There is a long-standing debate in cognitive science about whether working memory training transfers to general cognitive ability. The institution does not claim it does. What I can report from personal experience:
- My n-back score has improved from 4-back to reliable 6-back over five months.
- My working memory subscale on the Diagnostic has improved by 11 points.
- My reasoning subscale has improved by 4 points over the same period, without dedicated reasoning practice.
Correlation, not causation. The 4-point reasoning gain could be explained by improved sustained attention, better sleep, or simply more practice with the Diagnostic format. But the working memory subscale gain is real and directly attributable to training volume.
The transfer debate is academic. The subscale improvement is not.