How can my brain percieve things in the environment as stable, when they are moving around my retina?

Question

Constancy.. How does the brain keep the stable stable, keep it's facts straight so to speak, as it moves around..?

Answer 1

Mm. I learned a really interesting fact the other day. They did an experiment where they put a person's head in a clamp to keep the person's head still. Then they show them a page of text on a screen. As the person reads the text, and go back and read it again, and skip around the page to read random sentences, they begin to notice-- the text has changed! But, they never saw it change. The testers used a computer to sense where the eye was pointed away from other areas of the text, and at that moment changed the text. The reason the person didn't see the text get changed is because your eyes are always scanning, and they really only focus on a tiny tiny area at once, of only like one word. They are scanning very very quickly, faster than you can conceptualize if you're asking this kind of question. So even though you see the entire page in your mind, most of this is a reconstructed memory of what you've just seen- even if you haven't read it all yet. So if anything but the few millimeters you're focused on at that instant changes, you wouldn't see it, even though you think you "see" most of the page.

Another interesting fact is that if you wear lenses that turn everything upside down, after about a day, everything will suddenly lookk rightside up. When you remove the lenses, everything will look upside down again for a few hours.

Optical Illusions websites will probably give you some more explanations on how the eyes see and the brain perceives.

Answer 2

The brain is able to integrate information from the motor and vestibular systems to keep track of the movements of the body. If you are moving your body yourself, your brain knows it because it has access to those motor commands. If your body is moved by outside forces, the vestibular (or balance) system gets information from the inner ear that tells it which direction and speed the body is moving. In either case, the visual system is able to take that information and compensate for the movement on the retina. Also, there is usually context from the whole environment that helps distinguish what is moving and what is static.

Answer 3

I do believe the brain's visual reception system 'switches off' periodically for milliseconds at a time during actual eye movement, so avoiding blurring or 'camera shake'. Try this! - it's amazing but true! Look in a mirror close up, then let your eyeballs track to one side. You will not 'see' the eyeballs moving, only their resting position! Your brain has switched your visual reception off during the brief period of motion.

Answer 4

because all the other entities are hardwired into the subconcious to prevent concious overload...There are only certain things you can have in your concious mind at a time...conciousness is a very big program and takes a lot of space and processing power--to prevent from overload...there is a hardwired "switch" that takes out some of the data so it does not "reach" your concious entity...

mind you, if it did, you may end up with two concious entities...and this is bad because it leads to problems, for practical conciderations in daily life.