I see a group of fuzzy hairs attached to a medium sized four-legged creature. A large pink object attached to a smaller portion of the figure is approaching my face. And it is my dog, licking my face at 7am.*
What I’ve just described is the process of visual perception. I see a bunch of parts and assimilate them to make meaning of them. The same process goes for learning to read. I see little squiggles and perceive them to be letters, combining into words. When you think about the process of visual perception in depth, it is actually quite complex. The same goes for assessing if a student has a “visual processing deficit” that constitutes a learning disability. I have never seen two children with the same “visual processing deficit.” That term is really an umbrella for a number of processes, in the same way “auditory processing” encompasses so many different things.
At the risk of oversimplification, here are the main things a school or educational psychologist may look for when assessing this area of processing:
1) Accurate Vision: One would think that is goes without saying that if a student has not passed a vision screening test that it would be impossible to accurately measure their visual perception. One would be wrong. I constantly refer families for vision evaluations before I test their child’s perception. Remember, you must be able to accurately see something in order to perceive (make meaning) of it. To take it to the extreme, it would be like showing a Rorschach ink blot to a blind person and asking them what it looks like to them.
2) Visual Perception: This one is the fodder for every Intro to Psychology course. What do you see in this picture:
If you said a young woman, you are correct. If you said an old woman, you are correct. Depending on what features you look at, it can be either. Go on, try again. Finding the old woman always takes me a minute. I’m not ageist, I promise.
So basically, visual perception is taking the parts and assimilating into a whole in order to make sense of it. A student with visual perception problems may take more time to perceive visual stimuli. To simplify, a student may misperceive a “b” for a “d,” have difficulty reading a graph, struggle with taking in lots of visual information, have difficulty putting together puzzles, and/or have to exert more mental energy to scan for important pieces within the whole (such as locating something on a map, finding the section in the book you need, or finding that stupid little Waldo guy in the midst of many similar Waldo-esque objects). There are a number of tests that one might use to discover which aspect of visual perception is impaired.**
3) Visual Memory: Okay great, let’s assume your brain has accurately registered what you are seeing. But can you remember it? Can you remember the details of a picture in your mind and call it up later? Can you remember that this thingy b is called “b” and it’s a line with a bubble on the right? If you can’t, then your visual memory may be impaired. Visual memory is usually measured by showing a student a shape s/he has never seen before and then showing a bunch of similar shapes and asking her/him to find the one they saw.
4) Visual Sequential Memory: This is the same as visual memory, only you not only have to remember what you saw, but also in what order. So I would typically show a student several shapes in a row and then ask them to remember the order in the midst of several choices with similar orders. If you think about it, this process can be involved in reading, as you must remember that these squiggles bed mean something different than theses squiggles deb.
I should note that though most “classic” learning disabilities are auditory in nature, at times, visual processing is the processing deficit that is preventing reading. More often, visual processing deficits affect math and science. Why? Because there are a lot of symbols involved as well as visual representations without language (think of those plotting numbers on the X and Y axis). Sure, it has a verbal label, but the process involved in doing something like this correctly involves far more visual processing skills.
And because nothing is ever straightforward when it comes to psychoeducational assessment, visual processing deficits taken to the extreme, can affect social perception (is that a mad face? What does shrugging shoulders mean?). When there are social impairments too, one has the unique challenge of figuring out if the student also has a Nonverbal Learning Disability, which is sometimes considered a disorder on the Autism Spectrum.
* Puppy apparently did NOT get the memo that it is summer break and mommy doesn’t have to get up at 7 every day. 
**For those interested, send me an email and I’ll tell you my favorites. rebeccabell@studentsgrow.com
So here is my question. How can a child who has a talent for drawing, a passion for art and a visual learning style possibly have a visual-motor processing deficit? Yet, by all accounts and professional testing, that is the problem. Why does a child who notices the small details miss the big details?
I have had this quandary before as well. Some of the kids I’ve tested cannot scan and circle a simple worksheet of numbers, but can produce gorgeous real-life portraits and art. One aspect I can speak to is the timed aspect. Sometimes it’s not the actual physical act of writing/drawing, but the time it takes to plan and execute the writing/drawing. The student I referred to who did great portraits took DAYS to do the work, and constantly drew and erased until it looked right.
Then, there are those kids who can perceive visual information well, but the integration is the problem. There are the kids who can draw fine, but struggle with the planning (like the ones who start to write a sentence and run out of space on the right side every time).And there are kids who have used strong verbal skills to compensate and look fine, but still struggle. I don’t have the answer, but I do know that each kid with a “visual motor deficit” looks very different each time.