Dual n-back is a cognitive training task which exercises your working memory in a way that has been shown, in numerous peer-reviewed scientific studies, to have a significant positive effect on intelligence. The task is quite challenging, and it may take a little while for you to get the hang of it. To speed up your progress, we’ve put together a step-by-step guide that walks you through the process.
The Basics: A Visual Stimulus and an Auditory Stimulus
In dual n-back, you need to process and memorize a sequence of stimuli that are presented to you. It’s called dual n-back, because there are two stimuli: a visual one and an auditory one.
This is what the playfield looks like:
At each step of the task, you will be presented, simultaneously, with
- a square that’s positioned somewhere on the playfield (the visual stimulus) and
- the sound of a letter being read out to you (the auditory stimulus).
The goal is for you to try and
- memorize both (1) the position of the square and (2) the sound of the letter, and then to
- notice it when, in a specific subsequent step, the position and/or sound get repeated.
When the position gets repeated, you should tap the “Position” button. When the sound gets repeated, you need to tap the “Sound” button.
You need to match position and sound stimuli between a specific number of steps, which depends on your n-back level. At n=1, a.k.a. “1-back”, you need to go back by 1 step to retrieve the position and sound from your memory and check for a match. By contrast, at 3-back, for example, you need to compare stimuli that are 3 steps apart: You’ll be comparing the stimuli from step 4 against those from step 1, those from step 5 against those from step 2. Etcetera.
Getting Started: Playing Dual N-Back at Level 1
Let’s look at 1-back in more detail. Here’s how the first few steps in a round of dual n-back might look like:
At step 1, all you need to do is memorize the position of the square (top-left) and the sound of the letter (“H”). Easy.
Next, at step 2, you need to do two things.
- First, you need to compare the new stimuli against those from 1 step back. The square at step 2 (bottom-right) is shown in a different position from that of step 1 (top-left), and the letter that is getting read out (“G”) is also different from step 1 (“H”). Since there is neither a position match nor a sound match, you should refrain from tapping the “Position” or “Sound” buttons.
- Second, in addition to comparing the stimuli from step 2 against those from step 1, you need to memorize the stimuli from step 2 for the next step. This is what makes dual n-back so challenging: At any given step, you need to not only compare the new stimuli against those from a previous step, but also memorize the stimuli from the current step for a subsequent step.
At step 3, you’ll notice that the position of the square (bottom-right) matches the position of the square from step 2 (bottom-right as well), hence you tap the “Position” button. The sound (“W”) is different from step 2 (“G”), however, so you refrain from tapping the “Sound” button.
Taking it up One Notch: Playing 2-Back
Having played a few rounds of 1-back, you’ll eventually get the hang of it and progress toward the next level: 2-back. This is where your brain will start hurting. (Remember: No pain, no gain.)
In 2-back, you have to compare the new stimuli from the current step against the stimuli that were presented to you exactly 2 steps ago. By implication, you’ll have to carry the remembered positions and sounds in your memory for 2 steps.
Here’s how this might look like in practice:
Step 1 will feel familiar to you. As in 1-back, all you need to do is memorize the position of the square (top-right) and the sound of the letter (“T”). So far so good.
At step 2, you can remain in memorization mode: Simply try to imprint the position of the square (center-bottom) and the sound of the letter (“C”) into your memory. Note that, at this moment, you will be carrying two sets of stimuli in your memory.
- The position and sound from step 1.
- The position and sound from step 2.
At step 3, things get interesting. This being 2-back, you need to compare the newly presented stimuli against the stimuli from 2 steps back – i.e., against the stimuli from step 1. The new visual stimulus at step 3 is a square in the top-left corner, which doesn’t match the position from step 1 (top-right), hence you should refrain from tapping the “Position” button. The new auditory stimulus at step 3 (“T”), by contrast, matches the auditory stimulus from step 1 (“T” as well), hence you do need to tap the “Sound” button.
At the same time, you need to memorize the stimuli from step 3 in order to be able to assess potential matches 2 steps later, at step 5.
And then you just keep going. At step 4, you compare the newly presented stimuli against the ones you memorized from step 2, then carry these new stimuli in your memory until step 6. At step 5, you compare the new position and sound against those from step 3, all the while memorizing them for step 7. Etcetera.
What if, at step 3, the new visual stimulus had been a square in the bottom-center position instead? You might have been tempted to tap the “Position” button. After all, the bottom-center position would have felt vaguely familiar to you. But that would have been a mistake: The square had been flashed in the bottom-center position at step 2. But in 2-back, you always need to go back by exactly 2 steps — not by up to 2 steps. By implication, at step 3, you need to recall the stimuli from step 1. And at step 1, the squash had been flashed in a different position (top-right) from step 3.
The Sky Is the Limit: 3-Back and Beyond
Once you master 2-back, it’s time for 3-back. The logic remains the same: Now, instead of comparing newly presented stimuli against those that were presented 2 steps ago, you’ll need to go back by 3 steps. This means that, at any given moment during a round, you will be carrying 3 steps in your memory simultaneously.
Dual n-back gets exponentially harder whenever you move up a level. In line with the methodology used in scientific studies, a well-designed dual n-back app will automatically move you up and down the n-back levels such that you will be maximally challenged at every moment.
Remember that the goal is not to try and achieve the highest possible n-back level. This would only tempt you to apply mnemonic tricks, which reduce the strain on your working memory and thus undermine the very effects you are trying to achieve: an increase in intelligence. Instead, aim for feeling maximally challenged, exhausted, and frustrated: That’s when you will be growing fastest.
Ready to Try? Take the N-Back Challenge!
If you’re ready to give dual n-back a shot, check out our N-Back Challenge, available both on iOS and on Android. Our two founders – both PhDs, one with a focus on neuroscience, the other with a focus on higher education – have taken particular care to thoroughly align the app with the prevailing scientific research. This maximizes the probability that, upon completion of the program, you will actually experience the cognitive benefits demonstrated in the studies. In addition, upon designing the app, we have put a special emphasis on helping you actually keep at it for the full 20 sessions that it takes to finish the program. This is key, because dual n-back training demands quite a bit of motivation and self-discipline. (As we like to say: It’s no fun, but it works!) To that end, we have designed the app around a “20-Day Challenge,” with various reward mechanisms to keep you engaged, such as statistics that track your progress, comparisons of your performance against other learners, an opportunity to build up daily “streaks,” and more!