University researchers have
found that more than
85% of dyslexics are helped by tinted lenses.
Researchers think dyslexia may involve an
abnormality that slows down one of two major visual pathways in the brain so that two
kinds of visual information are not received in the right sequence. One pathway, the
magnocellular system, has large cells that carry out fast processes for perceiving
position, motion, shape and low contrast. The smaller parvo cells carry out slower
processes for perceiving still images, color, detail and high contrasts.
In reading, light strikes photoreceptors in the retina; the information is then processed
by magno cells and parvo cells in midbrain regions called the lateral geniculate bodies.
Then the signal travels to the visual cortex for further processing. In a study of
dyslexics, the magno cells were found to be smaller than normal, and low-contrast
information processing was found to be slower than normal.
It has been found that reading through blue filters helps 80 percent of the
children read better, and 8 percent are helped by red filters.
Exactly how the filters help the problem remains a mystery. The nerve cells of the fast
magno pathway are inhibited by diffuse red light, so that a blue filter may remove enough
of the red in what a dyslexic person sees to thus allow the magno cells to work normally.
At the 1995 Annual Meeting of the American Academy of Optometry in New Orleans, Harold A.
Solan, O.D. M.A., a leading reseacher and practitioner in the area of children's vision
training, presented the results of his most recent research project. He found that 87% of
reading disabled children showed an improvement in comprehension while reading with blue
filters. Dr. Solan and his associates (Julie Brannan Ph.D., Anthony Ficarra O.D., Robert
Byne O.D.) focused their attention on children with a specific reading disorder (SRD).
BPI Dyslexia PC Research
2 software modules for auditory and visual evaluation of dyslexia
symptoms. (For IBM PC's and 100% compatible clones)
The BPI Neurological Diagnostic System .
Twelve different flippers to aid in further research.
BPI also has research information available.