Visual difficulties often go undetected in children with SEN, but much can be done to support the vision of those with even complex conditions
How we see the world around us is a fundamental part of how we live and respond to our environment. Approximately 40 per cent of the brain is devoted to processing visual information and how we see directly impacts on how we learn. Good vision is something we can often take for granted.
Children with SEN are much more likely to have visual problems and are more likely to require eyecare treatment and wear spectacles. The UK Vision 2020 Strategy recently reported that people with learning disabilities are ten times more likely to have a sight problem. Having a severe or profound learning disability substantially increases the risk of visual impairment and blindness. However, children with SEN often have other, perhaps more urgent health issues, so understandably the assessment of vision is not always given priority.
One recent study assessed the vision of over 1,300 people with a learning disability and reported previously unknown visual problems in over 40 per cent of the group (van Splunder et al., 2006).
Visual impairment can be described in many ways, including sight loss, partial sight, low vision, and blindness. It is very rare that anyone is truly blind, in that most people see something, even if it is only to distinguish light and dark. In education, it is customary to discuss sight problems in terms of sensory impairment. This is then divided into two categories: severely sight impaired and sight impaired, which are often referred to as “blind” and “partially sighted”. These terms have a medical definition and the World Health Organisation defines “Sight impaired (partial sight)” as a visual acuity score of less than 6/18 and “Severely sight impaired (Blind)” as a visual acuity score of less than 3/60. A person whose visual acuity meets these criteria may be registered as having partial sight or blindness by an ophthalmologist. In addition, significant visual field loss (a restriction in the extent of peripheral vision) may also mean that someone is registered blind or partially sighted.
Whilst registration can bring benefits, registration of a visual impairment is not mandatory and it sometimes doesn’t happen because of anticipated stigma or an uncertain prognosis. Furthermore, children with SEN, where other conditions are the primary concern, may never have visual impairment formerly registered, or even identified.
Importance of vision in those with SEN
Even if a child does not have the label of partially sighted or blind, there may still be significant problems with vision, and knowledge of what a child sees (and doesn’t see) is highly relevant to the daily life of the child and to teachers working with children with SEN. Knowledge about visual ability and limitations allows for the provision of visual material of the appropriate size, detail and contrast at a suitable distance. Furthermore, children with neurological impairments are more likely to have or require spectacles; understanding the importance of spectacles and when they should be used is invaluable to the daily living of the child.
Some children with neurological impairment may have restrictions in the extent of their peripheral vision. We are normally aware of objects and our environment at the edge of our vision: out to our sides and above and below us. This is very important to us as we move through our environment and are aware of obstacles. If a child has problems seeing all around them, this could impact on their mobility and orientation skills.
Some people think it is not possible to test the vision of a child with SEN if the child cannot read letters. However, there are several ways to examine vision and get a measurement of what a child sees that don’t involve complex instructions or verbal responses from a child. These include using pictures instead of letters, using a matching card for non-verbal communication or assessing the eye movements of a child to see what they are looking at. The need for glasses can also be assessed with only minimal cooperation from the child. Careful assessment of head posture, their attention to moving targets, and ability to follow a target also gives useful information about the child’s vision and visual function. In addition, prior to assessment, discussion with the parent and teacher can give useful information about the child’s visual habits and medical history.
Ben has cerebral palsy and uses a wheelchair. He was seven years old when he had his first visual assessment. He had very poor head posture and was slumped over in his chair so that he was gazing down into his lap. His Mum and teachers all had to kneel on the floor and look up into Ben’s face to get his attention and had to put things into Ben’s lap to get him to pay attention to them. Ben was scared of loud noises and didn’t like people approaching him from behind. When Ben’s eyes were checked, he had a significant need for glasses as he was very short sighted. Without any glasses, he had very poor vision except when things were held very close. Ben was given glasses and there was a great improvement in his posture. Now, Ben sits up straight in his chair and holds his head up. His vision is much better with his glasses on, and he is much more visually attentive and engages with objects and people.
Clarity of vision
Visual acuity is a measure of the detail the eyes can see. When someone has poorer vision than normal, they may find it difficult to recognise small objects unless they are close to them. Children with SEN and young children often hold things close to their eyes or watch TV at a close distance. Sometimes, doing things at a close distance is a sign of visual difficulties, although some children just enjoy the extra sensory stimulation they get from being close to the TV.
Many children with SEN require glasses, often strongly powered glasses. Glasses contain lenses which, when placed in front of the eye, restore the eye to an appropriate power for clear distance viewing. Wearing the right glasses will make sure visual acuity is as good as it can be and is an important part of optimising vision and visual development. If the need for glasses is detected early in the child’s life, visual development can be maximised and is likely to have a positive impact on the visual outcome for that child.
Children with neurological impairment may have glasses that are required all the time, or just for close or distant tasks. It is important that glasses are comfortable and fit the child well so they are looking through them appropriately. Some people report that children with SEN may take their glasses off sometimes (even when vision is much better with them) because they want to take a break from processing the clearer picture as their blurred image (without their glasses) is less complex.
Cassie is a five-year-old girl with Down syndrome. Her mum reported that Cassie has difficulties in unfamiliar places and that Cassie doesn’t see her sister or dad coming towards her in a crowded supermarket. She also doesn’t seem to respond to what her mum points at when they are out together. She has glasses and her mum knows she sees much better with them. At home, she is keen to look at picture books and likes drawing but she doesn’t really engage with many TV programs, although she does watch when fairly static images are shown, such as people speaking on screen.
Cassie was visually assessed and was found to have difficulty seeing things of low contrast. Her mum was advised that Cassie struggles to process more complicated visual scenes and needs things presented more simply with less clutter. She finds it hard to process movement in her environment and she needs things to be bright and bold to see them well. Her mum was given examples of the minimum size of picture/writing Cassie can see, and was advised to present objects on a plain background and use heavy lined pictures and pages for Cassie to colour in or write on. Cassie should also use dark thick pencils so that she can clearly see what she is drawing/writing.
Contrast and colour
Contrast describes the balance between the dark and light parts of an image. Neurological problems may affect how contrast and colour is seen, so children with SEN should have bright and bold toys and other materials. It is important to avoid poor contrast, such as grey text on a dull coloured background and any photocopied material should be checked to ensure the text isn’t faded. Having clear boundaries on the edge of the workspace is useful. If a child is writing, heavily ruled paper can be useful for the child to see the lines clearly. The use of dark, thick pencils makes sure the child can see what s/he is writing.
Crowding and complexity
Many children with SEN will have problems with visual processing, and find it hard to cope with a lot of visual information at once. The process of seeing involves the eyes sending the visual information they acquire to the brain; the brain then processes the image and tries to understand the important things in the image using visual memory and discrimination. However, this process is demanding and can be delayed or overwhelmed by complex information, slowing the process down. Children with difficulties with visual processing can be overwhelmed with extraneous visual information and demonstrate a reduction in visual performance or decreased attention or cooperation. Things should be kept simple and free from clutter, and backgrounds should be plain so the child can see objects, such as their toy, easily. Children may need more time to look at an object. Looking and listening at the same time may be difficult, so some children may appear to be looking away from someone talking but they are actually trying to avoid getting extra visual information and concentrate on listening.
Interpreting the visual environment can take a lot of mental effort for children with neurological impairment, so it may appear that vision is worse at some times, or on some days, than others. If a child is tired, unwell or under pressure, this may impact negatively on visual performance.
If there is a concern about vision, or a child hasn’t had a visual assessment in some time, parents/carers should be encouraged to arrange an assessment.
Whether detailed knowledge of the child’s vision is known or not, there are things we can consider in the classroom and at home to maximise the visual and learning experience of the child. These include:
- if a child wears glasses, understand whether they should have them on all the time or not and make sure they are kept clean and fitted appropriately
- make educational/recreational material bright, bold and clear, use larger print and good contrast and ensure lighting in the room is bright, using natural light where possible. Glare can be a problem so adjusting blinds or curtains to minimise this may be necessary
- avoid crowding and complexity with tasks. Avoid overwhelming the child with too many objects or too much material at one time. This could mean covering part of the work, or ensuring an object you want them to locate stands out from the background. Finger pointing or using a ruler may help a child navigate work more easily
- ensure the child has enough time to process visual information. Letting the child reach and feel an object may also help them visually process the object
- when placing a child in a classroom, consider their behaviour and how they like to work. If they have a visual field problem, place them so their view of the room is on their unaffected side. In group situations, try to ensure they do not need to turn their head too much to take part
- if finding work items is a problem, try and ensure they are kept in the same place, and that the layout of the room is not suddenly changed.
Children with SEN are significantly more likely to have visual problems, even when a child is not registered as being blind or partially sighted. Many children with SEN require glasses and these often need to be a strong power. They also more commonly have visual field problems and visual processing is likely to be slower.
Knowledge of the child’s vision is fundamental to how they learn and interpret their environment around them. Detailed visual assessment and feedback on functional vision is invaluable to all the people involved in the child’s care and daily life.
Dr Julie-Anne Little is a Lecturer in Optometry at the University of Ulster and has a special interest in learning disabled paediatric populations. She is currently working on a project, funded by the Research and Development Office of Northern Ireland, to disseminate knowledge about vision in complex neurological impairment to professionals and parents. http://biomed.science.ulster.ac.uk/vision/-Paediatric-Research-.html
Information for carers about getting eye tests for people with learning disabilities can be found at: www.lookupinfo.org/carers_supporters