Facts about Eyes

Human Eye

Our eyes are constantly moving, usually in rapid jerky movements. But your brain has a kind of ‘steadycam’ feature which makes your vision seem to be stable.

When you were born you had blue eyes. It was only after exposure to light that they became the colour they are now.

Even the tiniest of noises automatically makes your pupils change focus.

Your eyes stay the same size throughout your life as they were when you were born - but your nose and ears will continue to grow until the day you die.

As you get older, the lens in your eye grows thicker - this is why people who had perfect vision when younger need glasses as they advance in years.

When you blink, it lasts for about one tenth of a second.

Scientists believe that processing your vision uses around half of the brain’s power.

Each of your eyes has a blind spot - where the optic nerve attaches to the retina. The brain is just smart enough to fool you into ignoring it.

In an experiment, people were given glasses which flipped their vision upside down. Within a day, those people’s vision had corrected itself so the brain interpreted the world the right way up. Amazingly, when the glasses were eventually removed, the same thing happened - it took around a day for the brain to adjust again.

Your eyeball weighs around 30 grams.