A New Approach to Understanding Alzheimer's Disease

To many of us, Alzheimer’s disease is a familiar and terrifying malady. Afflicting an estimated 5.3 million people in the U.S. alone, the disorder slowly and relentlessly robs patients of memory, judgment and perception—eventually corroding even their ability to perform everyday tasks. The mechanisms that underlie these symptoms are not yet fully understood. The disease is largely attributed to an abnormal buildup of proteins, which can form amyloid beta plaques and tangles in the brain that trigger inflammation and result in the loss of brain connections called synapses, the effect most strongly associated with cognitive decline.

In a study published this week in Science, a team of researchers led by neurologist Beth Stevens at Boston Children’s Hospital has found evidence that such synapse loss may in fact occur much earlier in Alzheimer’s disease. Rather than being a secondary effect of these protein pathologies, as experts had previously thought, this process may begin well before plaques form....
http://www.scientificamerican.com/article/new-clues-show-out-of-control-synapse-pruning-may-underlie-alzheimer-s/