The evidence Professor Evans presented indicated that binocular instability
is prevalent in 15% of dyslexics, compared to 5% in those with higher literacy.
The six-year-old, of Whitley Bay, had struggled to keep up with his classmates at Appletree Gardens First School in Monkseaton until he was diagnosed with binocular instability.
Binocular instability is often linked to dyslexia and Josh, who has three brothers - twins Alfie and Toby, sevenmonths, and Jamie, 17 - will undergo tests to see if he has the condition.
18) Movement or intermittent flashing of the nonius markers indicates binocular instability
Patients with convergence or accommodation deficiencies, or binocular instability
, typically attend complaining of similar symptoms.
18) Fixation disparity assessment particularly included a report of whether the patient observed any movement of the nonius markers; the presence of movement but no misalignment indicated binocular instability
The main visual problems that are correlated with dyslexia are Meares-Irlen syndrome/visual stress (MISVIS), binocular instability
, and accommodative insufficiency.
is characterised by low fusional reserves and vergence instability and can cause symptoms including diplopia, blur, visual perceptual distortions and headaches.
34) It remains to be seen whether the M deficit directly causes these visual confusions, whether the M deficit causes binocular instability
which in turn causes confusions, or whether both confusions and binocular instability
are the result of some other causal link.
, decompensated heterophoria, or accommodative insufficiency) it can be helpful to investigate the effect of borderline refractive corrections on the ocular motor status.
is characterised by an unstable heterophoria and low fusional reserves.
BBC Radio 4's Monday (October 13) edition of Through the Looking Glass discussed binocular instability
, a condition that affects 15% of the population and leaves sufferers unable to read without experiencing headaches.