The Role of Vision in Learning

Presented on Friday 7 November 2008

General Advice and Conclusion

Nadia Northway
PhD BA DBO SRO

Eye Care Protocol

Correct binocular vision problems first
Children should have trial with overlay and reading should e measured with and without colour to show effect. Trial should last 12-16 weeks
Colour: If positive effect on reading speed and visual comfort then prescribe precision tinted lenses
Rarely use overlays in people over the age of 14
Treat motor visual problems and then visual perceptual problems.

Teacher Protocol

Request parents take child for routine test
Use Visual Stress Index
Ask for referral to Orthoptic Department if BV problems seem to exist
Try overlay with child
If positive response to overlay then coloured lenses should be prescribed- see local protocol
Change the ASL Act (2004)
Writing- consider vision as causal factor for poor writing not just motor control.

Coloured Lenses

Research has confirmed that some accuracy required in tinting lenses to maximise visual comfort
May be prescribed for reading only or general wear
Minimum tint required should be prescribed
Tint may not match overlay
Controversy caution

Significance of Visual Problems in Poor Readers

Greater impact
Diagnosis of orthoptic problems and visual stress of paramount importance because:
High risk group
Less tolerance for visual disturbance due to greater cognitive demands with poor readers
Fatigue effects - poor readers will take longer to carry out work so visual skills need to be adequate
Two or three barriers to reading instead of one

Observations and Causes

More to improving reading than just using a coloured overlay - Any of the symptoms on the left may be caused by any of the causes on the right

Fatigue	Poor convergence, jump convergence
Headaches	Strabismus or poor binocular vision
Double vision	Poor accommodation amplitude
Blurring of print	Scanning/Tracking problems
Movement of print	Meares-Irlen syndrome/Visual stress
Restlessness	Saccadic eye movement problems
Missing words and lines	Attentional problems
Head Movement	Motor skills problems such as DCD/ Sensory Integration Dysfunction
Letter/ word reversals	Poor visual perception
Losing the place
Word/Letter substitution
Inconsistency
Poorly spaced hand writing
Poor hand writing formation
Organisational difficulties

Conclusions

Poor readers may have motor and perceptual problems with vision which affect literacy.
Improving vision can aid literacy but problems not assessed in detail in routine eye test specialised testing required.
Differential diagnosis of BV and Visual stress.
Improving vision can improve accuracy, fluency and ultimately comprehension of reading.