Try the chimp test
Young chimps beat college students at this: numbers appear on a grid, hide after your first click, and you finish the order from memory.
Tools used in this guide
The job
Based on the Kyoto University Ayumu experiments: numbered squares show briefly; clicking '1' hides the rest; you must then click 2, 3, 4… in order from memory alone.
Memorize the positions
Level 1 places 4 numbers on the 5×8 grid. Memorize where each sits before your first click — after that, only blank squares remain and the order is up to you.
Worked example
Clearing level 1 adds a square: 5 numbers, then 6. Around 9–10 squares is where most humans stall; Ayumu did 9 in a fraction of a second.
Where it stops
One mistake ends the run — there is no partial credit or strike system. Positions and numbering are random each round, so patterns can't be memorized between attempts.