Dementia is a syndrome, which means that there is a group of
related symptoms. With dementia, the syndrome is associated with a
decline in the brain and the abilities of the brain including
understanding, memory, language, thinking speed, mental agility and
judgement.
The person with dementia may also have difficulties
controlling their emotions and become apathetic. They may act in
inappropriate ways. The person’s personality may also change and they
may start to hallucinate or hold false beliefs. Dementia can also affect
the person’s ability to maintain their independence as they lose their
mental abilities to remember, organise and plan. Dementia is caused by
damage to the structure of the brain. How the damage occurs will affect
what type of dementia develops.
There are many types of dementia, including –
- Alzheimer’s disease – the brain progressively shrinks – atrophy, which damages the structure of the brain and how it works.
- Vascular
Dementia – the blood supply to the brain is interrupted, so brain cells
die, which leads to brain damage. The blood supply can be interrupted
when the blood vessels to the brain narrow and harder, this can be due
to fatty deposits on the cell wall (atherosclerosis). There is increased
risk of atherosclerosis due to smoking, obesity, alcohol consumption,
diabetes, lack of exercise, a high fat diet. The blood supply to the
brain can also be affected if a person has a stroke.
- Frontotemporal
Dementia – the temporal lobe and frontal lobe of the brain becomes
damaged and shrinks. This is thought to be due to a genetic mutation
inherited from parents.
- Dementia with Lewy Bodies – it is
not known what causes this damage. Lewy bodies are small lumps of
protein that develop in the brain. It is not yet known what causes them,
or how they damage the brain or cause dementia.
- Other rarer forms of dementia include corticobasal degeneration and progressive supranuclear palsy.
This is an extract from our ebook, Brain and Behaviour (publication date - early April. 2015)