Here's a bit of a story from my childhood that's related to this question.
(Sorry if this is too long but I wanted to explain what I mean.)
I grew up in Sweden in a family of Finnish immigrants. During summertime, when most people took their 4 weeks of vacation, my family would often visit the locality where my dad had grown up, in the Satakunta region.
This locality was about 7 miles from the nearest town and about 20 minute walk to the nearest neighbor. It had been more densely populated in the past but esp. since WW2 people had started moving to larger cities where most of the jobs were. The "farm" (more like a set of houses but no farming or horses for since a long time) where my dad grew up had a main house, two barns, and a separate small sauna building. The main building looked similar to the building to the left in this picture.
Usually when we visited this place, our relatives from other parts of Finland came also so that everyone's kids (my dad had like 6 siblings) could have a chance to be with each other. During these weeks everyone slept in the main house, and supposedly that is where unusual things had sometimes happened.
What I was told is that sometimes one of my uncles had woken up at night because he felt like something (invisible) had sat down on the couch he was sleeping on. At some other times supposedly someones cover had been yanked from off him. Or they had heard foot steps from the stairs leading to the attic, as if someone was coming down from the attic.
And then there was a story that supposedly had happened to my grandfather, on the day his friend had died. This friend had come to visit him and they had chatted for some time and when the friend had left, he had supposedly walked through a closed door and disappeared. Later on my grandfather had heard that that friend had actually died earlier that day.
My dad also told me that his grandfather's father was supposedly known as a male witch (or "warlock" I guess is the right term) although he seemed to have been more like a part-time such.
There were more paranormal stories like these although I never experienced much of anything during the times I visited the place.
(Just wanted to add that I do realize that some people believe these kinds of events are hoaxes, jokes, or are only "experienced" by people who have psychiatric problems, but I personally never felt that I had enough reason to doubt my uncles, aunts or dad who told me these things.)
What I wanted to ask is, do JWs have a belief about these kinds of things, and if so, what causes them? Are there lost souls that are trapped between heaven and hell, or is it something else?