I think different people experience disembodied spirits in different ways, anyway. I don't see or hear them (I don't want to see or hear them). But I am very aware of their presence. Seeing or hearing them would disturb me a lot (or feeling them jump on the bed, for that matter), but the way I am aware of them doesn't bother me at all. For me it's more of an inner sensing in that I can feel their energy, and communicate with it.

What I don't understand is, why, when people encounter such spirits, they don't try to help them move on. Moving on is what they need to do. They don't really want to be stuck here forever. It's very rewarding to help someone who is stuck to move on, and it's better for everyone if they do, unless they're where they are because they have some particular work to do in that location (I have encountered some for whom that was the case).