If you are interested in dual n-back and working memory, check out this study:
No Evidence of Intelligence Improvement After Working Memory Training: A Randomized, Placebo-Controlled Study [PDF]
Numerous recent studies seem to provide evidence for the general intellectual benefits of working memory training. In reviews of the training literature, Shipstead, Redick, and Engle (2010, 2012) argued that the field should treat recent results with a critical eye. Many published working memory training studies suffer from design limitations (no-contact control groups, single measures of cognitive con-structs), mixed results (transfer of training gains to some tasks but not others, inconsistent transfer to the same tasks across studies), and lack of theoretical grounding (identifying the mechanisms responsible for observed transfer). The current study compared young adults who received 20 sessions of practice on an adaptive dualn-back program (working memory training group) or an adaptive visual search program (active placebo-control group) with a no-contact control group that received no practice. In addition, all subjects completed pretest, midtest, and posttest sessions comprising multiple measures of fluid intelli-gence, multitasking, working memory capacity, crystallized intelligence, and perceptual speed. Despite improvements on both the dual n-back and visual search tasks with practice, and despite a high level of statistical power, there was no positive transfer to any of the cognitive ability tests. We discuss these results in the context of previous working memory training research and address issues for future working memory training studies.
Here’s another article:
Review of working memory training programs finds no broader benefit
A recent review of the research to date has, sadly, concluded that the benefits of working memory training programs are limited. But this is not to say there are no benefits.For a start, the meta-analysis (analyzing data across studies) found that working memory training produced large immediate benefits for verbal working memory. These benefits were greatest for children below the age of 10.
These benefits, however, were not maintained long-term (at an average of 9 months after training, there were no significant benefits) — although benefits were found in one study in which the verbal working memory task was very similar to the training task (indicating that the specific skill practiced did maintain some improvement long-term).
Visuospatial working memory also showed immediate benefits, and these did not vary across age groups. One factor that did make a difference was type of training: the CogMed training program produced greater improvement than the researcher-developed programs (the studies included 7 that used CogMed, 2 that used Jungle Memory, 2 Cognifit, 4 n-back, 1 Memory Booster, and 7 researcher-developed programs).
Interestingly, visuospatial working memory did show some long-term benefits, although it should be noted that the average follow-up was distinctly shorter than that for verbal working memory tasks (an average of 5 months post-training).
What do you think?