Articles
Genes
Several genes have been implicated in Alzheimer's, but the big one is the e4 allele of the ApoE gene (on chromosome 19). This variant is found in about a quarter of the population.
Having it doesn't mean you are foreordained to develop Alzheimer's, but it certainly increases the risk substantially. The risk goes up considerably more if both of your genes are the e4 variant (remember you inherit two: one from each parent).
Most mnemonic strategies use visual images. But as I say in The myth of imagery, while there is no doubt that imagery can be an effective tool, there is nothing particularly special about it. The advantage of imagery is that it provides an easy way of connecting information that is not otherwise readily connected. However, providing verbal links can be equally effective.
Brain tissue is divided into two types: gray matter and white matter. These names derive very simply from their appearance to the naked eye. Gray matter is made up of the cell bodies of nerve cells. White matter is made up of the long filaments that extend from the cell bodies - the "telephone wires" of the neuronal network, transmitting the electrical signals that carry the messages between neurons.
The volume of gray matter tissue - a measure you will see cited in various reports - is a measure of the density of brain cells in a particular region.
A study1 of nearly 2000 older adults has found that eating a Mediterranean diet was associated with less risk of developing mild cognitive impairment or of transitioning from MCI to Alzheimer's disease. The third with the highest scores for Mediterranean diet adherence had a 28% lower risk of developing MCI compared to the third with the lowest scores, and of those who already had MCI, those with the highest scores for Mediterranean diet adherence had a 48% less chance of developing Alzheimer’s.
The thing to remember about Ericsson’s famous expertise research, showing us the vital importance of deliberate practice in making an expert, is that it was challenging the long-dominant view that natural-born talent is all-important. But Gladwell’s popularizing of Ericsson’s “10,000 hours” overstates the case, and of course people are only too keen to believe that any height is achievable if you just work hard enough.
The much more believable story is that, yes, practice is vital — a great deal of the right sort of practice — but we can’t disavow “natural” abilities entirely.
Most mnemonic strategies are based on imagery. There is no doubt that imagery can be an effective tool, but there is nothing particularly special about imagery. The advantage of imagery is that it provides an easy way of connecting information that is not otherwise readily connected. However, providing verbal links can be equally effective.
The evidence that diet, physical exercise, and mental stimulation all help prevent age-related cognitive decline and reduce the risk of mild cognitive impairment and Alzheimer’s, is now very convincing.
Studies of mice and (rather intriguingly) beagles, have provided evidence that ‘enriched’ environments — ones that provide opportunities for regular exercise and mental stimulation — reduce or prevent age-related cognitive decline, and reduce the risk of Alzheimer’s.
Most people find numbers — phone numbers, personal identification numbers, dates, and so on — more difficult to remember than words. That is, of course, why businesses try to get phone numbers that correspond to some relevant word. The system whereby this is possible — the linking of certain letters to the different digits on a telephone calling pad —is a kind of coding mnemonic. Basically, coding mnemonics are systems that transform numbers into words.
Prevalence of dementia
Dementia is estimated1 to afflict over 35.5 million people worldwide -- this includes nearly 10 million people in Europe, nearly 4.4 million in North America, nearly 7 million in South and Southeast Asia, about 5.5 million in China and East Asia and about 3 million in Latin America.