01
1234
Shape
See a shape
Treat the lit blocks as corners of a letter or shape, a Z, a triangle, an arrow. One shape is far easier to hold than five separate spots.
In your head“a Z, left to right”
TWO SYSTEMS, NOT ONE
Your mind keeps a notepad and a sketchpad
In Baddeley and Hitch's model of working memory, words and numbers go through a phonological loop, while places and shapes use a separate visuospatial sketchpad. Digit Span trains the first. Corsi trains the second.
Phonological loop
Holds sounds, digits, words, a phone number you repeat under your breath.
4827
Visuospatial sketchpad
Holds where things are, a route, the layout of a room, where you left your keys.
Eight ways to hold a longer path
Blocks on their own are hard to remember; the path they make is easy. Try one per round, then keep the ones that work for you.
02
1234
Gaze
Trace with your eyes
Follow the path with your gaze as it lights up, then replay the same eye movement when you tap. Your eyes rehearse the route for you.
In your headlook → look → look → tap
03
12345
Group
Split it in two
Remember a long path as two short ones: the first three blocks, then the rest. Two small shapes beat one tangled line.
In your head[1 2 3] + [4 5]
04
1234
Words
Name the moves
Label each jump with a direction, up, right, down-left. A few words back up the picture if it starts to fade.
In your head“up, right, down-left”
05
123
Words
Imagine a grid
Lay an imaginary 3×3 grid over the board and give each block a cell: top-left, centre, bottom-right. Positions become names.
In your head“top-left, centre, bottom-right”
06
123
Shape
Use landmarks
Notice blocks that sit near a corner, an edge or right next to another block. Anchoring the path to landmarks stops it drifting.
In your head“corner, then the pair”
07
1234
Gaze
Shadow with a finger
Move a fingertip slightly along the path as it plays, without touching the screen. The movement gives your memory a second copy.
In your headtiny finger path, then tap
08
54321
Reverse
Rewind the film
For backwards, don’t rebuild the path from scratch. Hold it as one movement, then play that movement in rewind from the last block.
In your head5 → 4 → 3 → 2 → 1
A better session in three steps
How you practise matters as much as how long. Try this shape for each session.
1Warm up forwards
Play one forwards round to find today's level. Your span shifts a little with sleep and focus.
≈1 min2Pick one method
Use a single strategy from above for the whole round. Mixing methods mid-path usually breaks the chain.
≈1 min3Finish backwards
End with a backwards round. Reversing a path makes you hold and rework it, the hardest, most useful part.
≈1 minINSIDE YOUR BRAIN
Which parts of your brain Corsi Blocks uses
Remembering where leans on the right side of the brain, the mirror image of Digit Span. A network running from the back of the brain to the front maps the blocks, holds the order and moves your attention along the path.
1
Based on Gray's Anatomy, fig. 728 (public domain)
1Posterior parietal cortex2Frontal eye fields3Dorsolateral prefrontal cortex4Hippocampus
Dashed = deep inside the brain, not on the surface
Posterior parietal cortex
Parietal lobeBoth, right-leaningIts job
Builds a map of where things are around you.
In this game
Stores the position of each block as it lights up.
Frontal eye fields
Frontal lobeBoth sidesIts job
Moves your eyes and shifts your attention from place to place.
In this game
Traces the path with your gaze, why following it with your eyes helps.
Dorsolateral prefrontal cortex
Frontal lobeRight-leaningIts job
Keeps a sequence in order and works on it.
In this game
Holds the order of the path and reverses it in backwards mode.
Hippocampus
Temporal lobeRight sideIts job
Learns layouts and routes so they last longer than a few seconds.
In this game
Corsi found people with right temporal lobe removals struggled to learn a repeated block path.
CONTROL
Frontal areas steer
The prefrontal cortex and frontal eye fields keep the order and move your attention along the route.
STORAGE
Parietal areas hold
The parietal cortex keeps the map of block positions active while you tap.
WITH PRACTICE
The network gets more efficient
After weeks of working memory training, imaging studies have found increased activity in prefrontal and parietal regions.
Brain science sources
- Smith, E. E. & Jonides, J. (1999). Storage and executive processes in the frontal lobes. Science, 283, 1657–1661.
- Corsi, P. M. (1972). Human memory and the medial temporal region of the brain. Doctoral thesis, McGill University.
- Awh, E. & Jonides, J. (2001). Overlapping mechanisms of attention and spatial working memory. Trends in Cognitive Sciences, 5, 119–126.
- Olesen, P. J., Westerberg, H. & Klingberg, T. (2004). Increased prefrontal and parietal activity after training of working memory. Nature Neuroscience, 7, 75–79.
1972
Nine wooden blocks on a board
Philip Corsi designed the test for his doctoral thesis at McGill University, working in Brenda Milner's lab. The examiner tapped wooden blocks on a board, and the patient tapped them back in order.
It showed that damage on the right side of the brain hurt memory for places more than memory for words. Clinics and labs still use it today, often on a screen like this one.
SourcesCorsi, P. M. (1972). Human memory and the medial temporal region of the brain. Doctoral thesis, McGill University.Milner, B. (1971). Interhemispheric differences in the localization of psychological processes in man. British Medical Bulletin.Baddeley, A. D. & Hitch, G. (1974). Working memory. Psychology of Learning and Motivation, 8.Kessels, R. P. C. et al. (2000). The Corsi Block-Tapping Task: standardization and normative data. Applied Neuropsychology.
WHAT THIS GAME TRAINS
Remembering a path in space
Blocks light up in sequence and you repeat the route. Since 1972 it's been the standard test of visuospatial span: the spatial partner of digit span.
corestrongsomelight
coreSpatial working memoryHolding a sequence of locations.
strongSequencingKeeping the order right, not just the places.
someVisual attentionFollowing each flash as it happens.
someMental rehearsalReplaying the path in your head.
THE SAME SKILL, ELSEWHERE
Three places this skill turns up
Each one leans on a different part of what the game trains.