What is CVI?


Home: Learning - CVI Severely Learning Delayed

This page is a sub-section of Learning at Home, and is about how learning can be optimised for people who have CVI and severe learning challenges.

The foundation of this information relates to how the brain processes information, and how this can be affected by CVI.

(For additional information please follow the links on this page.)

In the main Learning at Home section we highlight three issues, related to learning:

  • 1) Purpose - Is there a purpose that's useful to the person with CVI that will enhance their life, learning and development?
  • 2) Environment - Is the environment, that is the physical room, area, place where the person with CVI is, suitable for them to learn?
  • 3) Substance - This a big category that covers the person who is teaching, the methods used, the materials employed and whether they can be seen and understood, how much time is given, and whether the person with CVI is able to try things for themselves, and much more.

Please read the Learning at Home section first, for a more detailed explanation.

Severely Affected
We use the term 'severely affected' to mean those with CVI who have significant learning challenges, including those who are unable to talk and have very limited communication skills. Many will have significant mobility issues, and will rely upon support for most of their personal care. In our CVI Classifications section, this is CVI Classification 1.

1) Purpose

What are the needs of those severely affected by CVI? This will vary from person to person, but from our many conversations with parents, the following issues regularly come up:

  • Communication - people severely affected by CVI have enormous problems communicating, which is a cause of frustration and stress for everyone involved, especially the person with CVI (see our section Language for non-verbal children with CVI).
  • Sensory challenges - in addition to the visual challenges CVI creates, many who are severely affected also have great sensitivity to sound and noise (see our section on Cerebral Auditory Impairment). They don't like touching things they don't already know (tactile averse) and are very resistant to trying new foods (taste averse). These challenges across the senses create a wall between the person, and their exploration and enjoyment of new experiences.
  • Controlled Movement - this is about having control over your own body and being able to do things, like reach out for something, touch or point, hold something, and bring something to one's face to explore.
  • Head sensitivity - we mention this because so many families have mentioned it to us - a hatred of anything on the face / head, including teeth brushing, face washing, hair washing and hair cutting, making these things stressful and difficult - but they are a necessary part of everyday life.
  • Walking - for those who have independent mobility, walking, whilst liberating, can be fraught with hazards, including tripping over things that are not seen, and things causing frights because they may suddenly loom in front of the person.
  • Recognising People and their facial expressions - facial recognition is likely to be extremely difficult and some may only recognise a small number of very well known people. The language of facial expression may also not be evident.
  • Emotional intelligence - Please read our section on Emotions. Those most severely affected have limited expression of emotions such as sharing appreciation, or showing dislike. This can relate to having limited means of communication, and to how their own emotions have developed.
  • Behaviours - Please read our sections on Behaviours. For so many of those most severely affected, there are many reasons why life can be challenging and frustrating, and so behaviours develop, some of them physical, like pinching or biting. Other behaviours may include not wanting to go out, not wanting to go to new places and not liking new people. These behaviours create another wall between the person with CVI, and their ability to experience and enjoy the world.
  • Vision - there are many things that can be done in the home to help the child learn how to use and control their vision more effectively. We will be writing a dedicated section on this.

This is just a very short list. Think of the person you are supporting, who is severely affected by CVI perhaps putting together their own personal list.

It is important to remember that behind all the challenges and behaviours is a person, who likes adventure, to explore and have fun - just like everyone else!

Those severely affected by CVI are also adventurers, explorers and love to have fun!Those severely affected by CVI are also adventurers, explorers and love to have fun!

2) Environment

In the previous CVI Scotland's Learning Spectrum section we introduced a simple coloured system:

Thinking about the environment for the person severely affected by CVI we need to balance two different areas:

  • a) Is it easy or difficult?
  • b) Is it known or unknown?

a) Easy / Difficult Environments

Considering what the brain is needing to do, the easiest environments for those most severely affected by CVI are environments with minimal clutter and few people (see our section on clutter).

A single coloured tent like the one below creates an optimal environment, particularly if it is somewhere quiet.

The more cluttered a place becomes the more challenging it is, and for some, the more threatening. Clutter includes noise and movement, as well as visual clutter (see our sections on Attention & Its Calibration).

Difficult environments can become less challenging if they become known.

b) Known / Unknown Environments

Let us take the busy supermarket in the image above, the photo was taken by a mother who has her son, who is severely affected by CVI, with her at the time. She explains:

For a long time I couldn't take my son anywhere, and I decided to start trying to get him out a little bit at a time. Supermarkets are very difficult and stressful, but I started going when it was really quiet and only for a few minutes. My son loves reaching out and touching things as he goes past them, but always from the safety of a chair, and I am always there. Bit by bit we built up the amount of time he can tolerate. If it is busy we still have to be quick, but it is because there is so much movement and noise, and I think he knows the visual layout of the store well now. When it is quiet, I can get a family shop done, and he doesn't just tolerate it, he enjoys it. His school are doing something similar, and he regularly goes to local cafes for a treat.

For this boy, the supermarket has gone from difficult and unknown (red zone) to known. It is always going to be a challenging environment, but now it is known, it is less challenging.

The store has become known to the boy, which means through repeated consistent experiences this environment has become stored in his memory. So he knows where he is. This has been built up over a long time. For those severely affected by CVI, learning a new environment can take many repeated visits (some of the reasons are explained in our Limited Area of Visual Attention section).

If an environment is difficult (red zone), and is unlikely to be repeated regularly, like a party for example, try to think of it from the perspective of the person severely affected by CVI:

  • who may not know where they are
  • why they are there
  • what is going to happen

Which may make them

  • anxious
  • frightened
  • confused

And this definitely is not an environment for learning.

If the environment is in the red zone, you should think about what you can do to make it less challenging, like de-clutter or slowly let the person get to know the environment when it is quiet.

As a general rule, the red zone is anything that is either unknown or difficult or both, with the exception of working in tents. We have many accounts of children entering the world of a single coloured tent for the first time, so it is unknown, and immediately responding positively to the environment by engaging, relaxing, reaching, smiling, and vocalising. We also have an account where a child treated the new experience of a tent with initial suspicion, but very quickly learnt to love it.

3. Substance

We suggested the following examples of Learning Substance in the previous section Learning at Home:

  • The people working with the person with CVI, in whatever capacity, may be a sibling playing or a parent reading, or a home teacher or therapist.
  • The form of communication or contact - is it understandable for the person with CVI?
  • The materials used, like toys or games or things to touch - are they matched to the person's vision and so, accessible? Do they make sense? Do they have meaning?
  • The speed - might things be going too fast? Can you slow things down? Can you allow more time?
  • Does the person get to do things for themselves? Learning is considerably more difficult when people do things for you.
  • Content - is it already known, or not yet known, but learnable. Or does it need to wait until more is understood? (see Gordon Dutton's blog 13)

This may seem like a lot to consider, but once again we need to break it down into

  • a) Easy / Difficult
  • b) Known / Unknown


  • Think, from the perspective of the person with CVI - who do they know best? And importantly, like most. Maybe a parent, sibling, favourite therapist who visits the house or family friend.
  • Who don't they like? How do they show this? Can you figure out why?
  • The people who are most known and liked by the person with CVI, and also have taken the time to understand the unique nature of their visual world, and know their history and development, are the best!
  • Others, who may be skilled but are not known to the individual so well, can be helpful but less effective because they are not well known.
  • People who are not known to the person with CVI, and do not understand their visual world and challenges may be difficult - think of the visiting relative who feels they are being friendly - but to the person with CVI they may be a scary invasive stranger!


We know that many severely affected by CVI have great difficulties communicating. Those closest are likely to understand from sounds, facial expressions and body posture and movements if the person is happy or agitated, but many others will not. If these signs are not correctly interpreted it can be extremely stressful for the person with CVI.


This can be anything from toys to food to bubbles in the bath. One question - is it perceivable? We have explained in Access, that for the brain to learn there needs to be a repeated cycle of:

  • Experience
  • Memory
  • Recognition

And the Experience bit of that cycle needs to be perceivable, and matched with meaning whilst the person is motivated.

In the introductory section we described colander vision, and this is just one of the many reasons why materials are not always perceivable to be learnable, because only a small part may be visible - so the person cannot learn! Other examples of materials not being perceivable include:

  • Things being too small - do you have a visual acuity measurement for the person with CVI? If so convert it to a line width (using our table on this page). To be remembered visually things need to be visible - so they need to be big enough, but...
  • Not too big - as many severely affected by CVI may have reduced visual attention, and making things bigger means they are only able to see a part, which will make learning what it is, much more difficult (see our The Visual Acuity / Simultanagnosia Problem section).
  • Insufficient contrast
  • Toys and other things that do several things at once, (e.g. different tactile surfaces, movement, flashing lights, the sound they make), can be overwhelming. Such toys can be learnt, and we know are loved by many severely affected by CVI, but there can be a lot of different processing demands being made at the same time, making learning the toy more difficult.

These are just a few examples, more can be found in our What Is CVI? sections under the different headings. We explain the process of making things known, bit by bit, in our Zoom In Zip Up Zoom Out sections, with examples around a children's playground, food and an orchestra.


We explained in our movement section that if things move too fast, they may not be visible to the person with CVI. For the purpose of learning, if something is moving too fast to be visible, then it is not possible to learn it visually - we cannot learn from what we cannot perceive.

Doing things for themselves

For all of us, we learn to do things much more effectively if we are able to do it for ourselves, whether it is making a cake, driving a car, reaching to press a button or holding the spoon being used to feed us. This is down to how the brain learns, and it will learn more quickly and more effectively when the person is doing something for themselves, rather than someone else doing it for them.

Known or Unknown

As with the previous section:

  • Difficult = red zone
  • Unknown = red zone

Converting something unknown into something known, can gradually change a red zone into an orange zone, eventually proceeding to green.

The ideal is the green zone, where:

  • The accompanying person is the most known and loved
  • Communication takes place in a way the person with CVI understands (ideally by means of language, see Language for non-verbal children with CVI)
  • Only perceivable and meaningful materials are used, while the person is motivated
  • Things to learn are moving at a speed that can be perceived clearly
  • The person is enabled to try things for themselves
  • With an understanding of what is known and not known, the person teaching slowly facilitates learning of the 'yet to be known'.

And we are back to where we started at the beginning of the previous section:

"we think home is the place where there are the greatest learning opportunities for the person with CVI. Here are our reasons:

The time the person spends at home (85% roughly, see Home section)

The unique expert knowledge the people at home have of the person with CVI, not just how they are affected by CVI, but also their experiences across their whole life to date.

The time, love, patience and motivation those at home have for the person with CVI, which goes above and beyond anyone else's."

Here is the Learning spectrum as a table (see CVI Scotland's Learning Spectrum).

  • For optimal learning, you need to aim for the green zone.
  • In the orange zone, seek out where improvements can be made.
  • Avoid the red zone.

So let us take our adventurers and explorers out to have some fun and learn at home!

The Five Areas

In every sub-section of Home, we consider learning experiences across the five broad areas listed below. These cover how many with CVI spend their time, but do not cover all the time for everyone. Hopefully they will help you to relate what we are explaining, to the individual with CVI.

1. Time at home and in the garden.

Home is known, so even if the house is cluttered, it is already an orange / green zone. Look to see if you can make the environment easier by decluttering and, if you have space invest in a tent (which pops up and down for easy storage).

Think about the explorer, and across the senses, keep exploration clear, slow and purposeful. Explore different foods with different smells and textures, in the garden feel different grasses, flowers, plants and trees, smell them, listen to the birds, and use clear the singular word to name what is being experienced just after the experience (see Language for non-verbal children with CVI).

Use the garden to learn -  feel the grass, smell the flowers, listen to the birds.  These are purposeful meaningful experiences that will always be relevant.Use the garden to learn - feel the grass, smell the flowers, listen to the birds. These are purposeful meaningful experiences that will always be relevant.

Many children who are severely affected by CVI love television or tablets, and this can be used to help further learning, for example developing language, by maybe giving a programme a simple name. (See Language for non-verbal children with CVI).

If a favourite programme can be watched on a computer (many are also available on You Tube), try playing with the speeds a little (click here for instructions). This is a really good way to get a sense of the person's preferred speed, and once you understand it, you can let others know. The world is simply too fast for many severely affected by CVI; you can make sure everyone knows to slow down, and by how much.

Don't forget fun, so many children with CVI love trampolines and swings, and being in the garden, playing with the family, helps build and strengthen social relationships.

2. Night Time / Sleeping / Not Sleeping

Reading! Please see our section on Reading to your child for fun. Even Connor, who can't see the pictures or understand the words loves his stories - they take him on a wonderful journey somewhere - remember the explorers!

We know many severely affected by CVI have difficulties with sleep. Ensuring the environment is optimal, and the process at bedtime, including the known person, loved story, familiar things, keeping as much in the green zone as possible, will help, because the process is made much easier to learn, which means it will make more sense.

To help with the environment in the bedroom, up-lighters prevent light gazing, while shaded lamps that can be touched to control the level of light can empower some children.

3. Trips (e.g. shopping, play parks, sports, parties, outings)

We have already mentioned that parties, and any similar environment that is difficult (red zone), needs to be gradually learnt about, often involving multiple visits, by the person who is severely affected by CVI.

Sometimes even with difficult environments this can be beneficial, for example regular playgroups or social groups.

We may have happy memories as a child of going to parties, special treats, days out at funfairs and carnivals or going to see shows. Try to think of these things from the perspective of the person severely affected by CVI, as they will not experience it in the same way you did.

We shouldn't assume that just because we think something or somewhere will be nice and fun, that the person severely affected by CVI will experience it in the same way.We shouldn't assume that just because we think something or somewhere will be nice and fun, that the person severely affected by CVI will experience it in the same way.

Please always try to remember the perspective of the person with CVI, things may not have the same happy associations.

For children who are more aware, or if an event is unavoidable, please see our suggestions in the following section (CVI Mild / Moderate Learning Delayed) where we share many tips helping a child with CVI through birthday parties and other events that may be challenging.

4. Car journeys

For many, the environment within the car is likely to be well known, so it may be an orange or green zone (if the car is uncluttered). This means there are great learning opportunities within the car, particularly with well known people, including developing language and reading.

For some, car journeys can be frightening. Parents have told us of some of the approaches they have discovered help improve the environment:

  • Listening to favourite music
  • Watching a favourite video on a tablet
  • Wearing noise abating or noise cancelling headphones
  • Dark wrap around child ski glasses, can cut down the discomfort of the visual experience of the journey
  • A screen over the child's window can eliminate fear, which could be due to looming.

5. Socialising and visits to friends and relatives and holidays.

Some of these events can be brief and unknown, and thus challenging (red zone). They can provide opportunities to learn about new people and places, but this needs to be at the pace that the person with CVI can comfortably manage, especially when purposeful to them (the person with CVI).

Further thoughts

As far as possible try to aim for the green zone, but be mindful that once something is very familiar and learnt, it can become boring, and the explorers will need new adventures to keep their brains busy and happy. So learning develops...


Your generous donations will be put to immediate use in supporting our charity...

Donate Here

About Us

At CVI Scotland we are devoted to helping people understand cerebral visual impairments, and together working towards developing the understanding of this complex condition.