Children’s Vision

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A child’s development includes the development of vision in both visual thinking (often-called visual perceptual skills) and the visual abilities of eye teaming, focusing and eye movements (fixation, saccades and tracking).

Your child’s vision may be clear enough but they may not have developed the appropriate visual skills for reading. When reading, it is necessary for a child to keep their place along a line of text (tracking skills) while moving from word to move (saccades) as well as keeping the page in focus at the same time (focusing skills). A child with eye movement or focusing difficulties is therefore more likely to have difficulty with reading.

To read left to right partly requires accurate eye movements but also depends on Visual-Spatial skills. The left to right nature of sequencing sounds in words and sentences can be a difficult concept for a child with visual spatial difficulties to grasp. A child who has not understood or adequately organised the necessary aspects of visual spatial will most likely have difficulty with learning to read.

As a child progresses through the grades the demand on visual skills, and the need for more automatic visual skills increases. Primary visual skills required for early readers are listed below but more complexity and integration increases with academic demands.

  • Tracking and saccades

This is the ability to point the eyes accurately at an object and to keep the eyes on target whether the object is moving or stationary. Without these skills, you can’t clearly follow a moving object, such as a ball in flight. You can’t move your eyes smoothly across a line of text on a page. Scanning from letter to letter, word to word, looking ahead and predicting text, moving from one line to the next are all complex eye movements that are involved in the skill of reading.

  • Eye teaming (binocular fusion and stereo depth perception)

The ability to co-ordinate and align the eyes precisely so that the brain can fuse the images from each eye. Even a slight misalignment causes difficulty with reduced attention and stamina for visual tasks, particularly reading. Misalignment causes double vision or suppression of part of the vision of one eye, making precise tasks more exhausting.

  • Focusing skills

The ability to accurately focus and maintain clarity at a particular point (a word on a page) and the ability to rapidly change focus from one point to another (copying from the board to the book). Most children are capable of a large amount of change in focus, but fine, accurate control breaks down more easily under stress.

An assessment of these visual functions is included in a thorough visual efficiency examination carried out on a child brought to our practice. Specific tests given will vary with each child’s individual needs. Besides the review of the child’s health history and an examination to confirm the eyes’ physical health, the vision examination by the optometrist includes:

  • a test of the child’s ability to see sharply and clearly at near and far distances
  • tests to determine refractive status (nearsightedness, farsightedness and focusing problems)
  • a check of the eye co-ordination to be certain the eyes work as a team at both distance and near
  • a test of the ability to change focus easily and accurately from near to far and vice versa
  • a check for any sign of crossed eyes or any indication that the child is not using one eye
  • a test of depth perception.