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MEMORY · DIGIT SPAN

How Short-Term Memory Handles Number Sequences

A sequence of digits looks like a pure storage test, but performance depends on attention, order memory, rehearsal and strategy. The number you remember is only the surface of the task.

What this isAn original EgoTools explainer
What this is notMedical or diagnostic advice
MethodClaims kept narrower than the measurement

The task is temporary ordered recall

A typical number-span game presents a sequence, removes it and asks you to reproduce the digits in order. Remembering the set of digits is not enough: the sequence itself matters.

Chunking changes the effective units

“1 9 9 8 2 0 2 6” can be remembered as eight isolated digits or as two familiar year-like chunks. The physical input is the same, but the mental representation is different. That is why strategies can increase apparent span.

Attention failure can look like memory failure

If your attention drifts during presentation, the sequence may never be encoded cleanly. A single poor attempt therefore cannot distinguish limited storage from distraction.

Why researchers moved beyond the old ‘seven plus or minus two’ slogan

George Miller’s famous 1956 paper made “seven plus or minus two” culturally popular, but modern working-memory research emphasizes that capacity depends strongly on the material, chunking and task design. Nelson Cowan, for example, argued for a smaller core capacity under conditions that limit chunking and rehearsal.

What a browser digit game is good for

What it cannot tell you

It cannot diagnose memory disorders, measure all forms of memory or produce a standardized IQ score. Episodic memory, long-term learning, spatial memory and skill learning are different constructs.

Try it yourself

Use the explanation above, then run the tool and compare your own repeated results.

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