What is dementia?

These pages explain what dementia is, including the causes and symptoms, and how it is diagnosed and treated. They also look at the different types of dementia.

Along with all our usual information on dementia, we have more advice to support you during coronavirus.

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Coronavirus has been particularly tough for those affected by dementia. The latest restrictions mean people will be experiencing increased loneliness and an acute sense of fear.

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What is dementia?

The word ‘dementia’ describes a set of symptoms that may include memory loss and difficulties with thinking, problem-solving or language.

These changes are often small to start with, but for someone with dementia they have become severe enough to affect daily life.

A person with dementia may also experience changes in their mood or behaviour.

Dementia is caused when the brain is damaged by diseases, such as Alzheimer’s disease or a series of strokes. Alzheimer’s disease is the most common cause of dementia, but not the only one.

The specific symptoms that someone with dementia experiences will depend on the parts of the brain that are damaged and the disease that is causing the dementia.

Watch our video to learn more about dementia

Accessible versions of 'What is dementia?'

Access this information as an audio file or as a British Sign Language video. 

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More practical and emotional support near you

There are dementia services and support groups in your area. Find out what's available where you are.

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