Problems Experienced by Children with Cognitive Visual Dysfunction Due to
Cerebral Visual Impairment – and the Approaches which Parents Have Adopted
to Deal with these Problems.
Elisabeth C.A. McKillop2,3* David Bennett1, Gillian McDaid3, Barbara Holland3,
Garth Smith3, Katherine Spowart3, Gordon N Dutton1,2,3.
1. Department of Vision Sciences
Glasgow Caledonian University
Cowcaddens Road
Glasgow G4 0BA
Scotland UK
2. Tennent Institute of Ophthalmology, Gartnavel General Hospital
Great Western Road
Glasgow G12 0YN
Tel: 0141 211 2937 Fax: 0141 211 6290
E-mail: Sheena.MacKay@NorthGlasgow.scot.nhs.uk
3. The Royal Hospital for Sick Children, Yorkhill
Glasgow G3 8SJ
Tel: 0141 201 0818 Fax: 0141 201 0858
E mail: Claire.Condron@yorkhill.scot.nhs.uk
Running Title: Cognitive Visual Dysfunction in Children
Key words:
*Corresponding
author
Abstract
Damage to the brain in children results in a multiplicity of visual difficulties which
have to be managed both at home and at school. Parents of such children have
detailed knowledge about the nature and characteristics of their child’s visual
difficulties and develop a range of coping strategies, often without realising they have
done so. We invited the parents of children with such problems to a meeting in which
they were encouraged to share their experiences with each other. This paper provides
a detailed account of the approaches which the parents described as being helpful in
the day to day care of their children.
Introduction
The brain plays a major role in carrying out visual tasks. (Grusser & Landis 1991;
Dutton 2003; Goodale & Milner 2004; Milner & Goodale 1995; Stashef & Barton
2001; Trobe & Bauer 1986) It is not surprising that brain damage can lead to visual
problems. A clear distinction exists between disorders due to impaired visual input
and those due to impaired processing of visual information. We have a relatively good
understanding of the simple aspects of vision, however, the nature and development
of higher visual function is less well understood. Brain damage can result in impaired
processing of visual information. The type of visual impairment in affected children is
wide ranging and variable. Problems can occur with recognition, orientation, using
vision to plan motion, the ability to see something when there is a lot of background
pattern and the ability to see things which are moving or when the child is moving.
Eliciting these problems in a classical consultation is difficult due to time constraints,
the poor attention span of children and the variability of these symptoms. Detailed
history taking is required to encourage parents to report the problems that these
children have. (Houliston, Taguri & Dutton 2000) The information that parents
provide allows us to develop our understanding of cerebral visual impairment (CVI).
CVI can cause many problems, which may diminish with age. Children with CVI and
their parents have to live with these problems every day and as a result develop many
coping strategies. We identified children with probable CVI and invited their parents
to a discussion group to share their experiences of the problems and to discuss
possible solutions.
The aims of this exercise were to:
1. Assemble a set of information to broaden our current knowledge of the ways
families deal with the difficulties that children with CVI have, and to use this
knowledge both to inform our future questioning strategies and to improve the
advice that we provide.
2. Extend our current knowledge of the strategies that parents have found helpful
for children with cerebral visual impairment.
3. Help the parents and their children both by attending the meeting and by
receiving the key data in this report.
Method
Increasing awareness of the problem of CVI within our department has led to over 40
children with evidence of CVI related symptoms being identified during the last year
by means of careful structured history taking in ‘at risk’ children. The parents,
grandparents and carers of these children were invited to a discussion afternoon. Over
40 people who look after 17 children attended.
After an initial tutorial about how damage to the brain can alter the way children see
and understand the world around them, the parents divided into four groups and were
encouraged to share their experiences of the problems they felt their children
encountered on a day to day basis. They were asked to describe the strategies they had
developed to help their children. Each small group was chaired by a staff member,
who made detailed contemporaneous notes. These notes were appraised in detail and
were employed to derive the following information.
Results
Parents reported numerous different problems. They explained solutions that they had
found to these problems and difficulties they had encountered. They talked about the
social problems CVI can cause and provided support and advice to each other. No two
children shared exactly the same problems, however many of the parents had had
similar experiences and shared similar stories. They reported variable impairment of
clarity of vision, colour vision, contrast perception, field of vision, movement
detection or visual memory and problems with crowding, complexity, visual fatigue,
recognition, orientation and mobility in the three dimensional world. These problems
had many social consequences.
Clarity of vision
Visual acuity or clarity of vision is an easily recordable aspect of visual function,
however it is not a measure of functional vision. Some parents reported children with
good visual acuity while others did not. Children’s clarity of vision appeared to the
parents, to be variable, and was impaired by tiredness. Best central visual function
was described as being only sustainable for short periods of time. Parents reported
that text could be read at a better speed and for longer if the size was increased. They
emphasised the importance of recognising this when teaching the child to read. There
was a consensus that educational material needs to be set within the limits of each
child’s ‘functional visual acuity’.
Colour and contrast
Brain damage can affect colour and contrast perception to a varying degree although
often the impairment is mild. Some parents did report problems with this aspect of
vision. They emphasised the importance of making toys and educational material
bright and clear. Children prefer to look at pictures with distinct colour boundaries. It
was important to avoid poor contrast, such as grey text against grey background, as
this was described as impairing educational value, enjoyment and attainment.
Visual fields
Children with CVI can have a variety of associated visual field deficits, which add to
overall visual impairment.
Hemianopia
Hemianopia comprises lack of vision on one side or the other. Damage to the right
side of the brain can give rise to lack of vision on the opposite side. The lack of vision
is identical for each eye. The children with hemianopia had problems when eating.
They often leave food on one side of the plate and the plate needs to be turned round
for the children to eat everything. Exploration outwith their visual field was
encouraged by placing favourite food on the hemianopic side. One child had a
tendency to push food off one side of the plate. The use of a bowl to hold the food or
a receptacle under the plate proved helpful.
Reading and access to information is restricted by hemianopia. Information on one
side of the page is missed. Right hemianopia causes each new word to jump into view
and may not be anticipated when looking straight ahead. Parents reported difficulties
for the children in finding the next word when reading. Using a finger to trace the text
was a solution. Some had found the use of a dome magnifier or CCTV to magnify the
text useful.
Left hemianopia means the text to the left progressively disappears when reading, so
finding the beginning of the next line is problematic. It was important to show the
child where to start and encourage them to move a finger down the left hand margin
to keep the place. Again magnification was useful.
Reading text vertically or obliquely was reported as helpful in hemianopia. Some
children had independently discovered that reading vertically downwards for right
hemianopia and reading vertically upwards for left hemianopia significantly improved
reading speed and comprehension.
Similar problems occur with writing, as these children often lose their place. Parents
reported children lift the pen off the page to check where it is and then try again, but
find this time consuming and frustrating. Using a guide such as a ruler to allow
consecutive writing along a line was found to prove helpful for some children.
Hemianopia causes significant communication problems, as the child does not see
people sitting or approaching from the affected side. Awareness of this at home and in
school was essential. The seating position in the classroom needs careful selection in
order to maintain attention in the subject of interest. Children with left hemianopia
need to sit with the teacher slightly to their right and those with right hemianopia need
to sit with the teacher slightly to the left.
Mobility was affected by hemianopia with children bumping into doorways or
obstacles on the affected side. Careful guidance around a new environment was
essential. Care had to be taken not to move things around the home or school without
involving the child. It was felt that allowing the child to explore a new environment,
to learn where the obstacles are located can prove very helpful. When children go to
parties it was found that it is a good idea for the child to arrive early to explore the
venue in advance and to allow the number of people present to gradually build up,
rather than going straight into a crowded room.
Great care had to be taken when crossing roads as traffic on one side was missed,
especially if it was silent like a bicycle. This problem was particularly marked for
children who also have difficulty the perception of moving objects. Affected children
need to be educated about the danger and to be taught to fully turn their heads when
looking for traffic. Teaching by example was felt best and the use of pedestrian
crossings, especially with speech guidance was encouraged.
Lower visual field impairment
Some children have lower visual field loss causing mobility problems. To move over
irregular ground they have to be taught to look down regularly to check the ground
ahead. One child had found great freedom from horse riding allowing mobility over
rough ground, as well as helping balance training. Similar problems to hemianopia
were encountered when eating. A number of children were found to be helped by
wheeling a wheeled toy like a pram in front of them as this provides a guide for the
child as to the height of the ground ahead.
Visual Field Constriction
This is unusual in children with CVI although it was related as a problem by some
parents. This may in fact have been apparent visual field constriction due to difficulty
in attending to a lot of information at once. It appeared that if the visual scene was
made less complicated apparent lack of attention in the peripheral field disappeared.
Central Visual Field Impairment
This was felt to be an issue in some children. The peripheral visual field continued to
provide valuable information. Some parents reported that their child appeared to look
past objects of interest, or the person they were talking to because they appeared to
choose a head position to give them the clearest picture. Teachers had to be educated
regarding this to understand that the child was not losing attention in the subject of
interest, but in fact may be concentrating intently despite appearing not to be
‘looking’.
Seeing Movement
Children with CVI may suffer from impaired tracking ability and impaired movement
perception. Impaired tracking causes problems with following a moving target. This
can be compensated for, by movement of the head. However, this only works if the
object is moving slowly. Impaired tracking affected the ability to learn to read due to
inaccurate movement along the text. Children were described as missing words which
appear to jump around the text making reading slow and difficult. Using a finger to
keep the place helped, as did enlarging the print size.
Impaired movement perception means that children can see static objects but not
moving ones, or only very slowly moving ones. Some parents reported that their child
chose to watch television programs with limited movement, such as the weather man
or news, instead of cartoons with rapid movement. Some children became frightened
by sudden movement. It was important to educate those teaching the child to use slow
movements and gestures. It was suggested that educational material like video and
DVD tend not to be useful in these children. A major issue for all parents of these
children was that they did not easily see traffic, and if they can see traffic it is difficult
to estimate its speed. All parents felt the child needed a guide in this situation for
safety reasons.
Visual Memory
Children with CVI have problems with visual memory. Children were described as
having problems copying text or figures, despite being able to identify them. Parents
suggested verbal memory was better than visual in some children. To improve tasks
such as copying they encouraged their child to initially speak out loud what they had
to copy to form auditory memories. With practice the child could then learn to use
their auditory memory to improve copying skills.
Crowding and Complexity
Many children with CVI have problems with simultaneous visual processing, finding
it hard to cope with a lot of visual information at once. This led to many different
issues.
Meal times were a problem. Children would not eat food that was mixed together.
Parents recommended separate food portions with a reasonable gap between them.
They also suggested avoiding sauce or gravy as this blended the foods together, which
prevented them being seen as being separate. One child would not eat off a patterned
plate.
Some children experienced problems locating toys on patterned backgrounds such as
a carpet or a bed spread. A favourite toy was also harder to locate if mixed in with
others. Storing favourite toys separately, and playing with a small number of toys on a
plain background were recommended.
Reading was affected when the letter size was small and the words close together in
large blocks of text. To aid reading text should be broken down into small parts and
presented sequentially. Widening the gap between words helped some children, as did
covering words as they were read. Double spacing of printed text is very helpful.
Computers were used to allow one word to be presented at a time from the body of
the text. In those less severely affected, enlargement of text was found to be helpful
because it decreased the crowding of the letters and the words and magnifiers were
suggested. One child had gained this magnification with correction for long
sightedness.
Some parents found that their child could not look and listen at the same time, often
turning away if someone was speaking to them, allowing them to concentrate better
on what was being said. Children had been inappropriately scolded for this at school
as it appeared rude.
Complex tasks were highlighted as difficult for some. Tasks should be broken into
stages and built up gradually and sequentially, as the child will withdraw if forced to
do something too fast. One child had a notebook at school so the teacher could write
down what to do next so she did not have to keep being reminded.
These children often found busy environments problematic or frightening. Some did
not like the cinema, several parents reported three-dimensional movies had caused
distress. The importance of a clutter free environment at home and school was
emphasised.
Parents reported their child appeared not to hear instructions if asked to do something
when concentrating on another task, such as watching television. To communicate
properly the television had to be turned off or a favourite toy removed. Reduction in
background noise also helped.
There were different ways suggested to get attention. A clap or recognisable sound
was used to alert the child to obstacles ahead. (Telling a child about an imminent
obstacle does not help as this causes too much distraction.) Tactile stimulation such as
a tap on the shoulder was better for some.
The importance of praising the child for keeping attention was recognised. Group
instructions were sometimes ignored and the child needed one to one instruction to
aid understanding. Apparent inattention was worse in busy, noisy environments.
Visual Fatigue
The processing of visual information is often prolonged in these children. Detailed
inspection involves tremendous mental effort especially for those with limited vision.
Children with CVI often develop problems when tired. It was important for parents
and teachers to understand why the child had periods of apparent good vision and then
periods when it was much less good.
Fatigue could be minimised by removing clutter and enlarging text. Everyone
working with the child had to be aware of the need to reduce the amount of
information the child was presented with, the detail and complexity of this and the
speed they were expected to work at. This reduced the number of inattentive periods.
Well earned breaks were essential. Some children were encouraged to take work that
they could not finish at school home, rather than being seen to be slower than
everyone else. A period of relaxation after school was needed before doing
homework. At school ‘quiet time’ was used when the child got distracted. To help
this the ‘Naughty Table’ was renamed the ‘Quiet Table’ for some children, where it
was found performance improved considerably.
Some children became easily fatigued at birthday parties. It was important to teach the
child a way of extracting themselves from difficult situations to find a quiet place to
recover.
Recognition
Children with CVI seem to have problems knowing and understanding what they see.
They can have problems identifying people, shapes and objects
Recognition of people
Some are unable to recognise faces particularly in a crowd. This was a problem at
school and when out shopping. Some parents helped their child identify them by
always wearing the same bright item of clothing or standing in the same place when
meeting them after school. Auditory identification by calling their name helped.
Teachers had to make themselves easily identifiable in a similar way.
An inability to read facial expression was described. This impaired social interaction.
Recognition of people and the meaning of what was said were conveyed better by the
tone of voice. It was found that when teachers explained to the class of young children
that the child with CVI had poor vision and that was why he could not identify
friends, the information was taken on board very well and acted upon appropriately by
the classmates.
Recognition of shape and form
There were problems recognising shapes, objects and animals. This compounded
reading difficulties. To learn animal names one child had started with a photograph
and the name, then learned the noise. The information had to be constantly reinforced
and was aided by going to see each animal live. Learning to recognise shapes and
objects was a slow process with constant encouragement and reinforcement required.
Reading had been helped in one case by a reading buddy who took the child out of
class each day for one to one tuition.
Orientation
Orientation difficulties are common in children with CVI. This includes problems
moving from one location to another and impaired ability to find objects when they
are stored away.
Orientation outside
Many parents report that their child has difficulty finding their way from one place to
another, even when they regularly travel the route. This was compounded by rarely
being allowed out alone. Some tried to encourage the child to take the lead when out
together. Talking about important routes in a consistent manner helped reinforcement.
Some children managed to navigate outside on their own by looking out for important
landmarks. Several parents had incorporated these landmarks into a poem or song
which the child could repeat to themselves as they travelled.
Playing hide and seek and getting out regularly seemed to help. One family had made
video recordings of outings and replayed them to the child to act as reinforcement
Orientation inside
Similar navigation problems were experienced inside, even within the house or a
familiar place, such as school. Again identifiers were important with mnemonics to
help memory. Allowing the child to act as a messenger in school aided exploration.
Having a friend to help guide the child to the correct place worked well for some. For
others a teacher or assistant was required to take them around the school.
Orientation around new places
Children had problems the first time they visited somewhere. Many parents suggested
going to somewhere new, such as the supermarket, when it was very quiet. Once the
child learned the layout of the new place they were more comfortable to go when it
was busy. This also applied to play parks, swimming baths and cinemas.
Some children found visiting friends’ houses and birthday parties especially difficult
as they were in new surroundings with other children distracting them, moving toys,
talking and touching them. One family routinely took their child to the location of a
birthday party a few days before, when it was quiet, to help them feel more
comfortable.
Holidays were problematic with difficulty navigating around hotel corridors impairing
their independence. Teaching routes with key targets again was important. Some
parents felt allowing the child to explore an area once it was safe was best.
Locating objects.
Some children had problems locating objects, often searching for things and making a
mess. This had been misinterpreted as a behavioural problem. Strategies, such as
mnemonics or rhymes, to remember where things were stored were used. Organised
storage was essential.
Many children could not locate items in a pile or in a cluttered area. Storage had to be
clearly labelled and items always kept in the same place. Words, logos and colour
coding were all recommended as identifiers. One child had gained independence in
dressing by having his clothes stored on colour coded hangers to tell him which were
play clothes and which were smart clothes. A shoe rack was recommended, as were
designated drawers for each item of clothing so a child knew exactly where
everything was and where to leave things. Favourite toys should always be stored in
the same place so they can be easily located.
Children often preferred having the same seat and the same setting of table at home
and school. A dedicated workstation at school, laid out in a set manner was useful.
Many parents emphasised how important it was to involve the child in decisions to
move things and tell them if their normal routine was going to change.
Moving through the 3D world
Children with CVI can have profound problems with depth perception and bringing
about accurate movements through visual space. This can affect their legs or arms or
both and can of course be compounded by weakness or spasticity. Mobility was aided
by minimising distraction such as background noise from talking.
Some had problems distinguishing a line on the ground from a step and commonly
explored boundaries such as that between lino and carpet. Problems occurred with
steps and kerbs, which were often tripped over. Some reported going upstairs was
easier than down due to problems in estimating the depth of each step. A short
warning noise when approaching a step or obstacle was useful and less distracting
than a spoken warning. Marking the stairs with a bright edge and using a guide rail
was recommended. Holding onto a parent’s hand, elbow or trousers was essential for
some in order to afford tactile guidance as to the height of the ground ahead.
Walking over things and bumping into obstacles was a big problem, compounded by
visual field defects. Guidance around a new environment helped.
Limiting the
number of toys out at any time was useful, as was the use a play mat to define a space
that the toys are present in and provide a boundary for keeping toys contained within.
Gates and barriers were suggested to prevent children bumping into things, but this
was also a cause of frustration. Younger children were often bumped into. Some
children found the use of a tactile guide placed in front of them helpful. A white stick
carried too much stigma, but using objects such as wheeled measuring sticks, prams,
scooters or bikes was promoted.
Coordination and mobility was improved by activities such as tap dancing, martial
arts, swimming and gymnastics. Quiet soft play areas were invaluable to teach
movement through 3D space without injury.
Some had problems reaching for and manipulating objects. This was difficult to
distinguish from problems due to weakness or poor coordination. Typically the reach
was intermittently inaccurate. Repeated practice did improve this.
Social Problems
All parents emphasised how socially debilitating these problems are, even in the more
mildly affected children. The importance of communication with those in regular
contact with the child was essential to share coping strategies.
At school it is important that all teachers are well informed. The children were often
labelled as naughty or disruptive due to lack of understanding on the part of the
teachers. Some schools had been very supportive, others less so. Parents felt a definite
medical diagnosis would help this, but were also cautious about labelling their child.
The children often required extra equipment at school and a special locker was useful
to store this, so the child was less self conscious. Attempts to include the child in all
activities are important and this requires adjustments to teaching style. Allowing the
child to partake in discussions and answer questions in class is important even if it
takes time
Identifying problems and encouraging the child to overcome them is essential.
Constant reassurance is important. Several parents helped their child with difficult
situations by making up stories where a hero had a similar problem and managed to
find a solution. Visualisation was used as a technique to overcome problems by some.
Parents helped children by identifying specific tasks they could not do and repeatedly
practicing them to avoid self consciousness. This varied from using scissors to
playing party games.
Finding something the child could excel at was helpful and boosted confidence. Many
children found comfort within a well known peer group but excluded themselves
when they felt uncomfortable in larger groups. Some enjoyed team games while
others did not. It was important to find activities the child enjoyed and promote these.
Summary
Cerebral visual impairment is a poorly understood condition, which encompasses a
wide range of problems. Our children were identified from a paediatric
ophthalmology clinic as those having symptoms from impaired processing of visual
information. This caused varying problems with clarity of vision, colour vision,
contrast perception, field of vision, movement detection, visual memory, crowding,
dealing with complex visual scenes, visual fatigue, recognition, orientation and
mobility in the three dimensional world. Every child exhibited a range of these
problems to a varying degree and many of the problems diminished with age, but all
had associated social problems. The parents of these children had many coping
strategies to improve their child’s everyday life. The parents all agreed that the
discussion had been very helpful. They found it reassuring to hear of other families
with the same problems and helpful to share coping strategies. They felt that support
groups for families of children with CVI would be useful and suggested improved
access to information and resources for their children.
There is still much to be learned about CVI, but this session with parents provided a
great deal of insight into the range of symptoms that these children might exhibit.
More importantly, for those involved in their care, it highlighted the daily problems
these children experience and some strategies to overcome these.
Acknowledgement: Cerebra has provided funding which supported this work
References.
Dutton GN. Visual problems in children with damage to the brain. Visual Impairment
Research 2003; 2: 384-9.
Goodale M, Milner D. Sight Unseen. Oxford University Press: Oxford 2004.
Grusser O-J, Landis T. (1991) Volume 12. Visual agnosias and other disturbances of
visual perception and cognition. In: Cronly Dillon JR (ed) Vision and Visual
Dysfunction. Macmillan Press. London.
Houliston MJ, Taguri AH, Dutton GN. Evidence of cognitive visual problems in
children with hydrocephalus: a structured clinical history-taking strategy. Devel Med
Child Neurol 2000; 42: 298-306.
Milner AD, Goodale MA. The visual brain in action. Oxford University Press:
Oxford 1995.
Stasheff SF, Barton JJ. Deficits in cortical visual function.
Ophthalmol Clin North Am 2001; 14: 217-242.
Trobe JR, Bauer RM. Seeing but not recognizing. Surv Ophthalmol 1986; 30: 328336.