The Brain’s Hidden Vulnerability: How Misinformation Rewires What We Believe

In today’s world, you don’t need a head injury to disrupt your brain: you just need a scroll through social media. A viral post claims a miracle cure. A headline sparks outrage. A video sounds convincing enough to share without a second thought. Is it harmless? Maybe. But repeated exposure to false information doesn’t just influence what we think; it may subtly change how our brains process truth itself.

The brain is designed to make quick decisions. It relies on mental shortcuts: patterns, past experiences, and emotional cues to help us manage an overwhelming amount of information. Most of the time, this works in our favor. But in an environment flooded with misleading or false content, those same shortcuts can be exploited. Let’s break down what misinformation is, how it affects your brain, and why your mind is more vulnerable than you might think.

What is misinformation, and why does it spread so easily?

Misinformation refers to false or misleading information that is shared without the intent to deceive.^[1] Unlike deliberate disinformation, which is created to mislead, misinformation often spreads because it sounds believable, matches existing beliefs, or triggers a strong emotional response.^[2] That’s the key: emotion drives attention.

Content that triggers strong emotions, such as fear, anger, or surprise, is more likely to be remembered and shared.^[2] Social media platforms magnify this effect, rewarding creators for engagement over accuracy. The result is an environment where emotionally charged information travels faster and farther than carefully vetted facts.

What happens in your brain when you encounter misinformation?

Here’s where neuroscience comes in:

1. Cognitive shortcuts (heuristics): Your brain favors efficiency over accuracy. Instead of evaluating every detail, it relies on common patterns or “gut feelings” to decide what seems true.^[3]

2. Reward circuitry activation: When information supports what you already believe, your brain’s reward system, specifically dopamine pathways, lights up.^[4] This sense of validation reinforces the belief, even if the information is incorrect.

3. Amygdala and emotional tagging: Emotionally charged content activates a core part of the brain called the amygdala, making the information feel more important and committing it to memory.^[5] In particular, fear-based misinformation can become deeply ingrained.^[5]

4. Repetition effect (illusory truth effect): The more often you encounter a piece of information, the more likely your brain is to interpret it as true, even if you originally thought it was false.^{[3, 6]} Familiarity breeds perceived accuracy.

5. Brain fatigue: Critical thinking requires the effort of a part of the brain called the prefrontal cortex. When you’re tired, overwhelmed, or distracted, the prefrontal cortex tires out, and the brain is more likely to default to quick judgments as opposed to careful analysis.

Why misinformation tends to be so hard to correct

Once misinformation is encoded, it doesn’t simply disappear when corrected.

Your brain builds internal frameworks that help make sense of the world. When misinformation becomes woven into that mental framework, removing it can feel like ripping out a structural support. Even when presented with accurate information, the original false belief can linger. This is known as the “continued influence effect,” in which outdated or incorrect information still shapes thinking and decision-making processes.^[7]

The real-life consequences

Misinformation isn’t just an abstract problem; it has concrete effects on health, behavior, and society.

It can:

• Influence medical decisions, including vaccine hesitancy or the use of unproven treatments.

• Increase anxiety or fear around misunderstood risks.

• Deepen social divisions via reinforcing polarized beliefs.

• Weaken trust in institutions, including scientific and medical systems.

Much like mild brain injuries, the effects may not be immediately obvious but over time, they can accumulate.

Can your brain recover from misinformation?

The good news is that the brain is adaptable! Thanks to a process called neuroplasticity, beliefs and thought patterns can change, though it may demand intentional effort.

Correcting misinformation isn’t just about providing facts. It involves:

• Replacing false information with clear, accurate explanations.

• Repeating correct information over time.

• Engaging critical thinking rather than passive consumption.

In other words, unlearning takes just as much reinforcement as learning.

How to protect your brain from misinformation

While you can’t avoid all misleading information, you can reduce its impact.

Here are a few ways to safeguard your thinking:

• Pause before sharing anything that feels emotionally charged.

• Check the source: credible, peer-reviewed information matters.

• Be cautious of sensational headlines designed to provoke strong reactions.

• Seek multiple perspectives, especially from trusted experts.

• Stay aware of your own biases; what feels true isn’t always accurate.

Misinformation doesn’t need to be loud or obvious to have an effect. It can be subtle, repeated, and quietly influential, shaping beliefs over time. Your brain is incredibly powerful, but it’s not immune to manipulation. In a place where information moves faster than ever, protecting your mind isn’t just important: it’s essential.

By Christy Kestner, PhD

References:

1. Bragazzi NL, Garbarino S. Understanding and combating misinformation: An evolutionary perspective. JMIR infodemiology. 2024 Dec 27;4(1):e65521. https://doi.org/10.2196/65521

2. Piksa M, Noworyta K, Gundersen A, Kunst J, Morzy M, Piasecki J, Rygula R. The impact of confirmation bias awareness on mitigating susceptibility to misinformation. Frontiers in Public Health. 2024 Oct 15;12:1414864. https://doi.org/10.3389/fpubh.2024.1414864

3. Hassan A, Barber SJ. The effects of repetition frequency on the illusory truth effect. Cognitive research: principles and implications. 2021 May 13;6(1):38. https://doi.org/10.1186/s41235-021-00301-5

4. Schultz W. Dopamine reward prediction error coding. Dialogues in clinical neuroscience. 2016 Mar 31;18(1):23-32. https://doi.org/10.31887/DCNS.2016.18.1/wschultz

5. Chau LS, Galvez R. Amygdala's involvement in facilitating associative learning-induced plasticity: a promiscuous role for the amygdala in memory acquisition. Frontiers in integrative neuroscience. 2012 Oct 10;6:92. https://doi.org/10.3389/fnint.2012.00092

6. Vellani V, Zheng S, Ercelik D, Sharot T. The illusory truth effect leads to the spread of misinformation. Cognition. 2023 Jul 1;236:105421. https://doi.org/10.1016/j.cognition.2023.105421

7. Chan MP, Jones CR, Hall Jamieson K, Albarracín D. Debunking: A meta-analysis of the psychological efficacy of messages countering misinformation. Psychological science. 2017 Nov;28(11):1531-46. https://doi.org/10.1177/0956797617714579