When a child has complex medical needs or profound and multiple learning disabilities (PMLD) any concerns about visual responses need to be identified and given appropriate support at the earliest opportunity. Janet Harwood explains.

Early intervention can take full advantage of any potential for the child’s brain to develop and find different ways (sometimes called neural plasticity) to process sensory information and movement. Vision helps us to make sense of everything so every child needs the opportunity to develop their visual potential. Carefully structured support can make a huge difference to the ability of children who may not be able to make sense of what they “see” to engage with the world.

What to look for

You may notice some of these visual behaviours:

  • reaching for objects to the side but not straight ahead
  • looking away from people or objects in order to “see” them
  • vision which seems variable and may change on an hourly or day to day basis
  • For the mobile child – inaccurate visual guidance of movement and reach for objects
  • inability to look at objects for any length of time
  • irregular eye movements
  • lack of response to objects on a “busy” background that the child would respond to on a plain, contrasting surface
  • eye movements not made independently of head movements
  • difficulty seeing objects unless they are moving, or in other children, unless they are still
  • Lack of response to faces or facial expression.


Talk to people who know the child well about their observations of the child’s visual behaviours. This should include discussion with the child’s family, if possible in their home. Some children show more visual response at home surrounded by familiar objects which their brain has had repeated opportunities to recognise.

For the teacher of visually impaired children, observation is just as important as direct “work” with the child, to be sure to rule out responses to sound or smell or looking which may not be purposeful which others may have misinterpreted as accurate visual responses. Consider how different environments affect the child’s use of vision.

Key assessment questions:

  • At what distance do they respond to visual stimuli?
  • Contrast sensitivity is often poor even when acuity is good. At what distance, if at all, can they respond to faces?
  • Do they prefer or respond better to particular colours? If unsure, try “warm” colours such as red, orange or yellow as these are often responded to more readily.
  • How do they respond to large clear targets such as “Puppet Face” (see resources). This can be used to assess the line thickness that the child responds to and the visual fields.
  • Which quadrant does the child respond in, do they respond to targets in the central field of vision?
  • How long does it take to elicit a response?
  • What detail can be seen and responded to?

Important considerations

What is the optimum lighting?

Some children are very sensitive to light or glare, while some children with profound CVI respond better in low lighting conditions.


Objects in bold plain, preferred colours should always be used initially. Patterns are more difficult to process. Presenting an object against patterned clothing makes it harder to respond to. I carry a dark, plain T-shirt when working with children with complex needs. Work in a space that is quiet and uncluttered, as noise inevitably distracts the child.


What time of day is it? Is the child feeling tired or unwell? Are they as comfortable as possible and in a position where they can best view what you would like them to respond to. This is very important if a child has a visual field impairment or nystagmus, where they need to be able to use their “null point” to achieve their best possible vision. A child who is uncomfortable will not be able to put their efforts into visual attention.

Glasses and make up

Bright lipstick emphasises the mouth and eye makeup and glasses help some children to see your face more easily. You decide if this is an option for you! One child always reaches for my bold framed glasses and shows little interest when I am not wearing them. These factors may all influence a child’s ability to respond.

Time to respond

Focus on one object at a time. Give time for the child to respond and then more time. I have waited up to ten minutes but have been rewarded with a response, which if intervention had taken place, would have prevented the child from learning to use a touch screen programme. She can now respond quickly because she was given the initial time to process and learn what was needed.

Where are you presenting the object?

Consider the implications of visual field impairments especially if you are placing objects on trays attached to chairs. A child with a lower field impairment may not see items placed close by them on a tray, but may be able to see them propped up further back on the tray using a wedge, or if the tray is lifted until seen. Interpret responses carefully. Is the child really seeing the object on the tray or responding to someone moving in towards them from the front when they are placing it?

Apps to encourage or assess visual response

There are wonderful apps and technology to use but don’t be tempted to do too much at once. The best apps allow the speed and colours of any activity to be modified. Many children need a degree of movement to engage with a stimulus, but on screen it must be slow enough to give time to respond. You can readjust the speed once the child has seen the target or activity frequently and long enough to recognise it and respond more quickly. Find what motivates and repeat and repeat. You may find the repetition boring, but it allows the child’s brain to recognise, “see”, engage and learn!

Colour tents

Patient use of a colour tent may enable children who have the most profound cerebral visual impairment to respond. Teacher, Suzanne Little has worked extensively with colour tents with young people who have complex needs at Meldreth Manor School, a school for children with disabilities aged 6–19 run by national charity, Scope. The tents help learners to block out all distraction and begin to engage with their world. “ Each child with CVI needs a structured, individual approach”

We have worked with a child in Brighton who was showing extremely limited responses. Now when placed comfortably under her preferred fabric she is beginning to respond and interact, reaching up to the tent above her and vocalising happily.

Large pieces of lining fabric, some fluorescent are very portable and can be cheaply bought via eBay. For young children or babies, a small pop up tent can work just as well, if pattern is eliminated by tacking on plain fabric. Success may take many sessions and all the factors which may affect visual response, need to be considered.

Each child with CVI needs a structured, individual approach. Painstakingly taking account of the factors that may affect their responses will help them to achieve their visual potential. By understanding more about how the visual system works and changing mainstream perception of “vision”, we can help to transform the lives of those affected by CVI and their families.

Janet Harwood is a qualified teacher of visually impaired children for Brighton and Hove Sensory Needs Service


Meldreth Manor School 

Find out more about Meldreth Manor School on the Meldrith Manor School website

Puppet faces

Puppet faces are six hand-held puppets that can be twirled between finger and thumb. They are not toys and should be used by adults to assess visual awareness and a baseline indication of field of vision. The back of the puppet is not easily seen against a dark background but it “pops” into view when twirled round. Another half twirl and it disappears again! Available from Beesneez

Visual assessment and vision stimulation apps 

A huge number of apps are available, many for free, but one size doesn’t fit all. Remember that for children with CVI “less is more”.

Explore some of the options on the Inclusive Technology website and the Wonder Baby website.


For RNIB’s guidance on assessment, communication and working with children who have complex needs visit the Guidance on teaching an learning section.

For more information about cerebral vision impairment visit the CVI Society website.