When to switch to tri / quad back?

[Alexander]

Hello. I am currently doing dual n-back. When should I switch to quad/tri back? My current n-back level is 4 ±1. 

[Iris O'Solomon]

Wait until you are n=9.

[Mister McBlubbercus]

It depends on your goals for N-Back training. 

If you want to increase working memory (WM) capacity, then sticking to Dual-N-Back and getting to higher levels will do just fine. 

However, if you seek to increase the "quality" or "resolution" of your current WM capacity (e.g. how many tiny details you can remember in every memory item), then Quad-N-Back will get you there over time.

Some quick math for the rationale:

1. Say you can do Quad-6-Back. According to most internet views, this means that you can hold 24 items of information in WM (6 times 4 = 24).

2. Let's say the average person's WM capacity is around 7 items (+/- 2 items per standard deviation).

3. This means that 7 items = 0 standard deviations from the mean. Therefore, 9 items = +1 SD, 11 items = +2 SD, 13 items = +3 SD, 15 items = +4 SD, 17 items = +5 SD, 19 items = +6 SD, etc.

4. We know that only 0.000000099% of data will fall at or above 6 SD from the mean. This is 1 in 1 billion.

5. summary: This means a person who can do Quad-6-Back is one of 8 people on earth have a WM capacity this large.

6. In my time, I've heard way more than 8 people on the internet claim Quad-N-Back levels above 6. A prominent Youtuber has even shown his 3-year progress towards Quad-8-Back.

7. conclusion: It is statistically impossible that Quad-N-Back at higher levels is increasing WM capacity that much. People are most probably training task-specific strategies at that point and not WM.

takeaway: 

If you want a quantity increase in WM, take Dual-N-Back as far up as you can go. Just avoid using strategies that merely increase N-Back level but decrease cognitive load on your WM.

If you want to make your existing working memory "high definition" (in the words of those who've done Quad-N-Back for years), then use Quad-N-Back for a long time.

Take care.

[Abc]

"If you want to make your existing working memory "high definition" (in the words of those who've done Quad-N-Back for years), then use Quad-N-Back for a long time."

Can you find back where you read that from? I've spent tens of hours reading this group and reddit comments and never came across this

[Steinbi]

Daniel, if that is his real name, used to lurk here some years ago and maybe still does, spoke in this forum about it: https://groups.google.com/g/brain-training/c/Ks25uho8k9Y/m/zysFORQOCwAJ

He also made a video about his experience of using QnB for a long time, mentioning he gained a "higher definition" of vision through the training. I've experienced something similar to a less degree where I was more attentive of my environment, as in I could take in more at the same time. This was after quite intense training for the last weeks. I could simply process more in my visible field, due to higher working memory capacity I believe. I think QnB especially intensifies this through its high load (spatial, color and image) on the visual working memory (BA 6/9) and sensory processing part of the brain (BA 40, parietal lobe).