khirstyn

Author:

Khirstyn-Lien

Neuroscience and Cognitive Science

Date: July 2025

Abstract
In the following perspective based review, I explore the hypothesis that individuals who frequently lie or habitually alter their perception of reality may be at increased risk of developing dementia. Drawing upon existing neuroscientific literature on executive function, memory distortion, and prefrontal cortex integrity, I propose that chronic deception may not only tax key cognitive systems but could also reflect or accelerate early stage neurodegeneration. This review was prompted from my volunteer work in my younger years at a hospice center I frequently volunteered at. Nurses told me that they correlated patients who were described as people who lied frequently in their younger years by people close to them were often the patients who had dementia. By examining the neural correlates of lying and reality monitoring, particularly within the prefrontal cortex and medial temporal lobe, I argue that these behaviors may serve as behavioral biomarkers of future cognitive decline. Furthermore, I consider the sociopsychological consequences of deception, such as social isolation and chronic stress, as potential compounding risk factors for dementia.

Introduction
With attribute to my experience in neuroscience research, I have long been fascinated by the subtle behavioral changes that precede overt cognitive decline. In adolescence we are taught morally (most of us) that lying is wrong and that we should always be truthful. Good character seems to not be enough of a reason to some people to not lie, so I will dive into the science backed benefits of not being a chronic liar not to persuade but to inform those who believe lying has no effect on them as long as they do not get caught.

One such behavior, often dismissed as a character flaw or psychological defense, is chronic lying. In both clinical and social contexts, I have observed individuals who compulsively alter facts, embellish memories, or fabricate entire narratives. So much so that they often begin to believe their distorted reality. This prompted a deeper inquiry: could such persistent distortion of reality be an early behavioral marker of neurodegeneration? Or worse, could it contribute to long term structural and functional brain changes that increase the risk of dementia?

Executive Function and the Neuroscience of Deception
Lying is a cognitively demanding act that engages multiple regions of the brain, particularly the prefrontal cortex (PFC). Functional MRI studies (e.g., Spence et al., 2001; Abe et al., 2006) show that deception activates the dorsolateral PFC, anterior cingulate cortex, and orbitofrontal cortex, regions responsible for working memory, impulse control, and reality monitoring.

In chronic liars, structural neuroimaging has revealed reduced gray matter volume in the PFC, particularly the ventromedial and dorsolateral regions (Yang et al., 2005). Interestingly, these same regions are implicated in early stage dementia, including frontotemporal dementia (FTD) and Alzheimer’s disease (AD). The parallel degeneration in areas responsible for executive control and moral reasoning raises important questions about the directionality and causality of these patterns.

Confabulation and Memory Distortion
Another intersection between lying and dementia lies in the phenomenon of confabulation. This is the unconscious creation of false memories. Confabulation is commonly observed in Korsakoff’s syndrome, FTD, and even early Alzheimer’s disease, where patients unknowingly fabricate plausible stories to fill memory gaps. I hypothesize that in neurotypical individuals who regularly lie, particularly about autobiographical events, there may be a progressive weakening of the reality-monitoring mechanisms in the hippocampus, medial temporal lobe, and PFC.

These neural disruptions may set the stage for future impairment in source memory, a key component of episodic recall. Over time, the brain’s ability to distinguish between fact and fiction may degrade, first behaviorally, and later structurally.

Chronic Stress, Social Isolation, and Allostatic Load
Beyond the neural demands of lying, I also considered the psychosocial consequences. Individuals who routinely lie often experience increased stress, emotional dysregulation, and social disconnection each of which are independently linked to heightened dementia risk (Wilson et al., 2007; Cacioppo & Hawkley, 2009). Chronic activation of the hypothalamic-pituitary-adrenal (HPA) axis elevates cortisol levels and contributes to hippocampal atrophy, another hallmark of Alzheimer’s pathology.

Moreover, lying can result in broken relationships, loss of trust, and reputational damage, which can foster isolation, a factor that increases dementia risk by as much as 40% according to recent meta-analyses (Penninkilampi et al., 2018).

Discussion
While lying itself may not be a direct causative agent of dementia, the cognitive load, neural changes, and social sequelae associated with chronic deception may collectively increase vulnerability to neurodegenerative disease. My view is that habitual reality distortion may serve as an early warning sign, or even a prodromal behavior, particularly in individuals genetically predisposed to cognitive decline.

Future longitudinal studies should examine whether self-reported or observed lying frequency correlates with biomarkers of neurodegeneration (e.g., tau deposition, cortical thinning, hippocampal volume loss). Incorporating behavioral markers into early dementia screening protocols may allow for earlier intervention and improved outcomes.

Conclusion
In this article, I present a theoretical framework linking chronic lying and reality distortion to the development of dementia. While further research is required to establish causality, the current neuroscientific literature suggests that these behaviors are far from benign. Instead, they may reflect early dysfunction in brain systems that are critical for memory, reality monitoring, and self-awareness. I urge clinicians, researchers, and caregivers to view persistent deceptive behaviors not merely as moral failings but as possible early neurocognitive symptoms deserving of careful observation.

I predict not altering memories to be better or worse than they actually were will preserve brain function long term. No blocking out memories, no deleting images, no distortion of the past, present, or future. One key theme of life being to forgive, but not to forget.

References

Abe, N. et al. (2006). Neural correlates of true memory, false memory, and deception. Cerebral Cortex, 16(9), 1193–1199.

Cacioppo, J. T., & Hawkley, L. C. (2009). Perceived social isolation and cognition. Trends in Cognitive Sciences, 13(10), 447–454.

Penninkilampi, R., Casey, A. N., Singh, M. F., & Brodaty, H. (2018). The association between social engagement, loneliness, and risk of dementia. Journal of Alzheimer’s Disease, 66(4), 1619–1633.

Spence, S. A. et al. (2001). A cognitive neurobiological account of deception: Evidence from functional neuroimaging. Philosophical Transactions of the Royal Society B, 356(1413), 1185–1192.

Wilson, R. S., Krueger, K. R., Arnold, S. E., et al. (2007). Loneliness and risk of Alzheimer disease. Archives of General Psychiatry, 64(2), 234–240.

Yang, Y., Raine, A., Lencz, T., Bihrle, S., Lacasse, L., & Colletti, P. (2005). Prefrontal structural and functional abnormalities in people who lie pathologically. British Journal of Psychiatry, 187(4), 320–325.