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Visual Processing Disorders
in Children
Vision & Math
Vision & Reading
Vision & Writing
Vision & Social Problems
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The Whys of Visual Processing
The Long Distance
Travel of Visual Information
When we see, the visual information comes through our
eyes, but it has to travel a long way inside the brain
before it reaches the visual cortex. On it's way, the
brain organizes its self into different meaningful bits
of information - objects, scenes, and people (Visual
"What"), and positions and locations (Visual "Where").
Because the signals travel from the eye to the back of
the head, there are many sites where pathways can be
come partially damaged. In some cases, like premature
birth, pathways may just be immature.
The animation below shows the path of visual information
from the eye to the visual cortex. After information
arrives in the visual cortex, it can be processed
further and coordinated with other sensory systems to
help give rise to multisensory images and internal
representations.
Click here to see animation.
Why Visual Processing Problems are
Hard to Recognize
Visual processing
problems are hard to recognize because the problems in
vision are incomplete, and children don't know what
normal vision is supposed to look like.
Partial damage to the "Visual What" pathway may make it
harder to "see" objects from a busy background
because they can't distinguish whole shapes well. These
children may struggle with finding things, and leaving
exasperated parents to mutter, "What do you mean you
can't find it - it's right there in front of you!"
Partial damage to the "Visual Where" pathway may be even
more confusing to parents and teachers because bright children may
develop inexplicable problems with reversals and rotated
figures. Impairment in this visual spatial pathway may
cause kids to make surprisingly obvious errors with
visual matching or drawing.
Visual associational areas work downstream from
primary visual pathways, but as a result they can be
directly or indirectly affected by damage to visual
pathways. Some children report a complete absence of
visual imagery. Said one of our young students, "My
teacher's always telling me to make a picture in my
imagination. I never know what that means. I can't make
any picture in my head."
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