I'd say my shut-in tendencies stem from me being the type of person who acts based upon the level of urgency of the situation I'm in, and can't really function if I'm in stagnant situation where I have nothing to react towards. In other words I feel much better geared towards dealing with situations where I need withstand an onslaught of things being thrown at me, then in situations that demand a high level of both initiative and creativity. I believe my reclusive tendencies originate from the fact that I'm quite poor at coming up with ideas. (Unless I'm in a situation where the objective task is to come up with ideas, such as posting ideas in an online forum such as this one) When I'm at home alone I simply don't have any ideas for stuff to do, which results in me just doing nothing and being a shut-in as a result.
I'm sure this is all strongly related towards introversion and weak and/or devalued Ne but I'm unsure whether any of this could be tied specifically to either Ne polr, Ne ignoring, or perhaps even Ne suggestive. As I said I think I'm decently able to come up with ideas when it's the topic for discussion, but when it comes to day to day life I'd definitely say I'm quite poor at seeing possibilities and alternatives to dig myself out of holes.