Learning Difficulties

Question 1

Dys

Answer 1

a prefix meaning difficult or painful

Question 2

Dyslexia

Answer 2

a difficulty in reading or learning to read. Accompanied by difficulties with writing & spelling.

Question 3

Dyscalculia

Answer 3

a difficulty in performing mathematical calculations

Question 4

Dyspraxia

Answer 4

a difficulty with movement & coordination (developmental
coordination disorder)

Question 5

Dysgraphia

Answer 5

a difficulty in writing

Question 6

Dysphasia

Answer 6

difficulties in understanding language & in self-expression. Maybe subdivided into:
Expressive or motor dysphasia – good understanding of spoken language, but difficulties with self-expression
Receptive or sensory dysphasia – poor abilities to understand speech,
but good ability to speak, but this may consist of jargon words

Question 7

Meares Irlen syndrome

Answer 7

also called Irlen syndrome or Scotopic Sensitivity
syndrome. A visual perception disorder, which can cause visual discomfort &
disturbance.

Question 8

Attention deficit hyperactivity disorder ADHD

Answer 8

a lifelong condition
characterised by inattentiveness, hyperactivity and impulsivity. This is
sometimes called attention deficit disorder (ADD) with or without hyperactivity.

Question 9

Autism

Answer 9

a spectrum condition that affects how a person communicates with,
and relates to, other people. It affects how they make sense of the world
around them-more recently this is described as a problem with ‘sensory
processing’ and can affect any of the senses (not just vision and visual perception).

Question 10

Autism- three main difficulties

Answer 10

social communication, social interaction and social
imagination

Question 11

Autism findings

Answer 11

Much
research attention is focussed on autism, to try and identify the specific
pattern of difficulties experienced by each individual so that educational input
can be tailored to their needs. Researchers are working on trying to predict
who may be later diagnosed as having ASD, by looking at the traits seen in
those with emerging autism in toddlerhood. It is hoped that early diagnosis
may lead to earlier intervention and improved outcomes later. Nearly all
patients with ASD have some coexisting language impairment (dyslexia)

Question 12

Aspergers syndrome

Answer 12

a form of autism. People with Asperger syndrome are
often of average or above average intelligence. They have fewer problems
with speech, but may still have difficulties with understanding and processing
language.

Question 13

British dyslexia association BDA definition of dyslexia

Answer 13

‘Dyslexia is a learning difficulty that primarily affects the skills involved in
accurate and fluent word reading and spelling. Characteristic features of
dyslexia are difficulties in phonological awareness, verbal memory and verbal
processing speed. Dyslexia occurs across the range of intellectual abilities. It
is best thought of as a continuum, not a distinct category, and there are no
clear cut-off points. Co-occurring difficulties may be seen in aspects of
language, motor co-ordination, mental calculation, concentration and personal
organisation, but these are not, by themselves, markers of dyslexia. A good
indication of the severity and persistence of dyslexic difficulties can be gained
by examining how the individual responds or has responded to well-founded
intervention.’

Question 14

BDA noted that

Answer 14

he visual and
auditory processing difficulties that some individuals with dyslexia can
experience, and points out that dyslexic readers can show a combination of
abilities and difficulties that affect the learning process. Some also have
strengths in other areas, such as design, problem solving, creative skills,
interactive skills and oral skills.

Question 15

Orthoptics & specific learning difficulties (SpLDs)

Answer 15

In practice the Orthoptic input into SpLD services around the country varies greatly. Some Orthoptists specialise & are active in research into SpLD, &
some will have no experience of SpLD at all.

Question 16

BIOS info on SLDs

Answer 16

All specific learning difficulties (SLDs) exist on a continuum from mild to
moderate through to severe. Common patterns of behaviour and experience
do exist but there will be a range of different patterns of effects for each
individual. SLD’s are independent of intellectual ability, socio-economic or
language background.

Question 17

Figures on SLD

Answer 17

Dyslexia : 10%
Dyspraxia: 8%
Dyscalculia: 5%
Meares Irlen : 5% of the general population but up to 20% of the
dyslexic population.

Having an SLD does not predict academic potential. However, the path to
achievement is usually a lot harder and may require far greater (usually
unseen) effort and a distinct set of skills. In a study of late preterm infants
compared to term infants followed up to age 19, there was found to be no
increased risk for ADHD or learning disabilities in the late preterm group
(Harris et al, 2013).

Question 18

Dyslexia

Answer 18

Dyslexia is best described as a combination of abilities and difficulties that
affect the learning process in one or more of reading, spelling and writing. It is
particularly related to mastering and using written language, which may
include alphabetic, numeric and musical notation. Accompanying weaknesses
may be identified in areas of speed of processing, short-term working memory
and sequencing and organization. Dyslexia has also been associated with
holistic, innovative problem-solving abilities.
Some typical features of dyslexia in an academic context might be:
● a marked discrepancy between a students’ ability / understanding and
the standard of work being produced
● a persistent or severe problem with spelling, even with easy or
common words
● difficulties with comprehension as a result of slow reading speed
● poor short term memory, especially for language-based information
● difficulties with organisation, classification and categorisation
● note-taking may present problems due to poor short term memory and
language-processing difficulties
● handwriting may be poor, especially when writing under pressure
● pronunciation or word finding difficulties, which may be inhibiting when
talking or discussing in large groups

Question 19

Dyslexia- genetic and environmental factors

Answer 19

Dyslexia is thought to be caused by a combination of genetic and
environmental factors & it can be found within families (Snowling et al, 2007).
It is more common in males (Shaywitz et al, 2008). Neuroimaging studies
(summarised by Gabrieli, 2009) have identified that dyslexic individuals have:
● reduced activation in the left temporo-parietal cortex, which is thought
to support cross-modal relation of auditory & visual processing during
reading
● atypical activations in the left prefrontal regions, which are associated
with verbal working memory
● atypical activations in the left middle & superior temporal gyri, which
are associated with receptive language
● atypical activations in the left occipito-temporal regions, which are
associated with visual analysis of letters & words
● reduced activation in response to grating stimuli designed to
preferentially stimulate the magnocellular pathway in the visual cortex
● weaker white matter organisation in the left posterior region of the brain
● weaker connections in the primary reading pathway of the brain &
stronger connections between hemispheres, which may reflect an over
reliance on the right hemisphere regions for reading

It is thought that white matter tracts linking different areas of the brain are in
continuous interaction with each other during reading. Anatomical findings of
reduced integrity of these white matter tracts has been shown in
neuroimaging studies of adult dyslexics compared to adults with normal
reading ability (Vandermosten et al, 2012).

Question 20

The magnocellular deficit theory of dyslexia

Answer 20

The visual system has two parallel systems: the magnocellular (large-celled,
transient) system & the parvocellular (small-celled, sustained) system. The
magnocellular system responds to high temporal frequency & object
movement, & the parvocellular system responds to low-frequency & fine
spatial detail. The magnocellular system is important in reading. The
magnocellular deficit theory states that without the suppression of the
parvocellular system by the magnocellular system at the time of each
saccade, parvocellular activity from different fixations would be confused &
would result in a failure to keep separate neural activity elicited during
different fixations. Refer to ORT108 lectures
The difficulty in many areas of medical research is working out cause and
effect. Do the deficits in the magnocellular system cause the reading difficulty
or do they occur as a result of the reading difficulty? Olulade et al (2013)
provided evidence that visual magnocellular dysfunction does not cause
dyslexia, but instead occur as a consequence of poor reading ability. Opinions
still differ on the magnocellular system. Some do not accept it as a proven
theory for dyslexia (Handler et al, 2011), yet others believe testing individuals
at risk of ‘visually derived reading difficulties’ is important (Laycock et al,
2012).

Question 21

Treatment of dyslexia

Answer 21

Treatment of dyslexia isn’t considered to be a treatment of the underlying
condition, but is instead focuses on improving the weaknesses identified as
part of the condition. Dyslexic individuals are a heterogeneous group with a
different range of abilities and difficulties. A battery of tests is used to identify
each individual’s specific difficulties, so that their educational input can be
planned and individualised (McArthur et al, 2013). Teaching input is then
adapted to the individual’s weakness, i.e. additional help with reading &
teaching techniques altered to better suit the individual’s needs (for a detailed
description see Shaywitz et al, 2008). However, neuroimaging studies of
children who have been having active ‘treatment’ of their dyslexia show a
tendency towards ‘normalisation’ of brain activity following treatment,
highlighting that neural plasticity in children with dyslexia exists (Gabrieli,
2009). Overall, it is accepted that dyslexia is more receptive to treatment
when a child is younger, but older children can still gain benefits from
treatment (Shaywitz et al, 2008).
Much research has and is focussing on trying to identify or predict young
children at risk for dyslexia, so that they can receive specific and targeted
educational input at an earlier age. Rapid naming tasks are a strong predictor
for component reading skills in school age children, but young children are not
yet able to perform such tasks. The testing of young children is currently
exploring simple serial matching tasks that rely on processing speed. It is
hoped that specific cognitive skills may be prove to be strongly linked to the
skills required for reading (Park and Lombardino, 2013).
Early trial evidence that an educational intervention programme targeted at
adaptive coping strategies and environmental supports has shown promising
results in Australia (Firth et al, 2013). Further evidence about the impact of
educational input and other programmes is awaited before informed decisions
can be made about the most effective inputs for dyslexic children in
education.
Early evidence is also emerging that action video gaming in children can
improve attention and reading ability (Franceschini et al, 2013). Further
research exploring the impact of video gaming and improved attention on
reading is anticipated.
Phonics training for English-speaking poor readers has been shown to be
effective for improving some reading skills. Further research needs to be
designed robustly to ensure participants in the treatment and control groups,
as well as the examiners, are blind to the intervention. This will ensure the
effects measured are a treatment effect rather than a chance occurrence or
due to bias from study design (McArthur et al, 2012).

Question 22

Meares Irlen syndrome

Answer 22

Irlen Syndrome is a form of visual stress which leads to difficulties
with fine vision tasks such as reading. Helen Irlen first described this eye
condition in the 1980’s. It remains controversial however, as there are many
that don’t believe the condition exists or believe it is well defined enough for it
to be a recognised diagnosis (Handler et al, 2011) and of course there are
others that strongly believe it does exist (Northway, 2006).
For those that consider Meares-Irlen syndrome to exist, the condition is
described as affecting dyslexics and non-dyslexics. Like dyslexia, it is not
considered curable but can be treated, and improvements can be made
(Northway, 2012). For dyslexics, Meares – Irlen syndrome is sometimes said
to be the cause of reading difficulty.

Question 23

Meares Irlen symptoms

Answer 23

The symptoms will have been present throughout life but some people
experience symptoms after a minute of reading; others find the symptoms
take longer to appear. The degree of symptoms can also vary from person to
person with more marked symptoms creating barriers to successful reading.
Some will describe the symptoms as ‘visual stress’ & others may use the term
‘pattern glare’ (Evans et al, 1995).

Question 24

Meares Irlen problems

Answer 24

train working under bright lighting
● Difficulty finding comfortable lighting
BMedSci (Hons) Orthoptics
Year 2 – Gemma Arblaster
● Glare from bright objects
● Eye strain
● Headaches from reading, working at a computer, watching TV,
supermarket lighting
Symptoms resulting from reading may include:
● Poor comprehension
● Skips words or lines
● Reads slowly or hesitantly
● Loses place
● Headache
● Difficulty with crowding visual tasks
● Difficulty with tracking
● Eye strain
When reading they may see the words:
● Jumping off the page
● Spinning
● Moving around
● Blurring / going out of focus
● Not staying where they are supposed to
Symptoms judging distances may include:
● Clumsiness
● Accident prone
● Bumps into things
● Difficulty catching small balls

Question 25

Orthoptic findings in SLD patient

Answer 25

A higher incidence of binocular vision
abnormalities has been reported in children with reading & writing difficulties
(Dusek et al, 2010), although this is disputed by others (Handler et al, 2011;
Creavin et al, 2015). Others have reported a higher incidence of
accommodation and vergence problems in children with dyslexia (Raghuram
et al, 2018). Whatever the truth may be, it is important that BSV & ocular motility are
thoroughly investigated to ensure a problem, that may well be treatable, does
not go undiagnosed. Although vision problems can interfere with reading, it is
important to remember that vision problems are not the cause of dyslexia
(Handler et al, 2011).

Question 26

Orthoptic investigation in SLD patient

Answer 26

History
Visual acuity
Nr & Dist
PH if reduced
May retest with tinted lenses / coloured overlays if reduced (see later)
May include both crowded and uncrowded VA tests (see Gori and
Facoetti (2015) for a review article about crowding and dyslexia)
Refraction – may include dynamic retinoscopy (objective measurement of
accommodation)
Ocular examination – including a dilated fundus examination
Cover test
OM
To include assessment of saccades & smooth pursuit
May perform eye movement recordings
Note speed, accuracy, body position, body/head movements, initiation
Voluntary & involuntary saccadic control
Pro-saccades & anti-saccades
Smooth pursuit & ability to cross the midline
The developmental eye movement test: designed to detect errors of
vertical & horizontal scanning. The patient is timed reading subsets of
numbers & the results are analysed for horizontal & vertical tasks to
see if there are problems scanning or tracking (currently one in Eye
Movement Lab).
Conv
RAF rule
Repeated to assess fatigue
Smooth & Jump conv
Accommodation
RAF rule - binoc & monoc (subjective)
Dynamic retinoscopy (objective)
BSV (sensory & motor functions)
PCT
Reading fluency
Speed & accuracy
Eye movements made when reading
Types of mistakes made
Rate of reading test: (see below) series of random short words read
aloud, time taken recorded (currently one in JMR). Some may prefer to
assess reading fluency with a text rather than with random words.
Coloured overlay testing
Additional tests to quantitatively assess tracking behaviour, reading & visual
perception
Additional information about patient comfort when carrying out visual tasks
If necessary may also perform AC:A ratio, colour vision testing, visual field
testing
Diagnose presence or absence of Meares – Irlen syndrome
Fixation stability
Reference eye test
Used to determine which eye is being ‘referred to’ during binocular
vision: – use the Synoptophore with the foveal slides. Patient joins
slides whilst maintaining controls (subjective angle). Slowly diverge
tubes & ask patient which control moves. The control that remains
BMedSci (Hons) Orthoptics
Year 2 – Gemma Arblaster
stationary is in front of the reference eye. Repeated x10.
NB-this test is only valid before fusion breaks
Colorimetry
Visual perceptual skills – often hand-eye coordination tests are involved

Question 27

Orthoptic management of specific learning difficulties

Answer 27

Once a diagnosis is made a management plan can be made & implemented.
Treatments may be given in isolation or combined. The aim of treatment is to
achieve relief of visual symptoms that may contribute to reading or writing
difficulties. Treatment is not a cure for the condition itself.
This may include:
● Refractive correction
● Some patients with reading difficulty may also benefit from near
ADD
● Binocular vision treatment
● To treat a decompensating heterophoria
● Exercises to improve conv, accommodation or fusional reserves
(Dusek et al, 2011)
● Computer based horizontal vergences exercises – shown to
increase reading speed and +ve vergences in dyslexics with
‘normal BSV’. Dyslexics recruited from dyslexic school, but
compared to age matched controls. (Wahlberg Ramsay et al,
2014)
● Fusional vergence exercises may focus on foveal fusion range &
exercises on the Synoptophore
● Coloured overlays & tinted lenses
● In patients with Meares – Irlen syndrome
● Eye movement training
● Exercises to improve the speed & accuracy of eye movements
● Tracking exercises (Ann Arbor exercises)
● Visual perceptual training
● Often involving hand-eye coordination type exercises to improve
visual processing skills (Behavioural Optometry)
● Monocular occlusion
● In patients with poor fixation stability
● Less commonly used now compared to in the past
● Occlusion of one eye is advocated to remove confusion if the
reference eye is ‘unfixed’
The Orthoptist may also give advice on size of font in school, position in the
classroom, use of aids for keeping place on a line and reducing visual
confusion & fatigue, & would also consider onward referral to other
professionals.

Question 28

Treatment of Meares Irlen syndrome

Answer 28

There are a number of suggested treatments for Meares – Irlen syndrome and
different people may have different outcomes from treatment. Treatment for
Meares – Irlen does not cure the underlying condition, but aims to reduce
visual stress & improve the rate of reading. Treatment involves the use of
colour. Coloured overlays and glasses have been shown to lessen the effects
of visual stress. Treatment is highly specialised and needs to be set
specifically for the individual as the incorrect use of colour can worsen
symptoms.
● Use of cream or pastel coloured backgrounds
● Use of specific coloured text
● Coloured overlays
● Coloured filter glasses

Question 29

Coloured backgrounds and text

Answer 29

Coloured backgrounds & coloured text are assessed by asking the patient
what they subjectively prefer or find most comfortable. Reading or rate of
reading assessments can also be performed with and without each option to
try & quantify any improvements.
Coloured overlays are selected again by patient preference & by rate of
reading assessments with & without the overlay to quantify any changes in
reading speed & accuracy.

Question 30

Wilkins rate of reading test

Answer 30

The Wilkins rate of reading test is commonly used. It is not a measure
of cognitive ability. The patient reads the words on the page out loud &
the clinician records the time taken to read a number of words & the
number of errors made. The words are in a random order, i.e. it is not a
story that you could follow, & it is made up of simple words familiar to
children age 7 upwards. Different versions are available to prevent
patients learning the words by heart. A 5% increase in the score is
considered clinically significant.

Question 31

Intuitive overlays

Answer 31

Intuitive overlays are available from several different companies
claiming to be the best, but they are essentially all layers of coloured
plastic film that are placed over the page of text the patient is reading.
A wide range of coloured overlays should be shown to the patient to
ensure they have tried a large number of colours systematically.
Overlays can be given individually or one placed on top of another if
preferred. Investigations should be performed in standardised lighting
conditions.

Question 32

Colour filter glasses

Answer 32

Coloured filter glasses are selected specifically for the individual by the
clinician using an ‘intuitive colorimeter’.
The intuitive colorimeter aims to find the optimal precision tint that the
individual requires for the relief of their visual perceptual distortions as
part of their visual stress. The patient sits at the intuitive colorimeter &
selects which combination of colour best reduces or eliminates their
visual perception distortions. This would then be given to the patient to
wear as glasses or contact lenses. This is often used for the worst
affected individuals, i.e. coloured overlays are offered to all, but
coloured filter glasses are reserved for those thought to really need
them. The colour of the lens chosen is often not the same as the colour
chosen for an overlay. They are often expensive!

Question 33

Literature disagreements of colour filter glasses

Answer 33

Ray et al (2005) found an improvement in motion, accommodation,
convergence and reading in children age 7-14 when wearing yellow
filter glasses. However they only studied dyslexic children recruited
from a dyslexic clinic and had no control group or placebo.
Conway et al (2016) looked at whether gender influences colour choice
in the treatment of visual stress. Although this was not found for the
choice of coloured overlays, there was an association between gender
and choice of precision tinted lenses.
Razuk et al (2018) found that green filters improve reading
performance in children with dyslexia

Question 34

Controversy about colour filters and overlays

Answer 34

Coloured filters & overlays have therefore come under significant scientific
scrutiny because of the lack of high quality research evidence to support the
benefits claimed by the manufacturers.

Question 35

A review by Suttle et al (2018)

Answer 35

Concludes that the available evidence is not reliable to conclude that coloured filters are effective for alleviation of
reading difficulties/discomfort during reading. Therefore, coloured filters
should not be prescribed. However, as the filters will not cause harm to
patients (but cost to the health service) some clinicians may choose to
prescribe them for the placebo effect.

Question 36

Difficulty in orthoptic practise

Answer 36

There is such
disagreement in the literature about the true incidence of visual problems in
dyslexia, how they may be identified, how they should be described/classified
& how they should be treated.

Question 37

Orthoptists should

Answer 37

What is not in debate is the need for a detailed
orthoptic assessment, refraction & fundus & media check, to ensure the
patient doesn’t have an underlying abnormality of binocular vision, ocular
motility, or ocular health.
As clinicians we should remain open minded to new ideas and
theories that may benefit our patients, but we must also use our scientific
knowledge and critically evaluate the available evidence to inform our practice
and plan further robust studies.