I too have had this happen. Usually I get the squiggly lines, or ones that form themselves into a shaft, like endles square inside square, but those were in childhood. I occassionally do get visions or pictures, but they rarely move
or talk, if they do I assume I'm starting a dream.
What they mean is perhaps u r a lucid dreamer? Whatever u want them to mean
would be my guess. Do you think/believe this may be a type of projection
either into another earth local, or perhaps another plane, astral/spiritual?
Interesting stuff, keep us posted.