Dementia is an umbrella term. It describes the symptoms that occur when the brain is affected by certain diseases or conditions. There are many different types of dementia although some are far more common than others. They are often named according to the condition that has caused the dementia.
This is the most common cause of dementia. During the course of the disease, the chemistry and structure of the brain changes, leading to the death of brain cells.
If the oxygen supply to the brain fails, brain cells may die. The symptoms of vascular dementia can occur either suddenly, following a stroke, or over time, through a series of small strokes.
Dementia with Lewy bodies
This form of dementia gets its name from tiny spherical structures that develop inside nerve cells. Their presence in the brain leads to the degeneration of brain tissue.
In fronto-temporal dementia, damage is usually focused in the front part of the brain. Personality and behavior are initially more affected than memory.
Rarer causes of dementia
There are many other rarer causes of dementia, including progressive supranuclear palsy and Binswanger’s disease. People with multiple sclerosis, motor neuron disease, Parkinson’s disease and Huntington’s disease can also be at an increased risk of developing dementia.
Creutzfeldt- Jakob disease
Prions are infectious agents that attack the central nervous system and then invade the brain, causing dementia. The best-known prion disease is Creutzfeldt-Jakob disease, or CJD.
Korsakoff’s syndrome is a brain disorder that is usually associated with heavy drinking over a long period. Although it is not strictly speaking a dementia, people with the condition experience loss of short term memory.
HIV related-cognitive impairment
People with HIV and AIDS sometimes develop cognitive impairment, particularly in the later stages of their illness.
Mild cognitive impairment
Mild cognitive impairment (MCI) is a relatively recent term, used to describe people who have some problems with their memory but do not actually have dementia.