What Is Visual Processing Disorder?

Visual processing disorder refers to a reduced ability to make sense of information taken in through the eyes. This is different from problems involving sight or sharpness of vision. Difficulties with visual processing affect how visual information is interpreted or processed. The person may have a difficulty to discriminate in terms of foreground-background, forms, size, and position in space. He may be unable to synthesize and analyze, and he may have a problem with visual closure.

Visual processing problems can interfere with many areas of a child’s learning, particularly reading and math. Below are a few examples of how a visual processing disorder can interfere with learning:

• Form discrimination: Whether it be the differentiation of the shape of a circle from a square, or the letter B from P, the ability to perceive the shapes of objects and pictures is an important skill for the developing child to acquire. There is hardly an academic activity that does not require the child to engage in form discrimination.

  The most obvious classroom activity requiring the child to discriminate forms is that of reading. The learning of the letters of the alphabet, syllables, and words will undoubtedly be impeded if there is difficulty in perceiving the form of the letters, syllables, and words. That the discrimination of letters is a crucial skill in the early stages of reading is evidenced by an extensive literature review conducted by Chall (1967). She concluded that the letter knowledge of young children is a better predictor of early reading ability than the various tests of intelligence and language ability.

• Size discrimination: Capital letters, being used at the start of a sentence, sometimes look exactly the same as their lowercase counterparts, and must therefore be discriminated mainly with regard to size. A person who is unable to interpret size may, for example, find it difficult to distinguish between a capital letter C and a lowercase c.

• Spatial relations: This refers to the position of objects in space. It also refers to the ability to accurately perceive objects in space with reference to other objects. A person with a spatial problem may find it difficult to distinguish letters like b, d, p, and q.

• Synthesis and analysis: Synthesis refers to the ability to perceive individual parts as a whole, while analysis refers to perceiving the whole in its individual parts. Synthesis plays an important role in reading, while analysis is of special importance in spelling.

• Visual closure: Difficulties in visual closure can be seen in such school activities as when the young child is asked to identify, or complete a drawing of, a human face. This difficulty can be so extreme that even a single missing facial feature (a nose, eye, mouth) could render the face unrecognizable by the child.