Dual N-Back · Guides
How long and how often to train dual n-back: what the studies actually did
Session lengths and frequencies used in dual n-back research, what the evidence shows about transfer, and how to set realistic expectations.
In this guide15
Start with a repeatable routine
A useful schedule specifies when you will practise and which settings you will keep comparable. Its purpose is to organise practice and make your record easier to interpret. It is not a scientifically established prescription for increasing intelligence.
What the original study did
In the 2008 study by Jaeggi and colleagues, four groups trained on a dual n-back task for 8, 12, 17 or 19 sessions, every weekday and not at weekends, for about 25 minutes a day. After every block, the level of n went up by one, went down by one or stayed the same, depending on the mistakes made. The groups that trained longer showed larger gains on the matrix-reasoning tests the authors used, while the comparison groups took the same tests without any training. The study was not designed to find an optimal schedule: the four trained groups followed the same rhythm, and the key difference between them was the number of sessions.
| Setting | What the study did |
|---|---|
| Participants | 70 healthy young adults: 35 trained, of whom 34 completed the training, and 35 in comparison groups without training |
| Training days | 8, 12, 17 or 19, depending on the group; every weekday, not at weekends |
| One day’s session | 20 blocks of 20 + n trials, about 25 minutes |
| Pace | One trial every 3 s: a square on screen for 0.5 s, then 2.5 s before the next |
| Stimuli | A square in one of eight positions and one of eight consonants through headphones |
| Targets per block | 6 visual and 6 auditory: 4 in one stream only, 2 in both at once |
| Level changes | After each block: n + 1 with fewer than 3 mistakes per stream, n − 1 with more than 5 mistakes (per stream or in total: the paper does not say), otherwise unchanged |
| Outcome tests | Matrix reasoning: Raven’s Advanced Progressive Matrices for the 8-session group, a short version of the BOMAT for the others |
What later research found
The picture became more complicated. Redick and colleagues in 2013 used an active control group and found no improvement in fluid intelligence after n-back training. Meta-analyses since have disagreed with each other, and Soveri and colleagues in 2017 found clear improvement on n-back tasks themselves, some on closely related tasks, and little beyond. In practice that means no study can tell you the schedule that will make you smarter, because that outcome has not been reliably demonstrated in the first place.
What practice can and cannot show
Practice can improve performance on the trained task, but the size and pace of improvement differ between people. A schedule does not guarantee better grades, workplace performance or everyday memory. Read the evidence guide before treating an exercise result as a broader benefit.
Spacing is a useful idea, not a proven n-back dose
Research on distributed practice supports spacing for many learning tasks. It does not establish that fifteen minutes on five days is the optimal dual n-back schedule, or superior to every alternative. Use manageable blocks to organise practice and record what you actually did.
An optional starting example
You could plan one short block on three days this week, using the same task and number of rounds. This is an organisational example, not a tested optimum. Review whether you understood the rule and could finish comfortably before increasing the duration or level.
Dual N-Back settings on iPhone: audio, feedback and levelsWhen a session feels too long
If you are tired, distracted or repeatedly losing the comparison rule, pause or stop. A longer session is not automatically more useful. Record the interruption rather than deleting an inconvenient result. The point at which concentration becomes difficult varies; this guide sets no universal time limit.
Keep the conditions visible
Sleep, interruptions and time of day can influence performance, but a single score cannot identify the cause of a change. Note unusual conditions and compare sessions conducted in similar circumstances. Do not use a low result to diagnose fatigue or a health problem.
Choose a level you can interpret
Keep learning the rule separate from testing a harder level. If you change N, label the session accordingly. Implementations differ: some adapt difficulty, while this app also uses selected levels and progression locks. A higher N with different settings is not directly comparable with your earlier score.
Structure one session simply
Before starting, choose the mode, N, number of rounds and feedback setting. If you do an easier warm-up, record it separately. After the block, read the result and take a break if needed. Repeat only if you want to practise again; there is no requirement to accumulate a particular number of blocks.
Learn 2-back with the interactive tutorial, then playChange one setting at a time
Changing one setting makes the next observation easier to interpret. Record the date and the setting changed, and keep separate groups of comparable results. A fixed two-week interval is not a scientific requirement; choose a review rhythm that gives you enough observations without forcing practice.
Do I need to practise every day?
No specific daily schedule is established as necessary for everyone. A missed day does not need to be compensated with a long session. After a longer break, check the rule and controls before comparing your results. The time needed to regain familiarity varies.
Ten dual n-back mistakes that quietly stall your progressReview several comparable results
Keep both disappointing and strong results. Look at sessions with the same mode, N, round count and scoring convention. A personal best is one observation; it does not describe your usual performance. A trend in the exercise also does not demonstrate a change in intelligence.
When to pause or change the plan
Pause if the activity is unpleasant or you are no longer following the rule. If results plateau, first check settings and recurring errors. A plateau does not diagnose a limit in memory capacity. You may change the plan or stop practising; no score creates an obligation to continue.
A one-week plan to adapt
Choose three convenient days. On each day, practise a short block at a level whose rule you understand, and record mode, N, rounds, feedback and result. At the end of the week, review the conditions and one recurring error. Decide whether to keep the plan or change one setting. This is an example, not a promise of results.
Questions
How often should you train dual n-back?
You could plan one short block on three days this week, using the same task and number of rounds. This is an organisational example, not a tested optimum. Review whether you understood the rule and could finish comfortably before increasing the duration or level.
How long should a dual n-back session be?
If you are tired, distracted or repeatedly losing the comparison rule, pause or stop. A longer session is not automatically more useful. Record the interruption rather than deleting an inconvenient result. The point at which concentration becomes difficult varies; this guide sets no universal time limit.
How many days a week did the original study use?
Five. Participants trained every weekday and not at weekends, for about 25 minutes a day, and the groups did 8, 12, 17 or 19 sessions in total. The study compared these amounts of training; it did not test whether another weekly rhythm works better.
Does taking a break set you back?
No specific daily schedule is established as necessary for everyone. A missed day does not need to be compensated with a long session. After a longer break, check the rule and controls before comparing your results. The time needed to regain familiarity varies.
When will I see results from dual n-back?
Practice can improve performance on the trained task, but the size and pace of improvement differ between people. A schedule does not guarantee better grades, workplace performance or everyday memory. Read the evidence guide before treating an exercise result as a broader benefit.
Further reading
- Jaeggi, Buschkuehl, Jonides & Perrig (2008), Improving fluid intelligence with training on working memory, PNAS
- Melby-Lervåg & Hulme (2013), Is working memory training effective? A meta-analytic review, Developmental Psychology
- Au et al. (2015), Improving fluid intelligence with training on working memory: a meta-analysis, Psychonomic Bulletin & Review
- Redick et al. (2013), No evidence of intelligence improvement after working memory training, Journal of Experimental Psychology: General
- Melby-Lervåg, Redick & Hulme (2016), Working memory training does not improve performance on measures of intelligence or other measures of “far transfer”, Perspectives on Psychological Science
- Cepeda et al. (2006), Distributed practice in verbal recall tasks: a review and quantitative synthesis, Psychological Bulletin
- Cepeda et al. (2008), Spacing effects in learning: a temporal ridgeline of optimal retention, Psychological Science
- Soveri et al. (2017), Working memory training revisited: a multi-level meta-analysis of n-back training studies, Psychonomic Bulletin & Review
Guides
How to play dual n-back: a clear first session
Understand position matches, sound matches and the meaning of N before your first dual n-back session.
Dual n-back scoring: formulas, examples and calculator
Understand hits, misses and false alarms in dual n-back. Compare scoring formulas with a worked example and an interactive calculator.
Does dual n-back training work? What the evidence actually says
An honest walk through the research on dual n-back: what improves, what does not, why the meta-analyses disagree, and how to train without fooling yourself.