There are lots of ways the brain processes visual information. Weaknesses in a particular kind of visual processing can often be seen in specific difficulties with practical, everyday tasks. Weakness can occur in one or more category at the same time.
Many people without any kind of visual processing disorder experience problems with learning and behavior from time to time. However, if a person consistently displays difficulties with these tasks over time, testing for visual processing disorders by trained professionals should be considered.
Visual Discrimination
The Skill: Using the sense of sight to notice and compare the features of different items to distinguish one item from another.
Difficulties Observed: Seeing the difference between two similar letters, shapes or objects; noticing the similarities and differences between certain colors, shapes and patterns.
Visual Figure-Ground Discrimination
The Skill: Discriminating a shape or printed character from its background.
Difficulties Observed: Finding a specific bit of information on a printed page full of words and numbers; seeing an image within a competing background.
Visual Sequencing
The Skill: The ability to see and distinguish the order of symbols, words or images.
Difficulties Observed: Using a separate answer sheet; staying in the right place while reading a paragraph (example: skipping lines, reading the same line over and over); reversing or misreading letters, numbers and words; understanding math equations.
Visual Motor Processing
The Skill: Using feedback from the eyes to coordinate the movement of other parts of the body.
Difficulties Observed: Writing within lines or margins of a piece of paper; copying from a board or book; moving around without bumping into things; participating in sports that require well-timed and precise movements in space.
Visual Memory
The Skill: Long-term visual memory is the ability to recall something seen some time ago; short-term visual memory is the ability to remember something seen very recently.
Difficulties Observed: Remembering the spelling of familiar words with irregular spelling; reading comprehension; using a calculator or keyboard with speed and accuracy; remembering phone numbers.
Visual Closure
The Skill: The ability to know what an object is when only parts of it are visible; recognizing a picture of a familiar object from a partial image (example: a truck without its wheels); identifying a word with a letter missing; recognizing a face when one feature (such as the nose) is missing.
Spatial Relationships
The Skill: The ability to understand how objects are positioned in space in relation to oneself. This involves the understanding of distance (near or far), as well as the relationship of objects and characters described on paper or in a spoken narrative.
Difficulties Observed: Getting from one place to another; spacing letters and words on paper; judging time; reading maps.