The study
In 2026, researchers from the University of Leicester and Liverpool John Moores University published a systematic review in Frontiers in Neuroimaging: every available study that scanned people’s brains while they solved sudoku. Six neuroimaging studies qualified — five using functional MRI (fMRI) and one using functional near-infrared spectroscopy (fNIRS), which measures activity at the surface of the brain under more natural conditions.
What it found
Across the studies, sudoku solving consistently engaged the brain’s frontoparietal network — the system behind deliberate, goal-directed thinking:
- The dorsolateral prefrontal cortex, behind the forehead, associated with executive control: planning, decision-making and working memory — holding several pieces of information in mind and manipulating them.
- Parietal regions, associated with visuospatial working memory: reading spatial relationships and patterns in a grid.
- The anterior cingulate cortex, associated with performance monitoring and cognitive control: noticing errors and adjusting.
The fNIRS study also found increased prefrontal activity while people solved sudoku in more everyday conditions.
What it doesn’t claim
The authors are careful, and so are we. Six studies is a small evidence base, and the studies differ from one another, so the review does not establish that sudoku improves intelligence, grades or memory. Its conclusion is more modest: sudoku reliably engages executive-control systems, which makes it a promising task for studying executive function and self-regulation. Whether regular play strengthens those abilities over time is still an open question.
Where NOTE-KU fits
NOTE-KU doesn’t promise more than the science does. What it does is make the thinking that sudoku engages explicit and structured:
| Phase | What you’re doing |
|---|---|
| Notation Pass | Holding several row, column and box constraints in mind for one digit across the board. |
| Elimination & Iteration | Tracking consequences, catching contradictions, adjusting your map. |
| Final Pass | Finishing the preparation before acting — patience and planning. |
| Temp Mode | Reasoning about your own uncertainty: forming a hypothesis and testing it. |
It’s also screen time of a particular kind: active, quiet and self-paced, with no chat, no account and no personal information requested. For a young learner, the 6×6 Mini is a gentle place to start.
Source
Williams, M.J., Williamson, E.J., & Brooks, S.J. (2026). Neural correlates of Sudoku play: a systematic review of brain imaging studies. Frontiers in Neuroimaging, 5, 1756394. doi.org/10.3389/fnimg.2026.1756394
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