I had a month long hospitalization at the age of 35 and it felt like it solidified my need to introvertedly sense. I was extrovertedly sensing too much and had become very erratic and sort of locked into the lower functions or the functions of model B (Fi, Ne, & Te).
Some of the problem is that the type of work I usually do doesn't really support my primary or secondary functions. Therefore I feel like I have to sharpen other parts of the personality to fit in in a work environment that doesn't favor idealist energy.
Anyway - Introverted Sensing is developing my inner guardian. That guardian energy that I am so hungry for resonates within me and I was sort of raised by wolves so I experience this as a process of maturing, becoming more civilized, learning to balance and tame extroverted sensing.