Working memory
Keep recent spatial positions available long enough to make the next comparison.
Working memory
N-back
Hold a short sequence in mind. Respond when the current position matches the position from N steps earlier.
About the N-back task
Compare the present with recent memory
In a spatial N-back exercise, one position appears at a time and you decide whether it matches the position shown N steps earlier. A 1-back round compares with the previous position; 2-back and 3-back require you to maintain and update a longer moving window.
The task is demanding because old positions must be released as new ones arrive. This version keeps the session to 20 rounds, uses a simple grid, and reports transparent accuracy information without presenting the result as an intelligence score or clinical assessment.
Continuous updating
Add each new position while allowing information outside the current window to fade.
Response control
Wait for a genuine match instead of pressing whenever a location merely feels familiar.
Practice well
Build accuracy before difficulty
Start with 1-back and quietly name or visualize each position. For 2-back, think of two alternating slots: compare the new square with the older slot, respond if needed, and then replace that slot. Use whichever mental representation feels least effortful.
Move up only after the lower level feels stable. One focused 20-round session is enough at first. Performance naturally changes with fatigue and distraction, so compare patterns across several sessions rather than drawing conclusions from a single score.
Common questions
About this exercise
What does the N in N-back mean?
N is the number of steps you look back. In 2-back, the current square is compared with the square shown two turns earlier.
When should I move from 1-back to 2-back?
Move up when you understand the update rhythm and can complete 1-back accurately without feeling rushed. Return to an easier level whenever needed.
Is this an IQ or memory test?
No. It is a practice exercise. A result is influenced by familiarity, sleep, attention, and the device you use, so it should not be interpreted diagnostically.