Understanding how your eyes work gives you the knowledge to take better care of them. NOVA Vision Center is committed to educating the community about visual health. In today’s post, your eye doctor shares some interesting facts you may not know about your eyes.
The Meaning of the Phrase “In the Blink of an Eye”
The muscles supporting your eyes and controlling their movements are some of the most active in your body. They allow you to blink at an incredible speed of 300 to 400 milliseconds — just a tiny fraction of a second — which explains the idiom “in the blink of an eye.”
The Retina Causes the “Red Eye” Effect in Photographs…
Ever wondered why you sometimes appear to have red eyes in photographs? This is actually due to your retina. The light from the camera bounces off your retina, giving you those reddish eyes in photos.
… But the Retina Cannot Detect the Color Red
While your retina has photoreceptors for red, blue and green, the red receptors can only identify yellow-green and the green ones can only detect blue-green. Your optometrist explains that your brain mixes them to recognize the color red.
Individuals With Blue Eyes Are Most Likely Related
All humans originally had brown eyes. However, a genetic mutation, the OCA2 gene, occurred thousands of years ago, leading to blue eyes. The small degree of melanin variation confirms the single ancestry of all blue-eyed individuals.
Your Eyes Can Be Different Colors
Did you know that there’s a condition that can cause people to have different colored eyes? This is known as heterochromia iridis. The right one may be green, while the other is blue.