Writing is not typing. It's thinking, and preferably thinking using both sides of your brain, both the verbal, logical left, and the creative, intuitive right brain. The two halves of your brain are so different that you're basically two completely different people.
In Writing the Natural Way (a must-read, if you care about your writing skills), Gabriele Rico calls the two halves of your brain your Sign and Design minds.
I've been going back to using a pen and notebook as a FIRST choice before I write. This is because in a blank, unlined notebook, I can create a cluster and vignette (see Rico), and use the cluster as a springboard for a first draft. I do use Inspiration and Mind Manager, which are mind mapping applications, but I've found that nothing replaces a hand-drawn cluster. Why? I have no idea. :-) It works for me, so I don’t care to question the results. I find that if I'm using a pen and paper, I get deeper associations, than I do using a computer program.
For me, Inspiration and Mind Manager work more as structuring tools, than as left and right brain thinking tools. You may get different results. :-)
Try using a pen and paper. Jack Vinson's useful item "Thinking while note taking" says:
Writing, on the other hand, allows me to make more jumps and smash thoughts together even when they are not discussed in the same sentence. You might talk about X-Y-Z-A-B-C-Y, and I can lump the Y's together by simply smashing some text into the margin. Or I can draw lines and arrows and conceptually group things with circles and squares.
There seems to be a movement back to using pen and paper (yes, I'm a fountain pen nut). My feeling is that many of us are discovering that we need both halves of our brain, and pen and paper gives us best access to the right brain.