  During reading, dyslexic readers exhibit more and longer fixations than
normal readers. However, there is no significant difference when dyslexic and
control readers perform only visual tasks on a string of letters, showing the
importance of cognitive processes in reading. This linguistic and cognitive
processing demand in reading is often perturbed for dyslexic readers by
perceived additional letter and word mirror-images superposed to the primary
images on the primary cortex, inducing an internal visual crowding. Here we
show that whereas for a normal reader, the number and the duration of fixations
remain invariant whatever the nature of the lighting, the excess of fixations
and total duration of reading can be controlled for a dyslexic reader using the
Hebbian mechanisms to erase the extra images in an optimized pulse-width
lighting. The number of fixations can be reduced by a factor of about 1.8,
recovering the normal reader records.
