Symptoms and causes


Not everyone with convergence insufficiency has signs and symptoms. Signs and symptoms occur while you're reading or doing other close work and might include:

  • Tired, sore or uncomfortable eyes (eyestrain)
  • Headaches
  • Difficulty reading — words seem to float on the page, you lose your place or you read slowly — which might cause you to avoid reading or not complete schoolwork
  • Double vision (diplopia)
  • Difficulty concentrating
  • Squinting, rubbing or closing one eye

When to see a doctor

If you or your child has symptoms of convergence insufficiency or problems reading, consult an eye care professional — an ophthalmologist or an optometrist.


The cause of convergence insufficiency isn't known, but it involves a misalignment of the eyes when focusing on nearby objects. The misalignment involves the muscles that move the eye. Typically, one eye drifts outward when you're focusing on a word or object at close range.


Difficulties with reading and concentrating can affect a child's learning. Convergence insufficiency does not cause learning disabilities, but it makes using your eyes difficult and tiring.

Convergence insufficiency typically isn't detected in routine eye exams or school-based vision screenings. Reading difficulties of children with the condition might lead to an evaluation for learning disabilities, but it's important to rule out this eye disorder.