Drawing of a Normal Brain

Healthy Brain (left) Brain with Advanced Alzheimer's (right)

Brain with Severe Dementia in Frontal Lobe



Dementia and Alzheimer's Disease

Dementia is a broad term describing several diseases effecting the brain, occur usually but not always, and gradually cause the brain to not function normally. Memory is impaired, as well as language and the ability. There is no cure for dementia. There are a number of forms of dementia. Alzheimer's Disease is the most commonly occurring form of dementia. 50 to 60 % of the cases of dementia are this type of dementia. Approximately 25% of the cases are vascular dementia caused by small strokes in the brains arteries. Lewy body dementia and Fronto temporal dementia (FTD) make up most of the rest, 15%.

A person may have several forms of dementia. Early diagnosis of the type is often difficult and the eventual diagnosis is made at autopsy.

Alzheimer's Disease

Alzheimer's Disease is the type of dementia, which is the most common form. Its progression is slow as it destroys the parts of the brain which perform memory and thinking skills. In most cases it appears when persons are in their mid-60s, but the onset is variable) 50's to 80's) and there is class of Alzheimer's which attacks the brain at a younger age. The functions of the brain that the disease initially attacks are memory(short term memory first), thinking (cognitive) and the behavioral function which eventually (in the later stage of the disease)may become extreme (anger, bizarre activities, agitation and even violence. as the disease progresses to its severe stage. Because of there difficulty in setting the time of onset of the disease. The time from onset (diagnosis)till death has a peak around 10 years, but I have read a number of different texts on the subject , where the death of the patient was 6 years from diagnosis. The 10 year number may have been time from first symptoms to death. The disease development pattern seems to break up into a reasonably consistent pattern; Stage 1, (Mild/Early)), which last 2-4 years (memory and cognitive losses become noticeable followed by Stage2 (Moderate/Middle) in which the Stage 1 losses become worse and the losses in the parts of the brain that control thought, language, and conscious thinking become evident. Processes which involve multiple step processes, such as playing chess or doing your income tax become very difficult. This stage has quite a variability in length, lasting from 2 to 10 years. Finally the last Stage (Severe/Late) which last from 1 to 3+ years is the most heart wrenching, Plaques and tangles ( see references) have spread through the brain. It has shrunk considerably. At this stage, the patient cannot communicate with loved on ones and is completely dependant on them for care. He (she) is bedridden and the body often dies due to heart failure or pneumonia as death occurs.


Since I am a scientist/electrical engineer albeit with a PhD, You should read information on the Alzheimer's Association, or the get the information at their web site www.alz.org , or call them at 1-800-272-3900 More information is available by clicking on the References tab in the right hand column of this web site's main page.

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