Our Aging Brains

       People 80 or over are now only slightly more than 1 per cent of the total human population, but this proportion is projected to increase almost fourfold over the next 50 years, to reach 4.1 per cent, or almost 379 million worldwide, in 2050. In 2050, 19 countries, mostly in Europe, are projected to have at least 10 per cent of their population aged 80 years or over. Aging is no longer a personal or family issue: it is a globalizing phenomenon that is going to influence the lives of millions to come.

       What are the first few things that come to mind when you think about aging? Or of the elderly? Dementia? Blurred speech? Or the slowness in processing information and learning? All of those issues are the result of the atrophy of the aging brain, the gradual dying of grey matter and the shrinking of brain volume. By the time we are eighty, our currently growing brains would have lost at least 15% of their grey matter, shrunken to size of those of two or three-year-olds, and lost 40 percent of its dopamine function. Even more disheartening is the inevitable loss of the neural network of connections in our brain, the “dendritic trees,” that allow a single neuron to be connected to a thousand others: by the time we are old, the "tree" would have shrunken to 3/4 of its original magnitude. What those changes to the brain cause is the weakening of the aging population's sensory detection, motor (due to the failing dopamine system), memory retention, storage, and retrieval abilities.

       The aging baby boomers' fear of those horrifying effects of brain atrophy and the global aging of human population prove to be great news for publishers, vitamin companies, and computer game designers. But despite the recent explosion of technology and dietary supplements that companies claim to alleviate the effects of aging, according to Elizabeth Zelinski, a gerontologist at the University of Southern California, “There’s no evidence that anything works.” Even more discouraging is what neuroscientist Eric Kandel, a Nobel Prize winner in medicine, have to say about aging. When asked how long it will be before people achieve some reasonable understanding of how memory actually works, he replied, “a hundred years.” A hundred years might not seem like a long time in the history of medicine, but by then, most of us sitting in the classroom together would have been long dead.

       But on the brighter side, a study conducted by Neuropsychologist Yaakov Stern of the Columbia University College of Physicians and Surgeons shows "that more 25 percent of people who function perfectly normally while alive in old age have brains that show serious signs of Alzheimer’s in autopsy," and "people with more education have lower rates of dementia." The study demonstrates that even as the "hardware" of our brain break down, there is definitely the possibility to maintain the brain's function by improving its "software" through certain ways. But in the meantime, all there is to our advantage in combating the effects of aging is "some combination of luck, good genes, and a healthy lifestyle." 

possible research questions:
1. What is the mechanism that is allowing people with obvious signs of Alzheimer's to function normally in everyday life?
2. What defines the "normal" functioning relative to age?
3. What encompass the healthy lifestyle? Are there any evidence that shows certain practices as being able to alleviate the negative effects of aging?

sources:

http://discovermagazine.com/2012/oct/16-brutal-truths-about-the-aging-brain

http://www.un.org/esa/population/publications/worldageing19502050/pdf/90chapteriv.pdf