Welcome to this first exploration of the intersection between one of the world's oldest strategy games and neuroscience. As an enthusiast neuro-engineer, I spend a lot of time analyzing how the brain works — and when I play chess, I realize I am essentially running a real-time cognitive experiment on myself.
Today, we focus on a specific and underrated dimension of chess: the fight against your own brain. We tend to think of a chess match as two brains competing against each other, but one of the most critical battles takes place entirely within your own mind. What happens when you have to abandon a plan you've spent ten moves building?
The sunk cost trap
Picture this: you've spent the last eight moves constructing a kingside attack. Your knight sits aggressively on h5, you've sacrificed a pawn, and your queen is poised to strike. Then your opponent finds a quiet defensive move — and suddenly, your attack is dead. The rational move is to regroup and shift strategy. Yet something resists.
This is the sunk cost effect — a well-documented phenomenon in behavioral economics and psychology. It describes our tendency to continue investing in a course of action simply because we have already committed resources to it, even when the rational choice is to stop. [1]
A famous real-world example is the Concorde supersonic jet. As early as the 1960s, British and French governments recognized that the aircraft was economically unviable — costs were spiraling, and commercial demand was far below projections. Yet both governments continued pouring billions into its development. Why? Because they had already spent so much. Abandoning the project felt psychologically unbearable, even as every new analysis confirmed it was the right call. The plane eventually flew for thirty years without covering its development costs, and the cognitive bias it so perfectly illustrated is now sometimes called the Concorde fallacy. [2]
Chess is a miniature Concorde, played out in minutes or hours. The moves you've already made feel like an investment — and your brain does not want to write them off.
The neural underpinnings of sunk cost behavior are still an active area of research, but current evidence suggests the involvement of regions such as the anterior cingulate cortex (ACC) — known to play a role in monitoring conflict between competing choices — as well as reward circuits that may encode expected value based on prior commitment rather than future outcome. [3] When you've committed to an attack, abandoning it doesn't just feel like a strategic retreat — it may register as something closer to a loss. The exact mechanisms remain debated, and translating findings from controlled experiments to the complexity of a chess game requires caution.
Mental flexibility as a skill
Strong chess players develop what we might call cognitive flexibility — the capacity to decouple current decisions from prior investment. This executive function is broadly associated with the prefrontal cortex (PFC), which is thought to play a role in overriding habitual or emotionally-driven responses in favor of deliberate reasoning.
In practice, this means deliberately resetting your evaluation: "If I arrived at this position fresh, with no memory of how we got here, what would I think of it?" By mentally treating your own previous moves as moves made by a stranger, you strip away the emotional ownership that fuels the sunk cost bias. It sounds simple. It is surprisingly hard to do under time pressure.
More broadly, EEG research on chess players offers some intriguing hints. Frontal theta oscillations — a signal associated with cognitive control and working memory — have been observed during demanding decision-making in expert players. [4] Whether this maps specifically onto moments of plan revision in chess remains an open question, and one I hope to explore further in future posts. What seems reasonable to say is that overriding a prior commitment is cognitively costly — and that this cost may be one that skilled players learn to manage over time.
What the chessboard reveals about the mind
Chess is a uniquely powerful lens for studying cognition precisely because it is structured, observable, and high-stakes enough to engage genuine emotion. The sunk cost effect and cognitive flexibility are not chess-specific phenomena — they appear in medical decisions, financial markets, engineering projects, and personal relationships. But the chessboard makes them visible move by move, in real time.
What I find most striking, as a neuro-engineer, is that the fight against your own biases is itself a measurable neural event — even if the full picture is far from settled. Your brain is not a passive observer of your decisions: it is an active participant, pulling you toward familiar patterns and resisting costly updates. Understanding even the rough outlines of that mechanism feels like a useful first step.
References
- Arkes, H. R., & Blumer, C. (1985). The psychology of sunk cost. Organizational Behavior and Human Decision Processes, 35(1), 124–140. DOI ↵
- Dawkins, R., & Carlisle, T. R. (1976). Parental investment, mate desertion and a fallacy. Nature, 262, 131–133. (Note: the "Concorde fallacy" label was popularized here, though the economic case itself is well documented in policy history.) DOI ↵
- Sweis, B. M., Abram, S. V., Schmidt, B. J., Pearson, J. M., & Zempel, J. M. (2018). Sensitivity to "sunk costs" in mice, rats, and humans. Science, 361(6396), 178–181. DOI ↵
- Wan, X., Nakatani, H., Ueno, K., Asamizuya, T., Cheng, K., & Tanaka, K. (2011). The neural basis of intuitive best next-move generation in board game experts. Science, 331(6015), 341–346. DOI ↵