This happens to me too! I would say that taking a break helps me a lot. Get up, go to a new part of your house or building, get a snack and some water, and maybe watch a funny YouTube video. Allowing yourself to take a break sometimes let’s you seal in the information you’ve already gained.
Also sometimes taking a power nap will help as well :)
I'll try this method out. However I still feel the hard rock in my brain