Understanding Visual Processing Disorder
What is Visual Processing?
Visual processing is the brain’s ability to make sense of the messages it receives from the eyes. It allows the brain to tell one thing from another, to distinguish colors and shapes, to understand the way an object is oriented in space, or to control where parts of the body moves around the things it sees. The ability to interpret visual input also allows the brain to figure out what an object is even if only part of the object has been seen. For example, by seeing a branch with green leaves, a student can deduce that it is part of a larger tree. Without the ability to decode visual messages, she/he might confuse a tomato with an apple, or might have difficulty parallel parking due to poor depth perception. Visual processing is also responsible for the brain’s ability to remember, in the short and long term, what the eyes see.
How Does It Work?
According to Drs. Brock and Fernette Eide, when the brain receives information from the eyes, the information gets sorted into different categories before reaching the visual cortex at the back of the head. The data is then assimilated together, and the brain can understand certain things about the perceived object: what it is, size, location just to name a few examples. The process is similar to a network of train tracks that take separate routes, but all converge into a central hub. If any of those routes are malfunctioning, the entire system can be thrown off.
Signs of Visual Processing Disorder
A dysfunction in visual processing can manifest in a number of ways depending on which pathway is affected.
- Object recognition can be affected causing difficulty in areas like reading (i.e. letter recognition or sight word memorization).
- Trouble with spatial relationships may be marked by confusing lefts and rights, misjudging distance between objects, or mixing up letters like "p and q."
- Visual closure is the ability to discern an image when part of it is missing. To use the tree example, without this way of interpreting information, someone may see the branch and not recognize that it is part of a larger tree.
- Finally, if an individual is unable to spot differences between similar objects, he has trouble with visual discrimination.
Strategies and Interventions
Once the type of dysfunction has been determined, there are some concrete tools and strategies that can be helpful:
- Larger print reading materials with well spaced words or numbers
- Markers or other means of ‘tracking when reading to block out material that is not the immediate focus
- Highlighting when reading
- Tools like computers or recording devices
- Paper with guides like graph paper or larger-lined paper
- ‘Find it’ games like the I Spy series to build visual discrimination skills, or jigsaw puzzles
While the skewing of any information received by the brain is concerning, with appropriate support, students can learn to manage these difficulties. Visual interpretation issues sometimes can be addressed with corrective lenses or by strengthening the eyes. Occupational therapists and special educators can often provide assistance and can help students to develop coping skills to deal with their specific issues. With aid, tools, and understanding, visual processing challenges can be overcome.