Alzheimer's disease (AD), also called Alzheimer disease or simply Alzheimer's, is a neurodegenerative disease that, in its most common form, occurs in people over 65 years old. Alzheimer's disease is the most common cause of dementia, which afflicts 24 million people worldwide.
Clinical signs of Alzheimer's disease include progressive cognitive deterioration, together with declining ability to perform activities of daily living and neuropsychiatric symptoms or behavioural changes. Plaques which contain mis-folded peptides called amyloid beta (A?) are formed in the brain many years before the clinical signs of Alzheimer's are observed. Together, these plaques and neurofibrillary tangles form the pathological hallmarks of the disease. Until recently (February 2008), these features could only be discovered at autopsy and helped to confirm the clinical diagnosis. In a recent article, researchers have been able to take pictures of amyloid-beta plaques in living mice and compare them to pictures taken in 24 hour intervals, thus able to see how and when these plaques grow. ?At this time, though, medications can help reduce the symptoms of the disease, but they cannot change the course of the underlying pathology.