Dementia is not a natural part of the ageing process. It’s caused by illnesses that affect the brain.
Dementia is an umbrella term for over 100 different types of diseases and symptoms, and it's possible to have more than one type. What all these diseases have in common is that they damage brain cells, so that the brain cannot work as well as it should.
Dementia can affect every area of human thinking, feeling and behaviour, but each person with dementia is different - how the illness affects someone depends on which area of their brain is damaged.
There are many conditions which cause dementia - these are some of the most common. It is also possible to have more than one type of dementia at the same time.
- Alzheimer’s disease gradually destroys brain cells and their connections. This affects how the person copes with everyday tasks.
- Vascular dementia is caused by problems with the blood supply to brain cells. It can involve tiny strokes which damage small areas of the brain.
- Dementia with Lewy bodies isn’t as easy to identify as some other types of dementia, so it can be hard to diagnose. It can include hallucinations and symptoms that are similar to Parkinson’s disease.
- In frontotemporal dementias, the parts of the brain responsible for decision-making, control of behaviour and emotion and language are affected.
Find out more about other types of dementia.
In Scotland, over 90,000 people have dementia. It is most common in older people but can affect people in their 40s and 50s or even younger.
We do not yet know exactly what causes dementia. Medical researchers all over the world are working to find causes and develop treatments. Learn about dementia research.