Diffuse-mode thinking is what happens when you relax your attention and just let your mind wander. This relaxation can allow different areas of the brain to hook up and return valuable insights. … Diffuse-mode insights often flow from preliminary thinking that’s been done in the focused mode.

When mastering a subject, our brains actually use different types of processing. Barbara Oakley explains in A Mind for Numbers: How to Excel at Math and Science (even if you flunked algebra) that our brain has two general modes of thinking – ‘focused’ and ‘diffuse’ – and both of these are valuable and required in the learning process .