Left Brain vs. Right Brain: How Abacus Activates Both Hemispheres

By Dr. Priya Venkatraman, Head of Pedagogy, AnzanPro

Ask any group of parents whether their child is "left-brained" or "right-brained" and you'll get confident answers. The left-brain/right-brain model is one of those ideas that escaped the laboratory and became cultural furniture — intuitive, quotable, and, in its popular form, substantially oversimplified.

But here is what is genuinely interesting: when we apply neuroscience to abacus training, the hemispheric distinction turns out to be real and important — not in the pop-psychology sense, but in a specific, measurable, meaningful way that has direct implications for how children learn.

The Left Brain / Right Brain Model: What's Accurate, What Isn't

The popular version of hemispheric theory — left brain = logical/analytical, right brain = creative/emotional — is a caricature. Both hemispheres participate in virtually every complex cognitive task. Language, for instance, involves the right hemisphere for prosody, metaphor, and contextual meaning, even though speech production is predominantly left-lateralised. Creativity requires the dorsolateral prefrontal cortex, which operates bilaterally.

What neuroscience does support is a more nuanced picture of hemispheric specialisation — tendencies, not monopolies:

The left hemisphere tends to dominate for sequential, symbolic, and language-based processing — breaking things into ordered steps, applying rules to symbols, and verbal reasoning
The right hemisphere tends to specialise in holistic, spatial, and pattern-based processing — perceiving wholes, recognising faces, manipulating objects in space, and processing visual scenes as unified structures

These are differences of emphasis, not exclusivity. But in the context of mathematics education, they matter enormously.

How Standard Arithmetic Activates the Left Hemisphere

Conventional mathematics instruction — as delivered in most schools around the world — is almost entirely left-hemisphere dominant in character.

Arithmetic is introduced through counting (sequential), number symbols (symbolic), rules (if the tens digit is greater than 9, carry one to the hundreds), and verbal repetition (reciting times tables). When researchers image the brains of children and adults doing standard arithmetic, they consistently see robust activation of left hemisphere regions: the angular gyrus (number symbol processing), Broca's area (verbal working memory), and the left inferior parietal cortex.

This is not a flaw in standard mathematics teaching — symbolic and sequential processing is part of what mathematics is. But it is a limitation. Standard instruction does not reliably engage the right hemisphere's spatial and holistic processing capacities, which are equally important for mathematical reasoning.

The consequence, for many children, is that mathematics remains a language task — a matter of applying verbal rules to symbols — rather than developing into the spatially grounded, intuitively quantitative thinking that characterises mathematical fluency.

How Abacus and Anzan Activate the Right Hemisphere

The soroban encodes number as spatial configuration. Each number from 0 to 9 has a unique, visually distinctive bead arrangement. Addition and subtraction are not rule-following operations — they are transformations of a visual image.

This spatial encoding naturally engages the right hemisphere's visuospatial processing systems:

The right parietal lobe handles the spatial relationships between beads and columns
The right occipital-temporal regions process the visual patterns of bead configurations
The right premotor cortex plans and executes the spatial movements of bead manipulation

Even in the early stages of soroban learning, neuroimaging shows greater bilateral activation compared to standard arithmetic — more right hemisphere involvement than untrained arithmetic would produce.

As training progresses to the mental abacus stage, this right hemisphere engagement intensifies. Holding a vivid, detailed visual image in working memory and updating it dynamically is a task that heavily recruits right hemisphere visuospatial networks.

Wang et al. (2019), in a well-controlled fMRI study published in Cerebral Cortex, found that expert abacus users showed significantly greater bilateral parietal activation during arithmetic than controls — and crucially, the degree of right hemisphere activation correlated with calculation speed and accuracy. The practitioners who had built the most robust right-hemisphere spatial representations were the fastest and most accurate calculators.

The Evidence for Bilateral Activation

The bilateral activation finding is one of the most consistent results in the abacus neuroscience literature.

Tanaka et al. (2002), in a study of Japanese abacus champions, found activation in both left and right hemispheres during mental calculation — contrasting sharply with the predominantly left-hemisphere pattern in non-practitioners. The right hemisphere activation was localised to visuospatial areas, consistent with the mental abacus hypothesis.

Li et al. (2013), studying children after two years of abacus training, found that the degree of bilateral activation increased progressively with level of expertise — suggesting that it is the training itself, not pre-existing ability, that drives hemispheric recruitment.

Critically, the bilateral activation pattern persisted even when abacus-trained subjects were asked to calculate using conventional methods — suggesting that training had permanently altered the cognitive strategy available to these individuals, not just the one they deployed when given a soroban.

Why Bilateral Activation Matters: Speed, Resilience, and Memory

The recruitment of both hemispheres is not merely neurologically interesting — it confers practical advantages.

Faster Processing

When information can be processed in parallel across both hemispheres, rather than serially through one, overall processing speed increases. The left hemisphere handles the symbolic/sequential aspects of a calculation while the right hemisphere simultaneously tracks the spatial state of the mental abacus. This parallel architecture is one reason why expert mental calculation is so strikingly fast.

More Resilient Memory

Memories encoded across multiple brain regions and modalities are more robust than those encoded in a single pathway. A calculation strategy that is simultaneously a spatial image, a motor programme, and a symbolic operation has multiple retrieval routes — it is harder to forget and more reliably accessed under stress or fatigue.

This is part of why abacus-trained children tend to maintain their computational fluency under examination pressure, while children whose arithmetic is purely verbal-procedural may have their performance more severely disrupted by anxiety.

Richer Cross-Domain Connectivity

Bilateral activation appears to facilitate stronger connections between the mathematical and spatial-creative processing networks — networks that in standard arithmetic training are largely disconnected. This may help explain why abacus practitioners frequently show advantages in spatial reasoning, geometry, and even creative problem-solving.

Implications for Creative Learning, Music, and Sport

The right hemisphere engagement developed through abacus training has implications that extend beyond mathematics.

Music: Musical reading and performance involve spatial pattern recognition, timing, and fine motor coordination — all right hemisphere associated functions. Several studies have noted that abacus-trained children transition into music learning with unusual ease, and it appears the overlapping neural infrastructure is at least part of the reason.

Sports: Spatial awareness, anticipatory movement, and the real-time adjustment of body position in space are fundamentally right hemisphere tasks. The enhanced visuospatial processing developed through abacus training may offer a cognitive advantage in sports that demand quick spatial judgment.

Art and Design: Visual thinking, pattern recognition, and the ability to hold and manipulate spatial images — all developed through abacus training — are foundational to artistic and design ability. Parents occasionally notice a parallel flourishing of visual creativity in children who progress through the abacus curriculum.

These are not guaranteed outcomes, and the research here is more speculative than the mathematics findings. But they point to abacus training as a development of whole-brain capacity, not narrowly "maths skills."

How the Soroban-to-Anzan Progression Drives Right-Hemisphere Engagement

The specific arc of abacus training — from physical soroban to internalised mental abacus to full Anzan — is not just a pedagogical progression. It is a neurological one.

The physical soroban engages the right hemisphere through motor and visual processing. As the mental abacus develops, the demand on right hemisphere visuospatial working memory intensifies. Flash anzan — processing a rapid sequence of numbers as spatial configurations — represents a peak right hemisphere training stimulus: the visual system must rapidly construct, update, and read a spatial image under extreme time pressure.

Each level of the progression recruits right hemisphere circuits more deeply and demands more bilateral coordination. The 10-level curriculum at AnzanPro is, among other things, a systematic programme for developing increasingly integrated bilateral brain function in the context of mathematical reasoning.

Practical Takeaway for Parents

The practical implication of all this is straightforward: if you want your child to develop genuinely flexible, powerful mathematical thinking — not just fast recall of memorised facts — you need to ensure their maths education engages both hemispheres, not just the left.

Standard school maths typically does not do this. Abacus training, done correctly and progressively, does.

Look for a programme that explicitly progresses from physical tool to mental calculation, includes visuospatial exercises (flash anzan, timed mental calculation), and is taught by instructors who understand the progression — not just the mechanics of bead movement, but the cognitive development journey the child is on.

The goal is not a child who is slightly better at arithmetic. The goal is a child whose mathematical thinking is architecturally richer, faster, and more resilient — because both hemispheres have been trained to work together on every problem they face.

Explore AnzanPro's hemisphere-engaging curriculum and find a centre in your city at anzanpro.com. Book a free trial class and see bilateral activation in action.