In the previous article we spoke about sensory discrimination and the different types of discrimination there is. It was mentioned that discrimination and perception problems can occur in any of our sensory systems. Today we are going to focus on visual discrimination.
Visual discrimination helps us to recognize, match and place different objects, forms and pictures in to categories. Recognition is our ability to see features and relate them to something from our memory. Matching is our ability to see the similarity of things. Categorization is our ability to determine the category in which similarities and differences can be seen. We need recognition, matching and categorization in order to discriminate between the differences or similarities of forms, objects and pictures and to be able to relate what we have seen to the information stored in our long-term memory.
So, visual discrimination can be divided into 2 sections namely object vision and spatial vision. Object vision helps us to identify objects by their colour, texture, shape and size whereas spatial vision helps us to know where objects are in space.
Let’s discuss these two types of visual discrimination in a little môre detail:
Object (form) perception involves many different visual areas in our brains and it can be divided into form constancy, visual closure and figure-ground recognition. Form constancy helps us to recognize forms and objects as the same when they are presented in different positions or sizes. Form constancy helps your child to recognize a number or letter when it is written in a different font or size. Form constancy is important for children in order for them to read, write and copy work from a board.
Visual closure is our ability to see an incomplete picture as a whole. It helps children to identify and recognize shapes and forms by completing an incomplete picture in their minds. This is also needed to help children with their drawing and writing skills.
Figure-ground recognition is our ability to find an object on a busy background. These skills are needed for reading and to be able to find objects we need in a cluttered environment.
Now for the second type of visual discrimination, which is our spatial perception and includes position in space, depth perception and topographic orientation.
Let’s discuss and see what each of the terms entail…
Position in space is our ability to identify the position of an object in relation to yourself or another object. It is important in order to understand directional language such as up, down, in front, behind, left and right. Position in space is also an important factor when writing letters or words and is needed to ensure that there is adequate spacing between your letters and words.
We need depth perception to help us to determine how far away an object is and it helps us to move in space for example to be able to walk down stairs or catch a ball.
Topographic orientation helps us to determine where an object is and what route we need to take to get to the object. Without topographic orientation your child will find it hard to get his way back to the classroom or his desk.
So you might think, how am I going to know if my child has visual discrimination difficulties?
Here are a few things to look out for.
Does your child:
- Struggle to identify a letter or word in different fonts or sizes? (They might have form constancy difficulties)
- Struggle to identify a whole picture from an incomplete picture? (They might have visual closure difficulties)
- Struggle to find an object from a busy background like finding a specific toy on their shelf of toys? (They might have figure-ground difficulties)
- Struggle to understand terms like the ball is on top of the chair or crawl under the table and they make letter reversals during writing? (They might have position in space difficulties)
- Struggle to catch a ball and find it hard to copy from a board? (They might have depth perception difficulties)
- Struggle to find his way home from school or gets lost easily? (They might have topographic orientation difficulties)
- Struggle with reading, spelling, hand writing and mathematics? (They might have visual perception difficulties)
Activities you can try at home to improve your child’s visual discrimination:
- Where’s Wally games
- I Spy (with my little eyes) games
- Placing pegs in a peg board
- Finding the differences in pictures
- Completing mazes
- Building puzzles
- 'Simon Says' using positional words (climb on the chair, crawl under the table)
- Matching games (matching colours, shapes, clothing items, toys)