Some vision problems can make words on a page look like this.

Symptoms that may indicated a need for vision therapy


Some vision problems can make text look like the examples above.  That is why the vision problems that are treated with vision therapy can make it difficult for a child to read and learn effectively.


Convergence insufficiency


One of the most common eye movement disorders is convergence insufficiency, where the eyes don't work properly when doing near work like reading and other school work. A study funded by the National Eye Institute has found that vision therapy is the best treatment for convergence insufficiency. Convergence insufficiency can make a book look like this:




When Is a Learning Difficulty Due to a Vision Problem?

While learning occurs through a number of complex and interrelated processes, vision plays a key role. Many signs, symptoms, and behaviors associated with learning disabilities are similar to those caused by vision problems. This is why it is so important that a comprehensive vision examination be part of the interdisciplinary evaluation of all children who are failing to succeed in school. For example, a recent study, which adds to a large body of research, found that 60% of students who were on an individual learning plan due to reading or other academic problems failed two or more binocular vision tests.


You can print the Symptoms Checklist and bring it with you to your appointment. It is helpful if you have your child’s teacher review the checklist as well to let you know which signs she is seeing in the classroom.

Symptoms and corresponding vision problems


The following table of symptoms and possible vision problems comes form the College of Optometrists in Vision development. If you or your child exhibits some of these symptoms, you should see a developmental optometrist. If you don't live in the metro Vancouver area, click here to locate a doctor.



Possible Vision Problems

-Complains of blurred vision
-Rubs eyes frequently

Nearsightedness, Farsightedness, or Astigmatism (inability to see clearly in the distance or up close)

- Closes or covers one eye
- Occasionally sees double
- Rubs eyes frequently
- Able to read for only a short time
- Poor reading comprehension

Eye coordination problems (inability to coordinate the eyes together effectively)

- Holds things very close
- Complains of blurred vision
- Poor reading comprehension
- Says eyes are tired
- Able to read for only a short time
- Has headaches when reading

Eye focusing problems (inability to easily refocus eyes or maintain clear focus)

- Moves head excessively when reading
- Frequently loses place, skips lines when reading
- Uses finger to keep place
- Poor reading comprehension

- Short attention span

Possible Vision Problems: Eye tracking problems (inadequate ability to smoothly and accurately move the eyes from one point to another)

- Mistakes words with similar beginnings
- Difficulty recognizing letters, words, or simple shapes and forms
- Can't distinguish the main idea from insignificant details
- Trouble learning basic math concepts of size, magnitude, and position

Faulty visual form perception (inability to discriminate differences in size, shape, or form)

- Trouble visualizing what is read- Poor reading comprehension
- Poor speller
- Trouble with mathematical concepts
- Poor recall of visually presented material

Faulty visual memory (inability to remember and understand what is seen)

- Sloppy handwriting and drawing
- Can't stay on lines
- Poor copying skills
- Can respond orally but not in writing

Faulty visual motor integration (inability to process and reproduce visual images by writing or drawing)

- Trouble learning right and left
- Reverses letters and words
- Trouble writing and remembering letters and numbers

Difficulty with laterality and directionality (Poor development of left/right awareness)




Ggeneral signs and symptoms to look for that may indicate a vision problem

People with eye-muscle or visual-perceptual problems typically present with one ore more the following symptoms.  However, to know if you or your child's symptoms are caused by a visual problem, you must come in for a doctor's eye health examination.  Remember, the examination is still covered by the provincial government for children 18 and under.

  • Performs below potential
  • Trouble staying focused on homework
  • Moves head back and forth while reading (instead of moving eyes)
  • Loses place and skips lines when reading
  • Poor concentration
  • Misaligns letters or numbers
  • Avoidance of near work such as reading
  • Unusual posture
  • When reading, words, lines or letters run together or jump around
  • Moves head close to see a book or paper
  • Crooked or poorly spaced writing
  • Jerky eye movements
  • Eyes that cross or turn in or out
  • Difficulty tracking moving objects
  • Whispers to self when reading
  • Difficulty copying from the board
  • Poor eye hand coordination
  • Persistent reversals of numbers, letters, or words after second grade
  • Omits or confuses small words when reading
  • Loses place when reading
  • Uses finger to keep place
  • Squinting, eye rubbing, excessive blinking
  • Homework takes hours when it shouldn’t
  • Blurred Vision
  • Short attention span, quickly bored, day dreams, doesn’t pay attention
  • Becomes easily distracted
  • Low comprehension of written material
  • Can read but chooses not to
  • Light sensitivity after reading
  • Difficulty in catching a ball
  • Child is often labeled as “unmotivated”, “distractible” or “lazy”
  • Double vision
  • Turning or tilting of head when reading
  • Headaches, dizziness, nausea;
  • Fatigues easily after reading;
  • Poor attention skills/ ADD or ADHD
  • Motion sickness/sensitivity


Lack of 3D vision is a major sign of a vision disorder


If you or your child do not experience 3D movies or other images like other people, you may have just diagnosed yourself with a vision disorder. It could mean anything from amblyopiastrabismus, or even a tumour that could be life threatening. It is wise to see your optometrist right away for an eye examination.






Is your child smart in everything except school?

Convergence insufficiency infographicContent


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