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Alzheimer’s Brain: Degenerative Changes
Alzheimer’s brain: Changes do occur
 In the Alzheimer's
brain nerve cells stop functioning, lose connections with each other
and ultimately die. The death of neurons in key parts of the
Alzheimer's brain causes those areas to shrink and results in
substantial abnormalities in memory, thinking and behavior.
The Alzheimer's
early symptoms are derived from the destruction of neurons in
particular parts of the Alzheimer's brain controlling memory,
especially the hippocampus (which is why the early signs of
Alzheimer's are related to memory impairment). As nerve cells in the
hippocampus of the Alzheimer's brain break down, short-term memory
fails and the ability to do familiar tasks begin to decline as well.
The disease begins
to attack the cerebral cortex which is responsible for some of the
higher memory functions, such as language, reasoning, perception and
judgment. Sometimes, unwarranted emotional outbursts (known as
catastrophic reactions), and disturbing behaviors such as wandering
and episodes of extreme agitation may appear after the early symptoms
of Alzheimer's appear.
Tangles and plaques in the Alzheimer's brain:
Amyloid plaques
and neurofibrillary tangles are some of the hallmarks of the changes
that take place in the Alzheimer's brain. Although, these changes may
only be confirmed at autopsy, they are found in virtually every
patient with Alzheimer's disease. At the present time, it is not
clear whether these abnormal deposits are the cause or byproduct of
the disease process in the Alzheimer's brain, although researchers
have now come to understand how plaques and tangles are formed. The
increasing knowledge in the area of Alzheimer's disease has helped
with new attempts to block the underlying disease process that may
lead to their buildup. The eventual success of these strategies may
ultimately provide the basis for prevention or treatment in the
future, if these plaques and tangles are determined to be the cause of
Alzheimer's disease.
Amyloid plaques
are known to develop in areas of the Alzheimer's brain related to
memory, and are believed to be a mixture of abnormal proteins and
nerve cell fragments. They may develop from beta-amyloid, a protein
that breaks off from a larger amyloid precursor protein. Beta-amyloid
is formed when the amyloid precursor protein that is embedded in the
cell membrane is broken down for disposal. Enzymes called secretases
split the protein in two and form the beta-amyloid fragment in the
Alzheimer's brain.
Also, See
Alzheimer’s brain-degenerative changes Page 2
Information from The Johns Hopkins
Medical Guide to Health After 50
Additional information and webpage by
Paul
Susic M.A. Licensed Psychologist Ph.D Candidate (Geriatric
Psychologist)
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