I tried to go to sleep last night without really being tired. I just closed my eyes and waited to see what would happen. As I laid there I started to feel strange, or better yet, awkward. Imagine that a few major muscles in your shoulder went numb then you try to move a piece on a chess board. You can still move your arm but just can't move it in any kind of skillful way. That is the kind of ineptness that I felt. Though nothing was numb and I wasn't trying to do anything specific.
It happens a few times a year so I like to experiment a with it a little bit when it does happen. And like all the other times I know when I open my eyes things are going to look different. It always seems to happen in very soft light. The full moon last night an a few LED's were sufficient.
When I opened my eyes I seemed to have lost all sense of proportion. I can see shapes but size doesn't seem to mean anything. As I fixate on one object, like my bookshelf, it feels as though my brain is testing out different possible sizes for it, thought none are any more valid than the others. So it erratically seems to be getting larger and smaller though always staying the same shape and in constant proportion to everything else.
From previous experimentation I knew that visualizations were hard in this state. So I closed my eyes and tried imagine what I would look like to somebody standing a few feet away. I couldn't do it. I tried to imagine what my house looked like from the outside and I got it but I couldn't hold the picture. As the picture became a little more stable I tried to imagine walking into my front door and moving around inside. As this became easier I noticed the feeling of ineptness started to lift. Then I opened my eyes and everything looked right again.
It's not a scary state. Normally I just turn on a light and give my head a shake to bring things back. This is the first time I got it to go through visualization... assuming that is what made it go. I like trying to figure out how it happens. My best guess to date is that in building a 3D model of your surroundings you use some stored information in conjunction with the visual information. But perhaps as part of the process of going to sleep these two functions separate and I try to build my models from purely visual cues. That would explain the proportion problem, but not the ineptness that comes before it. I guess I would like to know what happens but experimentation is fun too.