Checking to see if someone has a visual problem that is affecting their reading/writing
( note I am not an optician, This is a biologists view of the issue)
If you are trying to help yourself or someone else to understand if they have an unresolved but resolvable visual problem which can make your dyslexia seem worse, or perhaps be the root cause
Then try the following.
Does the person need glasses?
1. Hold a pen in front of one eye and close the other. Start with the pen about 10 cm in front of the open eye.
a. Move the pen slowly back and forth
b. If it is out of focus and
i. Gets clearer then less clear as you move it to arms length, then… You have a short sight problem.
ii. If it gets clearer then stays clear, then…ok.
iii. If it stays out of focus even when your arm is outstretched, then…. the eye is probably longsighted.
2. Try the other eye. Same questions.
3. If the two eyes are different, for example .one long sighted and one short sighted then you will probably suppress one ( and get easily distracted) when reading.
This could result in an eye turning sideways and getting a pain around one eye, after a period of reading.
4. The other possibility is an astigmatism in one or both eyes. Quite common but often not corrected if in one eye only.
An astigmatism is slightly more difficult but not really hard to identify.
a. Draw a large capital L on a page. About 5 cm tall and wide.
b. Hold it in front of one eye (the other eye closed) at the closest point at which the eye was focussed.
c. If the vertical or the horizontal is fuzzy and the other is sharp then you have an eye ball with an uncorrected astigmatism.
d. Swap eyes and test the other.
If uncorrected with glasses then an astigmatism will slow down data collection from that eye. If one eye is worse then the eye will be suppressed and may turn to one side, cause eye aches and reduce reading stamina.
How will this affect dyslexia in that poor visual data collection will make extra demands on already limited working memory and make the situation unnecessarily / avoidably worse.
Also if the reading is slower you have to hold the ideas/images in memory for longer time periods which will stress working memory which can be considered as having a time limit as well as a capacity limit. So the beginning of the sentence has ‘disappeared before you get to the end of it.
5. If both eyes very short-sighted thus can be linked with the eyes finding it hard to ‘turn in’ to prevent a sense of double-vision.
This will lead to the book being needed to be gradually moved away from the face until it gets out of focus. Often short-sighted people are very fast readers but only in short time bursts with lots of rests/gaps needed.
6. If an eye is turning out for some reason, the head is often turned sideways, or it is accompanied by head -shaking/fidgeting/..
Even if you have glasses, you may be suspicious of whether they are correct. Following the above checks with your glasses on can help you in deciding what to do next.
If you have problems then go back to the opticians?