What Cerebral Visual Impairment (CVI) is, what pupils with CVI might have problems with and how to help them, CVI and complex needs.
Cerebral Visual Impairment (CVI) is a form of visual impairment caused by the brain not being able to process information from the eyes passing along the visual pathways in the brain. As the pupil grows older, the visual difficulties may slowly improve as they find strategies to use their vision.
What pupils with CVI might have problems with
Pupils with CVI can have problems with:
- recognising faces
- recognising and reaching for objects
- clarity of vision, that is sharpness of vision for both near and distance vision
- seeing movement
- visual field loss, also known as peripheral vision loss
- colour and contrast
- crowding and complexity, for example difficulty seeing detail or one item in a busy scene
- visual fatigue, for example pupils may have periods of good vision and then periods when vision is less good
- controlling eye movements
- moving through the world, for example using stairs, steps and slopes
- orientation and route finding, for example losing their way even in familiar places
How to help pupils with CVI
Some strategies that may be useful:
- pupils who have difficulties in recognizing faces use an identifier, for example always wearing the same coloured item, having a meeting point in the playground, or a buddy
- reducing visual clutter, visually simple and of good contrast
- enlarging print size and increasing the space between words on a line
- using a desk slope bring the text closer and keeps it in central visual field
- using a typoscope (a small window cut into a piece of card) to isolate words and help prevent crowding
- using a child’s preferred colour to engage in activities (red is often preferred)
- avoiding visual clutter in the general environment by keeping storage and signage simple, for example using the end peg or the end drawer for the pupil’s storage
- making sure a pupil is seated appropriately so they can concentrate on seeing, for example at the front of the class
- practicing key routes and using highlight landmarks
- highlighting obstacles, steps and stairs
- keeping objects in the same place to help location, for example coat peg, seating, equipment
CVI and pupils with complex needs
There are a range of characteristics often present in pupils with CVI and complex needs. Being aware of these characteristics can be helpful in setting up invention programmes.
Many pupils with CVI have a colour preference, often red or yellow. This can be used in the resources used to encourage visual attention before introducing 2 or 3 colours and patterns.
Need for movement
Pupils with CVI start by being visually attracted by movement or reflective properties to initiate visual attention. The need for movement may reduce.
Pupils with CVI often need time to make a visual response and to interpret what they see. The time to respond will reduce as visual targets become familiar.
Visual field preference
Pupils with CVI often show a definite visual field preference, for example within the left or right field, or use of peripheral vision.
Difficulty with visual complexity
Pupils with CVI use their vision where the environment is controlled. For example, simple bold targets with reduced visual clutter mounted on a plain background, reduced background noise.
Light gazing and non-purpose gaze
Pupils with CVI can be overly attentive to overhead lights to the detriment of purposeful visual attention. Take care in positioning the pupil and encourage them to look at appropriate targets.
Difficulty with visual distance
Pupils with CVI initially give visual attention to targets nearby. Over time, the pupil may extend the distance of their visual interest.
Difficulty with visual novelty
Pupils with CVI give visual attention to familiar objects. They may not look at novel objects unless they share familiar attributes, for example colour and movement.
Absence of visually guided reach
Pupils with CVI find it difficult to integrate looking and reaching. They may look, and look away before reaching.
For more information visit:
- the CVI Society, a UK charity that raises awareness of Cerebral Visual Impairment providing education and support to families and healthcare professionals
- the Royal National Institute of Blind People (RNIB) page on cerebral visual impairment
- a 19 minute video of an adult with CVI explaining how it impacts on their life