Monday, April 30, 2012

Memory declines as age goes up, but not wits.

Dr. Dwijesh Kumar Panda

Memory researchers Scott Small of Columbia University Medical Center reassures that “as age goes up, memory goes down “but not wits. Memory decline occurs in every one. Most memory loss is normal. Some people become part of the unlucky minority that develops Alzheimer’s disease or other forms of dementia. Alzheimer’s is expected to strike 34 million people globally by 2025 and 14 million in the U.S. over the next 40 years. Half of all people who reach age 85 will exhibit symptoms of the disease. Since U.S. life expectancy currently tops out at 80 for women and 75 for men, by the time the 85th birth day rolls around, you are not likely to be troubled by Alzheimer’s disease- or anything else. Memory is supposed to operate in the Hippocampus; a cashew shaped node of tissue sits deep in the temporal lobe of the brain. It is the gatekeeper of sensory information which subsequently moves to prefrontal cortex where it will be briefly held called as short-term memory.

The hippocampus begins to malfunction early in Alzheimer’s disease. Imaging studies have shown that people with Alzheimer’s typically have a smaller than average hippocampus. As the hippocampus shrinks, the pathway and the prefrontal cortex begins to degrade as well. The hippocampus also goes at least somewhat awry in normal memory loss. It is relatively stable in volume till about 60 years. As people get older, they have problems paying attention – a function controlled by the prefrontal cortex, which starts to diminish in size well before middle age. It also begins to use the brain’s fuel, glucose, less efficiently and loses about half its concentration of the neurotransmitter dopamine.

                                                Photograph of Dementia

 Researchers from the Institute in Stockholm who have been following over 1500 people for more than 35 years found a significantly lower rate of dementia, including Alzheimer’s, in those who exercise. Another study, of 2000 elderly men living in Hawaii, showed that those who walked two miles or more a day were half as likely to develop dementia as those who walked   a quarter mile or less. But physical activity is not all in improving memory. There is also what we eat. Blueberries zap free radicals (highly reactive atoms that can damage tissues) reverse aging, enhance cognition, and cause new neurons to grow. Similar benefits obtained from walnuts, which contain alpha-linolenic acid, essential omega-3 fatty acids. To maintain a sharp memory, one should strive for a diet that keeps belly fat down. A study of more than 6,500 people published in the journal Neurology showed that people who were over weight and had a large belly were 2-3 times as likely to develop dementia as those with normal weight and belly size. High blood glucose is one of the main contributors to age-related memory decline.
            
In older people, memory problems may also be the result of poor diet, vitamin deficiencies or glandular imbalances (all reversible with treatment) rather than the classic types of dementia associated with age. Even if a physician ultimately diagnoses Alzheimer’s disease- which is done by eliminating other possibilities rather than by a direct test, because none is available other than a brain biopsy. The mind-robbing disease is still incurable, and the drugs that are currently available only ease certain symptoms like anxiety, confusion and insomnia. Alzheimer’s is one of the hottest areas of scientific research. Scientists are continually identifying genes that appear to be involved in the growth of nerve cell killing plaques in the brain. Even if the disease is not curable, it may soon be more treatable than ever. Our ability to recall experiences is one of our most perishable powers. Why do we remember so much- and forget so much? The gray hair has wise brains.

References; - Time Magazine- Your Brain.

Dr. Dwijesh Kumar Panda, M.D., Ph.D. (Medicine)
Senior Scientist,Filariologist, Pathologist and
Microbiologist, M5/12 Acharya Vihar,BBSR
Contact No. 94384 70777..

Re-submitted to the Secretary, Odisha Bigyan Academy, Bhubaneswar, for favour
of publication in Science Horizon.