Progression of Alzheimer’sAs Alzheimer’s progresses, beta amyloid proteins (plaques) begin to build up in areas of the brain critical for creating, retaining, and extracting memories and for learning new things. Over time, these toxic deposits occupy more and more space in the brain, leaving little room for normal cells to function. It is believed these deposits interfere with the communication between nerve cells.
Several key proteins are deposited in the brain during the course of Alzheimer’s disease, such as beta amyloid protein and tau. The pathology of Alzheimer’s occurs when beta amyloid deposits in plaques and tau deposits in neurofibrillary tangles. This build up of both leads to nerve injury and the symptoms of Alzheimer’s dementia. Most Alzheimer’s scientists believe that the excessive accumulation of beta amyloid proteins actually induces nerve cell tangles to form.
It is important to consider that while abundant brain beta amyloid protein is considered necessary for Alzheimer’s, it is not sufficient to cause the disease. Amyloid must first trigger tangle formation for dementia to ensue.