Convergence Insufficiency & Visual Stress


The two eyes working together as a coordinated team is called binocular vision (binocularity), and it is responsible for much of our depth perception, an extremely important aspect of vision.  For some people their eyes do not work together well and may drift outward when reading or doing up close work.  When the eyes are not working together it is called convergence insufficiency.  Symptoms typically occur after there has been a prolonged period of near vision activities, such as reading or working on the computer. It typically starts in childhood but can also occur after a brain injury.  It will not be uncovered during a typical eye exam.



  • Blurred or double vision
  • Eyestrain
  • Headache and/or fatigue
  • Squinting or covering up one eye
  • Difficulty concentrating on written material.



Visual stress is a visual perception processing problem.  It affects how the brain interprets visual information.  It can cause problems with reading and attention.


  • Headaches
  • Eye strain
  • Words appear blurry, swirl, or to move on the page.
  • Light sensitivity
  • Difficulty reading black letters on white paper because it appears too bright.
  • Visual distortions.



To diagnose convergence insufficiency or Visual stress-Irlen syndrome, a full comprehensive vision exam must be completed by an optometrist or ophthalmologist. Request a comprehensive eye exam, which is more extensive than a standard eye exam or vision screening.  Vision therapy is typically recommended and has been the most effective treatment.


What to do in the classroom if you suspect vision challenges:

  • There has been some success found when individuals put colored overlays (also called colored filters or Irlen filters) over text when reading which can alleviate some of the symptoms of these conditions.
  • Using colored paper for handouts, rather than white paper, may also be helpful.


Some organizations that diagnose visual processing problems:

Four Seasons Eye Care.  Locations in Plymouth, Minnetonka, Maple Grove, Buffalo, St Michael, Delano, Brooklyn Park, Big Lake, Mound, & Watertown.

Minnesota Vison Therapy Center.  Located in Eden Prairie.  952-844-0844,

Omni Vision Center.  Located in Monticello.  763-314-0664.


For more information:

Minnesota Department of Education, Convergence Insufficiency Fact Sheet: