Now that book has been around a long time, and draws on Sperry's original research from the 1960's, so it refers to these mental processes in the original "left-brain/right-brain" parlance, which is not technically accurate: these processes are not strictly hemispherically divided. But the observation of interference between these modes remains valid, as we continue to better understand the underlying mechanisms.
So I came up with naming these mental processes "linear-mode" and "rich-mode", which had the advantage of retaining the L-mode and R-mode abbreviations, while moving away from the misleadingly simplistic right/left brain, hemispheric duality.
And some people get really hung up on that. But the fact is that no, we really don't have a firm idea of how the brain actually works. It's a complicated, self-modifying mess. We've got a good start on it, and we're learning and researching more all the time. But clearly we can take advantage of what we know of the brain already, even as the explanations become more refined and more robust as we go along.
Henri Poincaré's method works well for me: push the problem out of your foreground mind, and just "hold it lightly." Then go for a walk, etc. That's when insights and breakthroughs come to me.
Having authored nine books and tons of programming code over the years, I have to say it really does work ;)
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