Posterior cortical atrophy (PCA) is a rare form of dementia that usually begins by affecting a person’s vision. It is also known as Benson’s syndrome.

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What is posterior cortical atrophy (PCA)?

Posterior cortical atrophy, also known as PCA, is caused by damage to the brain cells at the back of the brain. This is the part of our brain that processes the information from our eyes and allows us to make sense of what we are seeing and where things are.

Alzheimer’s disease is most often the cause of the brain cell damage in PCA, but it is sometimes caused by other types of dementia, such as dementia with Lewy bodies. In very rare cases, conditions called corticobasal syndrome or Creutzfeldt-Jakob disease can cause PCA.

You can read about other types of dementia like Alzheimer’s disease, dementia with Lewy bodies, or rare types like corticobasal syndrome here.


PCA is sometimes called ‘visual variant’ or ‘visual-spatial’ Alzheimer’s disease. However, the early symptoms of PCA and typical Alzheimer’s can be very different.

Alzheimer’s disease usually affects a person’s memory first, but in PCA the first symptoms are often problems with vision and how we understand what we are seeing and where things are.

People often develop PCA between the ages of 50 and 65, but it can affect older people too. PCA is a rare form of dementia, and at the moment we can’t be sure how many people around the world are affected by it. Of people diagnosed with Alzheimer’s disease at specialist dementia clinics, around 8 to 13% may have PCA symptoms.

What is posterior cortical atrophy?

Find out more about the symptoms and causes of posterior cortical atrophy, and the treatments currently available.


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This information was written in April 2021 and is due for review in April 2023. Please contact us if you would like a version with references.

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