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Posterior Cortical Atrophy

Audio version of this page. Read by Professor Gordon DuttonVideo Link: https://vimeo.com/615297424

What does Posterior Cortical Atrophy mean?

Posterior Cortical Atrophy is an anatomical name, meaning it is a medical term related to a part of the body.

Posterior means at the back of.

Cortical means of the cortex.

You may have heard the term 'grey matter' in relation to the brain. The grey matter is the outer layer of the large part of the brain that looks a bit like two walnut halves, called the cerebrum.

Diagram of the left side of the brain showing the cerebrum, cerebellum and brainstem.Diagram of the left side of the brain showing the cerebrum, cerebellum and brainstem.

The cerebrum is made up of an outer layer called grey matter, because it is darker than the layer underneath (called white matter).

The outer grey matter layer is called the cortex. So the word cortical in posterior cortical atrophy is this grey matter.

The outer layer of the cerebrum, made up of grey-matter is called the cortex.  Cortical means of the cortex.The outer layer of the cerebrum, made up of grey-matter is called the cortex. Cortical means of the cortex.

So that is what cortical means, but where is 'posterior' in relation to the cortex?

The area at the back of the cortex in relation to this condition is in an area of the brain called the parietal lobes.

To locate your parietal lobes, put your palms over your ears, as you might if something is too loud. Adjust the position of your hand so the thumbs are pointing towards each other at the back of your head and the fingers slightly higher. Your fingers are over the approximate area where your parietal lobes are. You have two parietal lobes, one on the left and one on the right side of the cerebrum.

Simple demonstration of where your occipital, parietal and temporal lobes are.Video presented by Professor Gordon Dutton.Video Link: https://vimeo.com/600263755

Looking at the back of the head, the area at the bottom of the parietal lobes, called the posterior parietal lobes, is the posterior in posterior cortical atrophy. Where your hands were in our exercise, approximately under your index fingers.


The word atrophy originates from the Greek to mean without food so poorly nourished.

In modern medical terms, it means to decline or deteriorate.

Posterior cortical atrophy means that a part of the brain, in the area of grey matter at the back of the parietal lobes, has begun to not work so well. It is a progressive condition and the rate of progression varies from one person to another.

Posterior cortical atrophy is a type of dementia. It can present very similarly to Alzheimer's Disease which is a much more common but different type of dementia.

In many with posterior cortical atrophy, it is vision that is affected at the beginning. This is because the posterior parietal lobes are one of the main vision processing centres in the brain.

The purpose of this page is to explain how vision is affected and to offer practical suggestions we think may be helpful. We know the condition is serious and challenging, but we also know there is a person - you may be that person, or you may be helping them. We want to help by explaining how and why vision is affected, and by suggesting approaches that people with such visual difficulties and their close relatives and friends have found to be effective.

Which bits are vision?

Our posterior parietal lobes receive the information from the eyes and ears about the surrounding visual scene and sounds. They work out where everything is and where sounds are coming from. They also carry the messages from the eyes about the lower part of the visual scene.

This means that when they are not working so well, finding things can be difficult. It can also be difficult to know where sounds are coming from and to concentrate on what is being said. This can also lead to tripping because the ground ahead may not be seen so well.

This 'movie' picture in the posterior parietal lobes is also responsible for guiding our body movements, so reaching out, picking things up and moving through crowded places can become less accurate than they were.

With posterior cortical atrophy, these skills are often the first to be impaired which can progress to give rise to many different issues affecting a person's ability to recognise, remember and understand. Together these might sometimes be considered 'cognition' or cognitive abilities, which is about how you understand and interact with your surroundings and the people you are with.

The problem with issues with cognition, is that there can be multiple causes. For the person we want to help, we are going to explain where vision might be a specific cause, and provide some simple suggestions. It is not always going to be possible to have everything formally assessed, we know that, but our suggestions are designed to be simple. If they help, great, if they don't, then maybe it is not the area of vision causing the difficulties, but they certainly will neither harm nor hinder.

This page has been deliberately kept very simple, listing in sections the various difficulties and suggestions of ways to deal with them. There are further reading links at the end if you want to learn more.

The areas we are going to cover are:

  • Finding Things - This includes finding your way around, not just places out and about but in the home and familiar places, and many ways this can be made easier.
  • Independence - All the things so many take for granted, like getting dressed, personal care, preparing food - simple adaptations to cater for the visual difficulties might make a surprising difference.
  • People - recognising people and understanding their emotions are a key part of social relationships, and there are many simple things a person can do to make this easier where visual processing might be causing difficulties.
  • Clumsiness - we hate the word 'clumsy' because it is so negative and implies someone is at fault, which is almost never the case, and definitely not with posterior cortical atrophy, but we know most will know what it means, so we are using it for simplicity alone. There are also a number of simple ways to overcome this difficulty too.
  • Reading & Writing - There are many different reasons reading and writing can become difficult, and may become increasingly difficult over time, but there is a great deal you can try which may help.
  • Relaxing - There are many ways to 'feed' the visual brain, to help with relaxation and feeling calm.

Finding Things

Ways to make finding things easier.Ways to make finding things easier.

Finding Things
Difficulty: I can't find things like a jar in the cupboard, or the shirt in the wardrobe, or my toothbrush on the bathroom shelf.

Try: Organise cupboards, shelves and drawers in an order that can be remembered, and remove anything that is not necessary, also remove / replace backgrounds that may have a lot of patterns like wallpaper or curtains. Once the order has been established, keep things in the same place, and get everyone in the household to do so too, while explaining why. Don't just use your vision to search, practise reaching out and feeling for the items too.

Why? Seeing more than one thing at a time may be difficult, but it is not practical just to have one tin in a cupboard. Reducing unnecessary patterns and the number of objects, to reduce clutter, means there is less for the brain to visually process, which can make looking and finding things much easier. Keeping things in the same place means that the memory of where they are kept can be used to help find them. Learning how things feel will support your vision, like a double check.

Finding your way around
Difficulty: I can't always find my way around. Sometimes I feel lost and disorientated, including in well-known places like my home and neighbourhood.

Try: Making up simple rhymes or poems to remember a route in stages - this might sound silly, but we have heard of great successes, so from home to the local shops and back maybe 'outside home is a red post box, walk towards the door with a fox, look for the window with curtains blue, the shop's next door, buy something new". And reverse it for the way home. Try similar rhymes to find things in the home. They don't have to be great rhymes, just simple and easy to remember.

Why? Routes are very complex large visual memories, and remembering routes is a complex visual process. Long routes from one town or city to the next, or short routes, to a different room to find something, can all be difficult due to visual processing issues. With a rhyme, you are supplementing that difficult process with a little helping hand, using a different part of your brain.


There are many different ways to do many different everyday tasks.There are many different ways to do many different everyday tasks.

Everyday Tasks
Difficulty: I am struggling with basic things like getting dressed without help, brushing my teeth and washing, and preparing food.

Try: Organise things so they are easy to find (see Finding Things, above), use tactile cues and learn to feel the experience of what is being attempted, for example spreading butter on some bread, rather than just looking at it, practice learning the feel of the bread, where the edges are, what the knife feels like when spreading and how different it feels when there is no spread on it. Feel the toothbrush as you put toothpaste onto it, to learn how much you have to squeeze to get approximately the right amount. It may also be worth trying some of the tactile support objects and devices provided by some vision organisations.

Why? These tasks are not just visual tasks, they are multi tasks. As you have been doing these tasks most of your life, you will have formed complex memories (called haptic memories). If vision is causing the difficulties, or contributing to them, then this is a time to start strengthening those existing haptic memories, to help with all the day to day tasks. The sooner you start practicing the better!


Recognising People
Difficulty: I often can't find nor recognise people, including people I know really well like my own family members.

Try: If meeting someone, ask them to wear something high up that will stand out and be easy to spot from afar, like a red hat or scarf. Listen out for their voice, and the pattern of sounds while they are walking. Explain your difficulty and ask people to slowly approach you and introduce themselves both by their name and how they know you, for example Hi, it's Trudy from the Library.

Why? Faces are extremely complex in visual brain processing terms. There are many reasons why recognising faces is difficult, and whilst there are some visual search exercises that can help, these can take time and a lot of discipline to master, and may not be the most effective approaches. We know being open about the difficulty is one of the easiest and most effective ways of dealing with it, so people know it is not personal if they are ignored, they just have not been recognised. It might seem odd to begin with, to have someone you know very well introduce themselves as though they were addressing a stranger, especially if they are very well known. If a meeting is pre-arranged, then agreeing where to meet, and where the person will be standing, with an easy to recognise item of clothing, means they can be recognised not by their face but where they are or what they are wearing.

Think about a play or programme on the radio, where the people are not seen, only heard, so how they are feeling, if important, needs to be expressed so it can be heard.Think about a play or programme on the radio, where the people are not seen, only heard, so how they are feeling, if important, needs to be expressed so it can be heard.

Following Emotions in Others
Difficulty: I feel like I am missing understanding how people are feeling, and I think it may look like I don't care or am insensitive, when nothing could be further from the truth.

Try: Encouraging people to talk to you like they are on a telephone, or in the way people communicate through the radio, where there are no pictures. When communicating how they are feeling, for example excited or worried, ask the person to use the words to express themselves, not facial expressions or tones of voice, and allow you a little time to process and understand, and if needed, ask questions.

Why? Most emotional messages are not spoken but can be very difficult to pick up, where a facial expression may be fleeting, or tone of voice confusing. Often, the tone of voice needs to be paired with the fleeting expression to make sense, making it even more difficult to pick up.

Below is a clip from a BBC Radio 4 series called The Archers. Listen to a little and think about how they use their voices to communicate to the listeners without being seen, and encourage others to do the same.

Video Link: https://www.youtu.be/CD62e3CGIR8

Going out and socialising can be stressful, but there are many things you can do to make it more enjoyable.Going out and socialising can be stressful, but there are many things you can do to make it more enjoyable.

Difficulty: I used to love going out and meeting people, but have found it increasingly difficult.

Try: Think ahead and plan as much as you can, for example in a restaurant where you will sit, can you have a table facing a plain wall or in a quieter area? Can you see the menu to select what you want in advance? If trying to rebuild confidence going out, start small, with trusted people in quiet places, and build up your confidence as is comfortable. Think of an 'exit plan' if you feel overwhelmed, for example think of someone you can phone to assist you. Just having an exit plan can help you feel much more comfortable and calm, knowing you are safe even if something is difficult. Think of alternatives that work for you, which may mean people coming to your home to visit you, or going out and about at quieter times.

Why? Out and about socialising is the great unknown, and whilst it can bring great joy, it can also bring unexpected stress or even frights.


To reduce the risk of breaking things, you may need to learn to really slow down and think about what you are doing when reaching for things.To reduce the risk of breaking things, you may need to learn to really slow down and think about what you are doing when reaching for things.

Feeling Clumsy
Difficulty: I am constantly dropping, breaking, knocking into and missing things.

Try: Using a part of your body to help, so adding touch guidance, for example when reaching for the cup, slowly move your hand along the table not through the air, and have your finger outstretched, until your reach it. Or if playing the piano, rest your knees under the keyboard. This helps you to locate the position of the piano. This is called tactile guidance.

Why? Your body is full of systems telling you where things are and just because some of the visual systems may not be reliable, meaning you break things on knock things over, it does not mean the other systems are not still working. You can create an alternative or supplementary tactile system of guidance for any part of your body with anything you are doing. This tells your brain where things are in a different way, and this can be very effective and aid accuracy of body movements and reaching.

If worried about stumbling, tripping and bumping into things, spring loaded hiking poles can provide a tactile source of information to your brain about where you are in relation to everything around you, to keep you safe.If worried about stumbling, tripping and bumping into things, spring loaded hiking poles can provide a tactile source of information to your brain about where you are in relation to everything around you, to keep you safe.

Trips & Stumbles
Difficulty: I have stumbled and tripped a few times, and bumped into things and people, and am finding I am nervous going down stairs.

Try: Slow down, and as you approach things like doorways to navigate, learn to put a hand out to the side to feel where it is as you walk through. When out and about try using a spring loaded hiking pole, and when on stairs or escalators, especially going down, be very careful and always use the rail.

Why? The rail on the stairs, hiking pole and your arm touching the side of doorways all give your brain a secondary source of information about where you are in relation to what is around you. Where the primary source you have previously relied upon to do this, your vision, is less reliable, this can help. With stairs and anything going downwards, it is possible the lower part of your vision is not as reliable as it once was, and so extra care needs to be taken.

Reading & Writing

Too many words in a small area, called crowding, is a common reason for reading difficulties, and using a reading programme, like our free e-reader LOOK, where fewer words are shown at a time, can help.Too many words in a small area, called crowding, is a common reason for reading difficulties, and using a reading programme, like our free e-reader LOOK, where fewer words are shown at a time, can help.

Difficulty: Reading is difficult, I'm not sure why, it just is!

Try: Experiment with a number of different things, including larger text, same size text but greater spacing between the letters in the words or a different font and fewer words. You can do all this using our free e-reader LOOK. Also try reading when it is quiet and somewhere calm and ideally clear and uncluttered. There are different audio translator systems, a local service for the visually impaired should be able to help you pick one if needed.

Use a paper-weight / dome magnifier that you move over the paper on a table.

Why? There are multiple reasons why reading may be difficult, which is why we suggest trying a number of approaches, but crowding may well be a cause of difficulties, this is where the brain might still be able to comfortably reading just one or two words at a time, but struggles with a full page of words. Our free e-reader was designed with this particular difficulty in mind.

Short demonstration of our free reading tool LOOK. Links to use at the end of this page.Video Link: https://vimeo.com/605611126

Has writing become unreadable?  Has writing become unreadable?

Difficulty: My handwriting is now illegible, I feel like I know how to write still, but it is just a mess on the page.

Try: Using paper with wide thick lines, and when putting your pen / pencil on the paper, use a finger from the other hand to mark the place you want the pen to go. You can also use a 'signature guide' if needed, available on-line of through vision organisations.

Why? This difficulty likely has the same cause as clumsiness (above) and the finger is serving as a tactile guide, to help accurately place the pen or pencil where you want it to go to write.


Your brain is working very hard and needs breaks.  Somewhere quiet and calm where you feel safe is ideal,Your brain is working very hard and needs breaks. Somewhere quiet and calm where you feel safe is ideal,

Difficulty: I am often stressed, partly because I am easily startled, but also I am regularly feeling overwhelmed and find it difficult to relax and wind-down or switch-off.

Try: Going outside somewhere open, quiet and calm, so few people, like a quiet beach or the countryside. If indoors, organise an area so you have a completely clear space, maybe a comfortable chair facing a wall or curtains without patterns. Sit and rest, and try to do this often.

Why?: Your brain is working very hard, and it needs breaks. Sometimes shutting your eyes when stressed can just feel like intensifying the worries. Going somewhere open but clear sort of nourishes your visual brain, and we know from many accounts that being in these environments can create a feeling of calm, which persists for some time. These breaks are essential. Take as many as you need or want. This is you looking after your brain, to help your brain look after you.

Further reading

We have kept the information on this page very short, but have many resources if you want to learn more. We have organised further reading suggestion under the same section headings we have used on this page.

All the further reading is written in the same style of using simple language. Some page names below use technical terms, but don't let that put you off, everything is explained.

We have also written a series of free short lessons to help understanding, for anyone who wants to learn, with no prior understanding needed. CVI Scotland's Lessons.

Blogs about Posterior Cortical Atrophy
Gordon Dutton's Blog 22 - Preventing Fear and Anxiety
Gordon Dutton's Blog 35 Visual Role of the Posterior Parietal Lobes

More information
Rare Dementia Support, part of the Dementia Research Centre of University College London (UCL) has more information and resources on posterior cortical atrophy. Click here to view.


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