Far transfer effects of executive working memory training on cognitive flexibility

[Steinbi]

Here is an interesting recent article from I found on the relation between Executive WM training and cognitive flexibility, unfortunately I don't have access to the full paper but its premise is interesting:

"The near and far transfer effects of Working Memory (WM) training have yielded discrepant findings while there is no literature on the effects of Executive Working Memory (EWM) training. The present study aimed to investigate the far transfer effects of EWM on cognitive flexibility. Community participants (n = 144) were allocated into a fully-, a partially-trained or a control group. At a baseline assessment, all groups were administered the Wisconsin Card Sorting test and Letter-Number Sequencing (LNS). Following this and for six consecutive days, the fully-trained group were administered the complete LNS, the partially-trained group were administered the LNS up to the three-digit strings while the control group had no involvement in the study. Upon completion of training, all groups were administered the Intra/Extra-Dimensional Shift task (ID/ED). The control group (a) made more errors and completed fewer stages compared with the fully-trained group and (b) had increased response latency and required more trials to complete the ID/ED compared to both the partially- and fully-trained groups. In the total sample, (a) the lack of EWM training was associated with more total errors, trials required to complete the ID/ED, extradimensional-shift errors and prolonged response latency and (b) extended short-term EWM training was associated with more completed stages in the ID/ED. The findings support the far transfer effects of EWM training on cognitive flexibility and are in agreement with studies on WM training. Although preliminary, they hold promise for the enhancement of early intervention programs in populations with cognitive impairments."

I didn't really know what they mean by Executive Working Memory (EWM), or how that could be different to normal Working Memory so I looked it up. There seems to be some distinction between executive and short-term working memory in the research discussions. From my research into the literature, it seems also that n-back is pretty intense on brain areas responsible for executive functions so I would assume this would overlap somehow. 

This article mentions something more about EWM:

"Working memory has been described as a limited-capacity information processing system comprised of interdependent processes related to the executive control of attention (the central executive) and the active maintenance of short-term memory. Research suggests that the ‘capacity’ of the working memory system can be partitioned into separate capacities for the central executive (EWM capacity) and the scope of attention or short-term memory capacity. We focus here on the capacity of the ‘central executive’ component (i.e., EWM), which is common to all models of the working memory system, because its function is most critical for the adaptive self-regulation and decision-making and the deliberative process during decision-making in particular. EWM capacity is thought to reflect the ability to control attention associated with the capacity to direct and shift attention, and resist distraction, while encoding / updating, maintaining, and retrieving information from long and short-term memory buffers, a process which we maintain is critical during the decision-making deliberation process. EWM capacity is typically assessed using complex span tasks that include a dual task component."

It would thus seem to me that according to this highlighted text of the quote above that dual n-back training would be exactly providing the effect of training the ability to control attention and shift/direct capacity for memory updating and retrieving, in essence exactly the task of the executive function.

Cognitive flexibility is itself according to Wikipedia defined as:

"Cognitive flexibility has been more broadly described as the ability to adjust one's thinking from old situations to new situations as well as the ability to overcome responses or thinking that have become habitual and adapt to new situations. As such, if one is able to overcome previously held beliefs or habits (when it is required for new situations) then they would be considered cognitively flexible. Lastly, the ability to simultaneously consider two aspects of an object, idea, or situation at one point in time refers to cognitive flexibility. According to this definition, when sorting cards based on specific rules, children are considered cognitively flexible if they can sort cards based on the color of the objects and type of objects on the card simultaneously. Similarly, cognitive flexibility has been defined as having the understanding and awareness of all possible options and alternatives simultaneously within any given situation."

Furthermore, "Research has suggested that cognitive flexibility is related to other cognitive abilities, such as fluid intelligence, reading fluency, and reading comprehension."

So the conclusion, in my opinion, is that dual- or higher modal n-back modes is training cognitive flexibility and I would be interested to see any further research results on that theory. Any thoughts on this connection?

[Working Memory]

Thanks for the share. I'm willing to bet the combination of DnB/QnB and meditation covers most aspects of executive functioning.

The only thing that it probably leaves out is interference control, which can be added to some extent in DnB by changing the settings. Also, I always wondered if adding random distractors you are supposed to forget would help this in DnB. For example, adding a randomly added other visual cue in one of the blocks and an accompanying word or number etc. that is not supposed to be memorized. For example if using just DnB use a different colored block or a diamond or whatever instead for the red herring stimulus and a number instead of a letter, once again randomly interjected. 

The other question is whether DnB helps with lots of manipulation that reflects skills like reverse digit span or even more complex manipulation tasks. DnB seems to most help with capacity, updating and general attention. QnB seems to help with speed and visualization/visual attention skills. 

Of course, I've also read about how working memory has a correlation with 'second memory', short term memory and retrieving long term memories. When there are interconnected parts of the brain that associate with working memory, I've wondered if training the entire string of connections is better than training only the key working memory aspects alone. 

I can only posit that adding in short lists to remember for short term memory or somewhat recent reading comprehension and perhaps recalling events/information from the past while doing DnB suffice for this. 

In the end I still think meditation/DnB/QnB is the best we've got as is. Could DnB/QnB be enhanced? I think so.

[M A]

Hey I have also seen the initial article you linked and am interested in integrating executive working memory training into my practice. In the article the task they used to train EWM was just the Letter Number Sequencing task from the WAIS-IV. Ikokusovereighty has a free computerized version of the task he shared to measure working memory capacity. I'm pretty sure his version of the task only measures visual working memory because there is no audio. I think an audio version of the task would be nice because I'm pretty sure the LNS is done verbally during the WAIS (proctor recites sequence, subject responds verbally). I wonder if anyone on this group can make or find an audio version of the task and share it?

[M A]

Okay I found the demo versions of the Millisecond Sciences LNS Test:

Auditory

Visual

[Steinbi]

Thanks M A for finding and sharing this.

I think that the different features in the Brainworkshop application are more than enough to hit the executive working memory demands. As one threads on this forum from 2010 points out (link), executive functions of the brain seem to be being trained when doing "breadth" type of n-back modes, i.e. higher modal n-back modes. This thread mentions specifically PNB or pentuble n-back which stresses your working memory especially due to its dual sound mode. I've been trying this out now for the last days and actually feel a bit light headed after a session, kind of like in the early stages of discovering DNB. I cannot sustain any strategy while doing this and just have to deal with the onslaught of stimuli. I think this type of n-back is excellent for training EWM as its stressing the "executive" part of your brain which assigns resources to where to focus and sort your internal STM. I really cannot imagine how it feels/cognitive benefits when your brain has optimized to playing on higher n-levels of PNB, perhaps if anyone who has experience in that please share.

Similar to what A.Four.Sigma experienced, since I've been getting stuck on D5B/D6B for a month now, I'm going to try PNB now for a month to see how it influences my thinking / perception. I feel the sustained attention and focus benefits coming from N=5,6,7 is not really proving to be of such a benefit with an already strong focus/attention.