When you're learning, what you want to do is study something. Study it hard by focusing intently. Then take a break or at least change your focus to something different for awhile. During this time of seeming relaxation, your brain's diffuse mode has a chance to work away in the background and help you out with your conceptual understanding. Your, your neural mortar in some sense has a chance to dry. If you don't do this, if instead, you learn by cramming, your knowledge base will look more like this, all in a jumble with everything confused, a poor foundation.
When you look at something that you really rather not do, it seems that you activate the areas of your brain associated with pain. Your brain, naturally enough, looks for a way to stop that negative stimulation by switching your attention to something else. But here's the trick. Researchers discovered that not long after people might start actually working out what they didn't like, that neurodiscomfort disappeared.