What Happens To The Brain in Alzheimer's Disease?

The progressive loss of cognitive function in Alzheimer's disease is accompanied by pathologic changes in the brain. One of these is the formation of plaques-sometimes described as tiny "brillo pads"-in the space between nerve cells. The plaques are comprised of a brain protein called beta amyloid. Another protein, which normally channels chemical messages inside nerve cells, deforms and collapses into neurofibrillary tangles that appear like twisted bits of thread inside nerve cells. As the disease progresses, nerve cells in several brain areas shrink and die, including cells that normally produce critical neutransmitters, the chemical messengers that relay brain signals from one nerve cell to another. Acetylcholine is a neurotransmitter that is deficient in people with Alzheimer's. As nerve cells continue to die, the brain itself shrinks and the wrinkles along its surface become smoother.