In the previous Chapter, the active processes that happen in the brain in the different stages of memory consolidation during sleep have been discussed. Note also how a recent study[28] discovered that the brain is selective with the memories that it consolidates during the Slow Wave Sleep stage.
As previously mentioned, this preference is based on what the brain, during the conscious stage, considers as “relevant” and that information that has to do with “future plans”. In simple words, what you have been paying attention to because you consider it as important while you’re learning something might have a chance of being consolidated as you sleep.
Not all memories will be consolidated and transferred to long-term storage. But if during wakefulness, you consider these memories as germane, the brain will work to target these memories and reactivate them in the Slow Wave Sleep stage. This is where the significance of focusing ability comes in. While you are learning something, it will work best if you just pay attention and train your mind to focus into what you intend to know and store in your memory.