This, applies more generally than to anosognosia alone, and was very illuminating, thank you !

So, provided that as we grow, some parts of our brain, mind, change, then this upsets the balance of our mind as a whole.

Let's say someone relied on his intuition for years, and consistently observed it correlated well with reality. That person would have had a very good reason to more and more rely on that intuition, and uses its output unquestioningly, automatically to fuel other parts of his mind.

In such a person's mind, one of the central gears would be that intuition. The whole machine would eventually depend upon it, and to remove intuition would mean, at best, that years of training and fine-tuning that rational machine would be lost; and a new way of thinking would have to be reached, trained again; most people wouldn't even realize that, let alone be bold enough to admit it and start back from scratch.

And so some years later, the black-boxed process of intuition starts to deviate from correctly predicting reality for that person. And the whole rational machine carries on using it, because that gear just became too well established, and the whole machine lost its fluidity as it specialized in exploiting that easily available mental ressource.

Substitute emotions, drives for intuition, and that may work in the same way too. And so from being a well calibrated rationalist, you start deviating, slowly losing your mind, getting it wrong more and more often when you get an idea, or try to predict an action, or decide what would be to your best advantage, never realizing that one of the once dependable gears in your mind had slowly been worn away.