There are many interesting facts about eyes, like did you know that everyone with blue eyes shares one common ancestor? But there are many misconceptions too.
A lot of us are warned as children about how some things we do every day could harm our eyes. Do you know which of these statements are actually true?
- Sitting too close to the television can damage children’s eyes
- Colour blindness is more common in males
- Sneezing can make your eyes pop out
- Your eyes see upside down
- Reading in dim light is harmful to your eyes
Read on to learn the truth!
Sitting too close to the television can damage children’s eyes.
Don’t tell your kids but… but there is no evidence that this practise is causes eye strain or damage of any kind. As children can focus more easily than adults at close distances, they often develop a habit of sitting very close to the television. Children who are short sighted will also sit close to the television in order to see more clearly.
Reading in dim light is harmful to your eyes
This will not cause damage to your eyes. You must remember that it was only during the last century that high quality electric lighting became commonplace. Before that the only thing that people could use to help them see at night was candle light, wood or coal fire places and small gas or oil lamps.
It is, however, easier and less tiring on your eyes to read in good lighting.
Colour blindness is more common in males.
It is estimated that around 8% of boys have some level of colour blindness compared to less than 1% of girls. The most common type of colour blindness affects people’s ability to distinguish red and green shades.
Tests for colour blindness can be carried out using the Ishihara Test. See for yourself, can you read what it says?
Sneezing can make your eyes pop out
Most people fully close their eyes when sneezing, but this is due to reflex. And it is possible for some people to sneeze with their eyes open. There is also no evidence to support that the reason your eyes close when you sneeze is to prevent your eyes from popping out!
All eye movements are powered by muscles which are firmly attached to the eyes, and these keep your eyes exactly where they belong. So, if the eyes are attached so securely, why is there a widespread belief that sneezing with your eyes open will blow them out of your eye sockets?
Perhaps the fact that it is almost impossible NOT to blink when you sneeze has led to this tale.
Your eyes see upside down
When images enter your eye, they are actually viewed upside down!
Eyes see upside down because of the way they process light, and your brain is a huge factor in the way you see the world. Such a complex task as processing visual information takes up a large portion of the brain compared to other senses. Your brain has to process images to make them appear logical. The brain’s main tasks are to combine the two separate images seen through each eye and to make images appear to be the right way up.
Your brain is so used to seeing things upside down that it eventually adjusts to it. This is because it is a lot easier to coordinate your actions with this flipped over image than to try and exist in an upside down world!
As a result, though, it is believed that for the first few days, babies see everything upside-down. This is because they have not become used to vision.
Here’s one more fact for you – amazingly, your brain can be retrained.
In one study, participants were asked to wear glasses with lenses that inverted images before they reached the eyes. At first, everything appeared upside down to the participants. But after a few days, people began to report that everything appeared to be right way up again.
For the second part of the study, the participants were asked to take the glasses off. But because they were now used to the inversion lenses, their normal vision appeared to be upside down. Within a day, their vision did return back to normal.
So in summary, the reason you don’t see everything upside down is just because it’s easier to understand things when they are the right way up!
Guest Author: Christina Romano is interested in all things optical. She writes for online retailer Lenstore contact lenses