3000 word artical you can definately activated straight away, right after photoreading.
Mind maps are for key words to help you bring back the memory of the ideas. Just like the name of your home town brings back many thoughts and ideas about that town. So what you are doing when you write and draw on a mind map is creating a link to the ideas that are important to you from a book or article.
If you want to remember things better you need to start by trusting you have a good memory and creating ways to remember what you want to remember.
Linking new ideas to old ones, mind maps drawn with a 'having fun' frame of mind (draw them funny if it helps), playing games to test how well you are remembering something and using various memory tricks. I suggest you try a search of the world wide web for memory tricks. You find some ideas that you might like better than others.
Alex