I have always found interesting that we thing as equivalent "different parts of the brain light up" and "good for the brain". I say this as someone who has an tiny knowledge of neuroscience, but wouldn't you want sometimes to have low brain activity, for certain things?

Having the brain making more connexions and using more resources to do the same thing could be seen, from one point of view, as waste ?

Not that I disagree with the article, of course. Test results speak for themselves, but for example, when I am writing stories, do I need to "better remember" them, or do I need to go faster through my first draft ? (3 years and counting at the moment...wish me luck !)