Folk wisdom has long held that "the eyes are the windows of the soul". While that can lead to interesting metaphysical discussion, there is no doubt that the eyes are critical to academic success in traditional school systems.
Many people I have taught, or engaged in serious discussion, have revealed some pretty strange variations in perception. There was the good friend who saw vowels in colour, another who saw numbers in colour, the colleague who consistently perceived calendar pages as "having curved depth", the neighbour who experiences "gaps" when she scans the horizon, and the musician who perceives music "in colour and in layers" ( much like K.D. Lang who states that she "sees" music "in waves and in colour").
People only talk about these unique differences in vision and perception when they feel they have a non-judgemental audience. I have stumbled across the idiosyncrasies while trying to unravel the problems of "learning disabled" students. Many/most have areas of "giftedness" while they struggle with schooling tasks such as printing, reading, or math. Human variability raises far more questions than it answers.
Recently a new insight; this time linked to "distractibility". The optometrist of a seven-year-old child whom I tutor, has discovered a slight "bounce" in the her eye function, and links this to the child's distractibility. It is very easy to imagine how eyes like hers would "bounce" in response to any movement in her field of vision. It would also explain why she frequently "skips" a line while reading or repeats the same line. Her ability to track print fluidly is compromised.
How closely is eye-function (unrelated to 20/20 vision tests) linked to distractibility? Obviously we don't yet know. But obviously, also, schools need to keep abreast of new scientific findings and not be glib in judging children. If I've learned nothing else in 45 years of specialized teaching, I've at least learned that every child is different... and that every child deserves to be taken seriously instead of being brushed aside with a trite label.
Parents need to have very thorough vision and hearing tests performed on their child before they allow any battery of academic or psychological tests to be administered - most of these assume standard visual and auditory perception.