by Sarika Tilwani
It is paradoxical that in the age of information overload and easy access to facts, misinformation spreads rapidly and sticks stubbornly. Why? The answer partly lies in how our brains are wired.
Making Sense of the World
Our beliefs are formed by our personal experiences, cultural influences, and social interactions all of which shape our worldview [1]. We rely on our beliefs for making quick decisions – such as how to travel to work, or whether to have breakfast now or grab something later or which social event to attend. Rather than constantly re-evaluating every input, the brain uses stored beliefs to predict outcomes and guide behavior [2]. From an evolutionary perspective, this reliance on beliefs is advantageous, as it confers a survival benefit, allowing individuals to act quickly and maintain social bonds despite the risk of occasional mistakes [3].
Repetition Breeds Belief
Repeated statements are perceived to be more accurate irrespective of the source of information. This phenomenon, known as “The Illusory Truth Effect” has been shown to be true across various domains, including news, trivia and advertisements [4]. A single repetition of a false statement increases its chances of being shared on social media even if it contradicts prior knowledge [5, 6]. In fact, this phenomenon was also observed in individuals who believed in climate change, but repeated misinformation made them skeptical of these claims [7]. This effect was widespread during the COVID-19 pandemic and is increasingly evident in the rise of vaccine hesitancy, racism, religious polarization, and other forms of social division.
Emotion over Evidence
How we process information is strongly influenced by emotion. Misinformation that evokes fear, anger, or outrage leads to the activation of the amygdala, the brain’s emotion-processing center, and is less likely to be corrected [8]. These emotions can override the prefrontal cortex, which is responsible for critical thinking and reasoning [9]. For instance, a study measuring brain activity showed that even briefly viewed angry faces, too fast to be consciously noticed, trigger the amygdala and affect how the prefrontal cortex evaluates emotional expressions, highlighting how emotion can shape our perception before we are even aware of it [10].
Confirmation Bias
The tendency to believe information that aligns with pre-existing beliefs while ignoring or dismissing contradictory evidence is known as confirmation bias. It could also lead to actively seeking out information that confirms their bias and to being dismissive towards any contradiction [11]. This is evident in the way people curate their social media feeds, follow like-minded influencers, and consume news from ideologically aligned outlets, which creates echo chambers. A study demonstrated that individuals having prior negative bias about GM (genetically modified) crops spent less time evaluating alternative viewpoints in web search results, instead focusing more on links that supported their existing beliefs [12].
Reward of being right
Information that supports our beliefs leads to the release of dopamine, a neurotransmitter which plays a central role in reinforced learning and decision making. This chemical reinforcement strengthens our beliefs and makes us more likely to seek out similar information, creating a feedback loop [13]. In an experiment based on an attention task, individuals involuntarily focused more on previously rewarded stimuli demonstrating the lasting impact of dopamine release [14].
Can it be corrected?
Changing deeply held beliefs is challenging, and simply telling someone they’re wrong often backfires, as it can feel like a personal attack. As individuals, we need to pause and think deliberately about what we believe in and why we believe it. We should strive to understand whether that belief stems from our prior knowledge, our personal biases, or is based on evidence, and should be willing to reassess our personal stance on issues. Studies have shown that just being aware of the concept of confirmation bias reduces our susceptibility to misinformation [11]. One way to guard against misinformation is to rely on curated, credible sources that are grounded in evidence rather than unchecked opinions. Misinformation isn’t just a technology problem, it’s a human one as well. Technology accelerates the spread; to believe it or not, is on us!
References:
- Seitz, R. J. (2022) Believing and Beliefs-Neurophysiological Underpinnings, Frontiers in behavioral neuroscience. 16, 880504.
- Bottemanne, H. (2025) Bayesian brain theory: Computational neuroscience of belief, Neuroscience. 566, 198-204.
- Bragazzi, N. L. & Garbarino, S. (2024) Understanding and Combating Misinformation: An Evolutionary Perspective, JMIR infodemiology. 4, e65521.
- Bell, R., Nadarevic, L., Mieth, L. & Buchner, A. (2025) The illusory-truth effect and its absence under accuracy-focused processing are robust across contexts of low and high advertising exposure, Cognitive research: principles and implications. 10, 21.
- Vellani, V., Zheng, S., Ercelik, D. & Sharot, T. (2023) The illusory truth effect leads to the spread of misinformation, Cognition. 236, 105421.
- Hassan, A. & Barber, S. J. (2021) The effects of repetition frequency on the illusory truth effect, Cognitive research: principles and implications. 6, 38.
- Jiang, Y., Schwarz, N., Reynolds, K. J. & Newman, E. J. (2024) Repetition increases belief in climate-skeptical claims, even for climate science endorsers, PloS one. 19, e0307294.
- Edelson, M., Sharot, T., Dolan, R. J. & Dudai, Y. (2011) Following the crowd: brain substrates of long-term memory conformity, Science. 333, 108-11.
- Arnsten, A. F. (2009) Stress signalling pathways that impair prefrontal cortex structure and function, Nature reviews Neuroscience. 10, 410-22.
- Nomura, M., Ohira, H., Haneda, K., Iidaka, T., Sadato, N., Okada, T. & Yonekura, Y. (2004) Functional association of the amygdala and ventral prefrontal cortex during cognitive evaluation of facial expressions primed by masked angry faces: an event-related fMRI study, NeuroImage. 21, 352-63.
- Piksa, M., Noworyta, K., Gundersen, A., Kunst, J., Morzy, M., Piasecki, J. & Rygula, R. (2024) The impact of confirmation bias awareness on mitigating susceptibility to misinformation, Frontiers in public health. 12, 1414864.
- Suzuki, M. & Yamamoto, Y. (2021) Characterizing the Influence of Confirmation Bias on Web Search Behavior, Frontiers in psychology. 12, 771948.
- Chakroun, K., Wiehler, A., Wagner, B., Mathar, D., Ganzer, F., van Eimeren, T., Sommer, T. & Peters, J. (2023) Dopamine regulates decision thresholds in human reinforcement learning in males, Nature communications. 14, 5369.
- Anderson, B. A., Kuwabara, H., Wong, D. F., Gean, E. G., Rahmim, A., Brasic, J. R., George, N., Frolov, B., Courtney, S. M. & Yantis, S. (2016) The Role of Dopamine in Value-Based Attentional Orienting, Current biology : CB. 26, 550-5.
Author:
Sarika Tilwani completed her Ph.D. in Life Sciences from TMC-ACTREC (Tata Memorial Centre-Advanced Centre for Treatment Research & Education in Cancer) where she studied the role of 14-3-3 proteins in centrosome biology and skin differentiation. When not at the bench or in front of the computer, she can be found exploring new books or experimenting with recipes. She genuinely believes that complex science can be made as clear as Sherlock’s deductions and as captivating as Watson’s tales.
Cover image: Created by the author on Microsoft Bing and edited with Google Gemini
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This article was written as part of Club SciWri’s first Science Writing Workshop, an initiative aimed at nurturing new voices in science communication and helping participants explore how to make complex ideas accessible to wider audiences.
Workshop conducted by Saurja Dasgupta, Sumbul Jawed Khan, Ananya Sen , Rohini Subrahmanyam, and Roopsha Sengupta
