Reading requires the accurate coordination of many visual skills. This includes aiming both eyes at the same point simultaneously (binocular vision), moving both eyes continually as a coordinated team across the line of print (ocular motility), and maintaining focus with both eyes to make the reading material clear (accommodation). Each time we move our eyes to the next line of print, we continue with the process.

In order to gain comprehension throughout the reading process, we are constantly taking in the visual information and decoding it from the written word into a mental image. Memory and visualization are also used to constantly relate the information to what is already known and to help make sense of what is being read.

Writing is similar to reading, but almost works in the reverse order to reading. We start with an image in our mind and code it into words. At the same time, we control the movement of the pencil while continually working to keep the written material making sense. Throughout all this, we focus our eyes and move them together just as in the reading process.

Handwriting is greatly influenced by visual-motor development. Visual-motor integration is the ability to coordinate visual information processing with motor skills. Improvements in visual processing and eye-hand coordination skills when the child is still actively and consciously controlling hand movements (grades K-3) leads to immediate improvement in writing skill.

Spelling can be accomplished in several ways. Some people memorize the sequence of letters and use aural reinforcement, ie spelling out loud. Others use visualization, reaching for a pencil to write the word to see if it “looks right.” Visualization is more efficient, particularly for phonetically irregular words. Patients who cannot spell may suffer from deficient visualization abilities or may be dyseidetic.

The primary objective of vision therapy is to improve visual memory and visualization. Naturally, improvement in visualization cannot replace the need of exposure to written material because a word cannot be visually recalled if a child has not experienced the word. A major non-visual basis for spelling difficulty is a lack of reading.

Vision and mathematics are related in several ways. Children with poor visual spatial skills may have difficulties in acquiring the fundamental understanding of the relationship between numbers and value. Memorizing that 2 plus 2 equals 4 has little utility unless the child can appreciate that the numbers 2 and 4 are not simply figures but represent specific magnitudes.

Early math teachings usually include methods utilizing visual cues to associate numbers with magnitudes. Visual spatial thinking and the ability to visualize and mentally manipulate shapes also become important for learning higher level math topics such as geometry and trigonometry.

Oculomotor difficulties can also play a role in mathematic by causing “careless” errors such as omission of a number, inadvertent shifting of one number when adding or subtracting, or incorrect copying of math problems from the board or a book. A child who shows good performance with oral arithmetic but poor performance at written arithmetic is highly suspect of for visual interference.