Flying in the Face of Facts: Denialism, Anosognosia, and the Human Brain

Introduction

When someone refuses to accept an empirically verifiable reality, they call upon irrational thought processes and behaviors that produce denialism. People often process information to reach conclusions driven not by rational analysis, but by specific motivations or beliefs. Lack of trust in scientific institutions, governmental authority, or experts can foster thinking that runs counter to facts.

Protection of Beliefs

Humans have developed many defense mechanisms or unconscious strategies to protect their psyches against disturbing ideas and facts, a phenomenon referred to as cognitive dissonance. We all have a tendency to form beliefs about social or moral dangers that reinforce and reflect our particular social or cultural group’s visions of an ideal society. This is especially true with regard to beliefs about ideas that imperil our way of life or fundamental values. This is called cultural cognition and protects our identity by assigning credit or evidence to the beliefs of the group we identify with. For example, the motivated reasoning/cultural cognition behind believing that autism is caused by vaccines, despite the scientific consensus that this is not the case, might result from not wanting to alienate or lose one’s place in a political group or religious community.

Lack of intelligence or education do not create denialism. Rather, complex psychological and social mechanisms that protect identity and group membership are the primary features that explain why some hold onto beliefs that are based on falsehoods in the face of rational counterarguments. Understanding these processes is critical for science communications and public health messaging. People in the United States have become more skeptical about “experts,” those with specialized education and training, including scientists, physicians, lawyers and judges, and scholars. Where people get their information is also critical. With the intense flooding of our in-boxes and social media feeds, it has become increasingly difficult for any of us to cull fact from fiction, conspiracy theory from evidence-based research.

Some people engage in thought processes that deny scientific findings and see scientific consensus itself as a conspiracy of the “deep state.” They may cherry-pick facts or use fake experts or falsified data to strengthen their arguments. Denialists may misunderstand scientific methods and hold science to an impossible standard of “truth.” With trolls and instigators dominating social media and the vast majority of lay research taking place on the internet, misrepresentations and logical fallacies are available to anyone to bolster inaccurate beliefs. Highly polarizing partisan politics in which both sides demonize the other now play a major role in spreading science and history denialism.

Intentional ignorance differs from denialism. Instead of deriving from sources that mislead, this form of ignorance involves a conscious and deliberate avoidance of facts or information in order to protect one’s beliefs. Some sources deliberately distort facts in order to gain followers, or uphold a view for personal gain or to justify bias or prejudice. For example, people who gain from the profits of oil companies may minimize or deliberately deny that climate change is occurring.

Anosognosia

Anosognosia is a neurological condition seen primarily in stroke patients who have suffered injury to the right hemisphere of the brain. Patients with this condition genuinely lack awareness or recognition of their deficits following brain injury, most commonly a stroke. This condition is not denialism created as a psychological defense or based on motivated reasoning. It is, instead, a direct result of damage to specific brain regions (usually the right parietal cortex) responsible for self-awareness and monitoring. Patients cannot perceive some or all of their deficits due to this damage. Return of awareness may come with recovery processes and rehabilitation in anosognosia cases.

Anosognosia after stroke is fundamentally different from denialism, although the two phenomena may appear similar at first glance, and both may lessen over time with increased awareness. The key distinction lies in their underlying mechanisms and nature. Denialism requires intact cognitive and perceptual abilities. Denialists use active strategies to avoid confronting unwanted truths, rejecting evidence or information presented by experts by using psychological, social, and ideological resistance. If the motivations or experience or awareness of denialists change, they can sometimes acknowledge reality and evidence.

In patients with anosognosia after a brain injury, psychological factors may also be at play. Patients who begin to regain some awareness might develop secondary psychological defenses against confronting their disabilities. Some patients may have partial awareness of their impairments and then develop psychological denial mechanisms when they are confronted with the full extent of their deficits. Family members of stroke patients sometimes engage in denialism about prognosis or deficits, and this form of denial is psychologically motivated. People don’t want to entertain a difficult prognosis for a loved one. With both denialism and anosognosia, people resist accepting information that challenges their sense of themselves and their place in the world.

Anosognosia requires rehabilitation approaches and often improves with brain recovery. Denialism requires empathic communication and exposure to facts and information in a way that acknowledges a person’s need not to accept the truth.

Approaches to Address Science Denialism

One preventive strategy to address science denialism is called a psychological inoculation message. This involves a forewarning that certain misleading arguments aim to change people's attitudes and that people are vulnerable to believing these arguments; the forewarning also entails pre-bunking — warning people about tactics that, for example, include “fake news.” Exposing manipulation techniques —including tactics such as polarizing language, relying on fake experts, and creating conspiracy theories — can help prevent people from accepting misinformation they haven’t preciously seen or heard.

Education is another useful strategy. Beliefs that are counter to scientific information can be altered by training people in scientific reasoning and promoting an understanding of scientific methods. Teaching people to read media sources, including social media, and other information sources with a critical approach can be helpful. Teaching people about what education and training is necessary for becoming an expert in a particular field of knowledge lends credence to reputable sources of information.

Other effective persuasion methods include fact corrections in response to science deniers’ statements, if done publicly and respectfully, and presenting scientific consensus points with real data, but not in overwhelming amounts. In any effort to change someone’s mind, it’s important to acknowledge the uncertainties inherent in current scientific knowledge. Respecting people’s thoughts, values, concerns, and fears is crucial in any communication meant to sway beliefs.

Deliberate distortion of facts by bad actors, or intentional ignorance on the part of a person intent on maintaining set beliefs, present greater threats and are challenging to combat. These situations, especially when they affect groups rather than just individuals, require delicate interpersonal strategies such as active listening and open-mindedness combined with accurate information and authoritative references that may incrementally cultivate critical thinking. Public awareness campaigns can work on a larger scale if they thoughtfully employ these techniques.

Key References

Acharya AB, Sánchez-Manso JC. Anosognosia. [Updated 2023 Apr 24]. In: StatPearls Treasure Island (FL): StatPearls Publishing; 2025 Jan-. Available from: https://www.ncbi.nlm.nih.gov/books/NBK513361/

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