas of our life, from health and politics to relationships and even shopping.
We pay the most attention to whatever we find most emotionally salient in our environment, as that's the information easiest for us to process.
The Maladapted Brain
Why do we have so many cognitive biases? It turns out that our intuitive judgments—our gut reactions, our instincts, whatever you call them—aren't adapted for the modern environment. They evolved from the ancestral savanna environment, when we lived in small tribes of 15–150 people and spent our time hunting and foraging.
It's not a surprise, when you think about it. Evolution works on time scales of many thousands of years; our modern informational environment has been around for only a couple of decades, with the rise of the internet and social media.
Unfortunately, that means we're using brains adapted for the primitive conditions of hunting and foraging to judge information and make decisions in a very different world. In the ancestral environment, we had to make quick snap judgments in order to survive, thrive, and reproduce; we're the descendants of those who did so most effectively.
In the modern environment, we can take our time to make much better judgments by using structured evaluation processes to protect yourself from cognitive biases. We have to train our minds to go against our intuitions if we want to figure out the truth and avoid falling for misinformation.
Yet it feels very counterintuitive to do so. Again, not a surprise: by definition, you have to go against your intuitions. It's not easy, but it's truly the only path if you don't want to be vulnerable to fake news.
The Danger of Cognitive Fluency and Illusory Truth
We already make plenty of mistakes by ourselves, without outside intervention. It's especially difficult to protect ourselves against those who know how to manipulate us. Unfortunately, the purveyors of misinformation excel at exploiting our cognitive biases to get us to buy into fake news.
Consider the illusory truth effect. Our vulnerability to it stems from how our brain processes novel stimuli. The first time we hear something new to us, it's difficult to process mentally. It has to integrate with our existing knowledge framework, and we have to build new neural pathways to make that happen. Doing so feels uncomfortable for our lazy brain, so the statement that we heard seems difficult to swallow to us.
The next time we hear that same thing, our mind doesn't have to build new pathways. It just has to go down the same ones it built earlier. Granted, those pathways are little more than trails, newly laid down and barely used. It's hard to travel down that newly established neural path, but much easier than when your brain had to lay down that trail. As a result, the statement is somewhat easier to swallow.
Each repetition widens and deepens the trail. Each time you hear the same thing, it feels more true, comfortable, and intuitive.
Does it work for information that seems very unlikely? Science says yes! Researchers found that the illusory truth effect applies strongly to implausible as well as plausible statements.
What about if you know better? Surely prior knowledge prevents this illusory truth! Unfortunately not: even if you know better, research shows you're still vulnerable to this cognitive bias, though less than those who don't have prior knowledge.
Sadly, people who are predisposed to more elaborate and sophisticated thinking—likely you, if you're reading the article—are more likely to fall for the illusory truth effect. And guess what: more sophisticated thinkers are also likelier than less sophisticated ones to fall for the cognitive bias known as the bias blind spot, where you ignore your own cognitive biases. So if you think that cognitive biases such as the illusory truth effect don't apply to you, you're likely deluding yourself.
That's why the purveyors of misinformation rely on repeating the same thing over and over and over and over again. They know that despite fact-checking, their repetition will sway people, even some of those who think they're invulnerable. In fact, believing that you're invulnerable will make you more likely to fall for this and other cognitive biases, since you won't be taking the steps necessary to address them.
Other Important Cognitive Biases
What are some other cognitive biases you need to beware? If you've heard of any cognitive biases, you've likely heard of the "confirmation bias." That refers to our tendency to look for and interpret information in ways that conform to our prior beliefs, intuitions, feelings, desires, and preferences, as opposed to the facts.
Again, cognitive fluency deserves blame. It's much easier to build neural pathways to information that we already possess, especially that around which we have strong emotions; it's much more difficult to break well-established neural pathways if we need to change our mind based on new information. Consequently, we instead look for information that's easy to accept, that which fits our prior beliefs. In turn, we ignore and even actively reject information that doesn't fit our beliefs.
Moreover, the more educated we are, the more likely we are to engage in such active rejection. After all, our smarts give us more ways of arguing against new information that counters our beliefs. That's why research demonstrates that the more educated you are, the more polarized your beliefs will be around scientific issues that have religious or political value overtones, such as stem cell research, human evolution, and climate change. Where might you be letting your smarts get in the way of the facts?
Our minds like to interpret the world through stories, meaning explanatory narratives that link cause and effect in a clear and simple manner. Such stories are a balm to our cognitive fluency, as our mind constantly looks for patterns that explain the world around us in an easy-to-process manner. That leads to the "narrative fallacy," where we fall for convincing-sounding narratives regardless of the facts, especially if the story fits our predispositions and our emotions.
You ever wonder why politicians tell so many stories? What about the advertisements you see on TV or video advertisements on websites, which tell very quick visual stories? How about salespeople or fundraisers? Sure, sometimes they cite statistics and scientific reports, but they spend much, much more time telling stories: simple, clear, compelling narratives that seem to make sense and tug at our heartstrings.
Now, here's something that's actually true: the world doesn't make sense. The world is not simple, clear, and compelling. The world is complex, confusing, and contradictory. Beware of simple stories! Look for complex, confusing, and contradictory scientific reports and high-quality statistics: they're much more likely to contain the truth than the easy-to-process stories.
Another big problem that comes from cognitive fluency: the "attentional bias." We pay the most attention to whatever we find most emotionally salient in our environment, as that's the information easiest for us to process. Most often, such stimuli are negative; we feel a lesser but real attentional bias to positive information.
That's why fear, anger, and resentment represent such powerful tools of misinformers. They know that people will focus on and feel more swayed by emotionally salient negative stimuli, so be suspicious of negative, emotionally laden data.
You should be especially wary of such information in the form of stories framed to fit your preconceptions and repeated. That's because cognitive biases build on top of each other. You need to learn about the most dangerous ones for evaluating reality clearly and making wise decisions, and watch out for them when you consume news, and in other life areas where you don't want to make poor choices.
Fixing Our Brains
Unfortunately, knowledge only weakly protects us from cognitive biases; it's important, but far from sufficient, as the study I cited earlier on the illusory truth effect reveals.
What can we do?
The easiest decision aid is a personal commitment to twelve truth-oriented behaviors called the Pro-Truth Pledge, which you can make by signing the pledge at ProTruthPledge.org. All of these behaviors stem from cognitive neuroscience and behavioral economics research in the field called debiasing, which refers to counterintuitive, uncomfortable, but effective strategies to protect yourself from cognitive biases.
What are these behaviors? The first four relate to you being truthful yourself, under the category "share truth." They're the most important for avoiding falling for cognitive biases when you share information:
- Verify: fact-check information to confirm it is true before accepting and sharing it
- Balance: share the whole truth, even if some aspects do not support my opinion
- Cite: share my sources so that others can verify my information
- Clarify: distinguish between my opinion and the facts
The second set of four are about how you can best "honor truth" to protect yourself from cognitive biases in discussions with others:
- Acknowledge: when others share true information, even when we disagree otherwise
- Reevaluate: if my information is challenged, retract it if I cannot verify it
- Defend: defend others when they come under attack for sharing true information, even when we disagree otherwise
- Align: align my opinions and my actions with true information
The last four, under the category "encourage truth," promote broader patterns of truth-telling in our society by providing incentives for truth-telling and disincentives for deception:
- Fix: ask people to retract information that reliable sources have disproved even if they are my allies
- Educate: compassionately inform those around me to stop using unreliable sources even if these sources support my opinion
- Defer: recognize the opinions of experts as more likely to be accurate when the facts are disputed
- Celebrate: those who retract incorrect statements and update their beliefs toward the truth
Peer-reviewed research has shown that taking the Pro-Truth Pledge is effective for changing people's behavior to be more truthful, both in their own statements and in interactions with others. I hope you choose to join the many thousands of ordinary citizens—and over 1,000 politicians and officials—who committed to this decision aid, as opposed to going with their gut.
[Adapted from: Dr. Gleb Tsipursky and Tim Ward, Pro Truth: A Practical Plan for Putting Truth Back Into Politics (Changemakers Books, 2020).]
[Editor's Note: To read other articles in this special magazine issue, visit the beautifully designed e-reader version.]
Friday Five: The Therapeutic Value of Bonding with Fellow Sports Fans
The Friday Five covers five stories in research that you may have missed this week. There are plenty of controversies and troubling ethical issues in science – and we get into many of them in our online magazine – but this news roundup focuses on new scientific theories and progress to give you a therapeutic dose of inspiration headed into the weekend.
This episode includes an interview with Dr. Helen Keyes, Head of the School of Psychology and Sports Science at Anglia Ruskin University.
Listen on Apple | Listen on Spotify | Listen on Stitcher | Listen on Amazon | Listen on Google
- Attending sports events is linked to greater life satisfaction
- Identifying specific brain tumors in under 90 seconds with AI
- LSD - minus hallucinations - raises hopes for mental health
- New research on the benefits of cold showers
- Inspire awe in your kids and reap the benefits
Matt Fuchs is the editor-in-chief of Leaps.org and Making Sense of Science. He is also a contributing reporter to the Washington Post and has written for the New York Times, Time Magazine, WIRED and the Washington Post Magazine, among other outlets. Follow him @fuchswriter.
Scientists and dark sky advocates team up to flip the switch on light pollution
As a graduate student in observational astronomy at the University of Arizona during the 1970s, Diane Turnshek remembers the starry skies above the Kitt Peak National Observatory on the Tucson outskirts. Back then, she could observe faint objects like nebulae, galaxies, and star clusters on most nights.
When Turnshek moved to Pittsburgh in 1981, she found it almost impossible to see a clear night sky because the city’s countless lights created a bright dome of light called skyglow. Over the next two decades, Turnshek almost forgot what a dark sky looked like. She witnessed pristine dark skies in their full glory again during a visit to the Mars Desert Research Station in Utah in early 2000s.
“I was shocked at how beautiful the dark skies were in the West. That is when I realized that most parts of the world have lost access to starry skies because of light pollution,” says Turnshek, an astronomer and lecturer at Carnegie Mellon University. In 2015, she became a dark sky advocate.
Light pollution is defined as the excessive or wasteful use of artificial light.
Light-emitting diodes (LEDs) -- which became commercially available in 2002 and rapidly gained popularity in offices, schools, and hospitals when their price dropped six years later — inadvertently fueled the surge in light pollution. As traditional light sources like halogen, fluorescent, mercury, and sodium vapor lamps have been phased out or banned, LEDs became the main source of lighting globally in 2019. Switching to LEDs has been lauded as a win-win decision. Not only are they cheap but they also consume a fraction of electricity compared to their traditional counterparts.
But as cheap LED installations became omnipresent, they increased light pollution. “People have been installing LEDs thinking they are making a positive change for the environment. But LEDs are a lot brighter than traditional light sources,” explains Ashley Wilson, director of conservation at the International Dark-Sky Association (IDA). “Despite being energy-efficient, they are increasing our energy consumption. No one expected this kind of backlash from switching to LEDs.”
Light pollution impacts the circadian rhythms of all living beings — the natural internal process that regulates the sleep–wake cycle.
Currently, more than 80 percent of the world lives under light-polluted skies. In the U.S. and Europe, that figure is above 99 percent.
According to the IDA, $3 billion worth of electricity is lost to skyglow every year in the U.S. alone — thanks to unnecessary and poorly designed outdoor lighting installations. Worse, the resulting light pollution has insidious impacts on humans and wildlife — in more ways than one.
Disrupting the brain’s clock
Light pollution impacts the circadian rhythms of all living beings—the natural internal process that regulates the sleep–wake cycle. Humans and other mammals have neurons in their retina called intrinsically photosensitive retinal ganglion cells (ipRGCs). These cells collect information about the visual world and directly influence the brain’s biological clock in the hypothalamus.
The ipRGCs are particularly sensitive to the blue light that LEDs emit at high levels, resulting in suppression of melatonin, a hormone that helps us sleep. A 2020 JAMA Psychiatry study detailed how teenagers who lived in areas with bright outdoor lighting at night went to bed late and slept less, which made them more prone to mood disorders and anxiety.
“Many people are skeptical when they are told something as ubiquitous as lights could have such profound impacts on public health,” says Gena Glickman, director of the Chronobiology, Light and Sleep Lab at Uniformed Services University. “But when the clock in our brains gets exposed to blue light at nighttime, it could result in a lot of negative consequences like impaired cognitive function and neuro-endocrine disturbances.”
In the last 12 years, several studies indicated that light pollution exposure is associated with obesity and diabetes in humans and animals alike. While researchers are still trying to understand the exact underlying mechanisms, they found that even one night of too much light exposure could negatively affect the metabolic system. Studies have linked light pollution to a higher risk of hormone-sensitive cancers like breast and prostate cancer. A 2017 study found that female nurses exposed to light pollution have a 14 percent higher risk of breast cancer. The World Health Organization (WHO) identified long-term night shiftwork as a probable cause of cancer.
“We ignore our biological need for a natural light and dark cycle. Our patterns of light exposure have consequently become different from what nature intended,” explains Glickman.
Circadian lighting systems, designed to match individuals’ circadian rhythms, might help. The Lighting Research Center at Rensselaer Polytechnic Institute developed LED light systems that mimic natural lighting fluxes, required for better sleep. In the morning the lights shine brightly as does the sun. After sunset, the system dims, once again mimicking nature, which boosts melatonin production. It can even be programmed to increase blue light indoors when clouds block sunlight’s path through windows. Studies have shown that such systems might help reduce sleep fragmentation and cognitive decline. People who spend most of their day indoors can benefit from such circadian mimics.
When Diane Turnshek moved to Pittsburgh, she found it almost impossible to see a clear night sky because the city’s countless lights created a bright dome of light called skyglow.
Leading to better LEDs
Light pollution disrupts the travels of millions of migratory birds that begin their long-distance journeys after sunset but end up entrapped within the sky glow of cities, becoming disoriented. A 2017 study in Nature found that nocturnal pollinators like bees, moths, fireflies and bats visit 62 percent fewer plants in areas with artificial lights compared to dark areas.
“On an evolutionary timescale, LEDs have triggered huge changes in the Earth’s environment within a relative blink of an eye,” says Wilson, the director of IDA. “Plants and animals cannot adapt so fast. They have to fight to survive with their existing traits and abilities.”
But not all types of LEDs are inherently bad -- it all comes down to how much blue light they emit. During the day, the sun emits blue light waves. By sunset, it’s replaced by red and orange light waves that stimulate melatonin production. LED’s artificial blue light, when shining at night, disrupts that. For some unknown reason, there are more bluer color LEDs made and sold.
“Communities install blue color temperature LEDs rather than redder color temperature LEDs because more of the blue ones are made; they are the status quo on the market,” says Michelle Wooten, an assistant professor of astronomy at the University of Alabama at Birmingham.
Most artificial outdoor light produced is wasted as human eyes do not use them to navigate their surroundings.
While astronomers and the IDA have been educating LED manufacturers about these nuances, policymakers struggle to keep up with the growing industry. But there are things they can do—such as requiring LEDs to include dimmers. “Most LED installations can be dimmed down. We need to make the dimmable drivers a mandatory requirement while selling LED lighting,” says Nancy Clanton, a lighting engineer, designer, and dark sky advocate.
Some lighting companies have been developing more sophisticated LED lights that help support melatonin production. Lighting engineers at Crossroads LLC and Nichia Corporation have been working on creating LEDs that produce more light in the red range. “We live in a wonderful age of technology that has given us these new LED designs which cut out blue wavelengths entirely for dark-sky friendly lighting purposes,” says Wooten.
Dimming the lights to see better
The IDA and advocates like Turnshek propose that communities turn off unnecessary outdoor lights. According to the Department of Energy, 99 percent of artificial outdoor light produced is wasted as human eyes do not use them to navigate their surroundings.
In recent years, major cities like Chicago, Austin, and Philadelphia adopted the “Lights Out” initiative encouraging communities to turn off unnecessary lights during birds’ peak migration seasons for 10 days at a time. “This poses an important question: if people can live without some lights for 10 days, why can’t they keep them turned off all year round,” says Wilson.
Most communities globally believe that keeping bright outdoor lights on all night increases security and prevents crime. But in her studies of street lights’ brightness levels in different parts of the US — from Alaska to California to Washington — Clanton found that people felt safe and could see clearly even at low or dim lighting levels.
Clanton and colleagues installed LEDs in a Seattle suburb that provided only 25 percent of lighting levels compared to what they used previously. The residents reported far better visibility because the new LEDs did not produce glare. “Visual contrast matters a lot more than lighting levels,” Clanton says. Additionally, motion sensor LEDs for outdoor lighting can go a long way in reducing light pollution.
Flipping a switch to preserve starry nights
Clanton has helped draft laws to reduce light pollution in at least 17 U.S. states. However, poor awareness of light pollution led to inadequate enforcement of these laws. Also, getting thousands of counties and municipalities within any state to comply with these regulations is a Herculean task, Turnshek points out.
Fountain Hills, a small town near Phoenix, Arizona, has rid itself of light pollution since 2018, thanks to the community's efforts to preserve dark skies.
Until LEDs became mainstream, Fountain Hills enjoyed starry skies despite its proximity to Phoenix. A mountain surrounding the town blocks most of the skyglow from the city.
“Light pollution became an issue in Fountain Hills over the years because we were not taking new LED technologies into account. Our town’s lighting code was antiquated and out-of-date,” says Vicky Derksen, a resident who is also a part of the Fountain Hills Dark Sky Association founded in 2017. “To preserve dark skies, we had to work with the entire town to update the local lighting code and convince residents to follow responsible outdoor lighting practices.”
Derksen and her team first tackled light pollution in the town center which has a faux fountain in the middle of a lake. “The iconic centerpiece, from which Fountain Hills got its name, had the wrong types of lighting fixtures, which created a lot of glare,” adds Derksen. They then replaced several other municipal lighting fixtures with dark-sky-friendly LEDs.
The results were awe-inspiring. After a long time, residents could see the Milky Way with crystal clear clarity. Star-gazing activities made a strong comeback across the town. But keeping light pollution low requires constant work.
Derksen and other residents regularly measure artificial light levels in
Fountain Hills. Currently, the only major source of light pollution is from extremely bright, illuminated signs which local businesses had installed in different parts of the town. While Derksen says it is an uphill battle to educate local businesses about light pollution, Fountain Hills residents are determined to protect their dark skies.
“When a river gets polluted, it can take several years before clean-up efforts see any tangible results,” says Derksen. “But the effects are immediate when you work toward reducing light pollution. All it requires is flipping a switch.”