Wednesday, July 27, 2011

Flat screen

I read in the Internet how people who hadn't had but later acquired binocular vision are describing what lack of binocular vision feels like, by sentences like things stacked on top of each other, indiscernible mess of objects, etc.  I couldn't recall having any such experiences, yet my vision and vision perception has changed so much in the last month I wasn't sure about anything.

So I tried, consciously, to switch to an entirely flat perception, and just to project everything onto a flat screen. At first it didn't quite work - light, shade, empty spaces, movement didn't want to fit on a screen. However, after a minute or so I succeeded. This was very impressive, and didn't feel normal for me.

The carpet became like a vertical wall or a background. People standing further away became literally smaller, and were arranged as cards on a table. I believe I could still feel a change of muscle tension in the eyes as I looked at objects farther from me and closer to me. It was difficult to have a sense that one person was the same person all the time, as people had different size depending on where they were on the carpet.

At the point when the effect of 2-dimensionality was the strongest, I saw a woman who came and front and, as it seemed at that moment, above me. She dropped something on the floor, and as this object was flying down, I expected it would fall near my feet, since it was dropped "directly above" my feet, and was moving down. Yet it stopped at a point somewhat above my feet, where apparently it met the floor, and she leaned down to pick it up. Then, to switch back to what is my default mode, I just had to look at some empty space suspended in the air, in an appropriate location where I can notice it.

This difference doesn't even seem to depend on whether I am using one eye or both. Rather, it should be the visual cortex interpreting things in different ways. Even when my eyes are misaligned, I don't usually see such a flat screen as I experienced in this case. It seems that to see a flat screen, the visual cortex needs to (a) suppress one eye, and (b) disengage from the past experiences where it combined input from both eyes, including the experiences of seeing an object with one eye and the background with the other eye, fusing the background but seeing two copies of the object, and countless other combinations. There is something about the patters of light and shade that creates a feeling of empty space if both eyes are perceiving them, even if incoherently, and to see a flat screen one needs to somehow disengage from these pattern of light and shade, to just ignore them as a blur.

No comments:

Post a Comment