From Sydney Morning Herald -Australia
...It is the revenge of the nerds. But unlike in the 1980s B-movie, the real-life version takes a little longer to reach its triumphant finale. Research shows young people with high IQs and many out-of-school interests are less likely to develop dementia when they are old.
The findings support the theory that the brain develops "hardware reserves" early in life, which protect against later mental deterioration.
US researchers looked at the academic history of 396 elderly people, with an average age of 75, who were all graduates of the same high school in the mid-1940s. They cross-referenced the subjects' IQs as adolescents and the number of out-of school activities they did with their current mental state.
They found the risk for dementia and its precursor, mild cognitive impairment, for people who took part in two or more extracurricular activities a year was about one-third that of those who took part in fewer than two activities a year. Those with a higher IQ had half the risk of developing dementia.
"The evidence supports the possible protective role of activity levels in avoiding a diagnosis of dementia," said Professor Helen Christensen, the director of the Australian National University Centre for Mental Health Research.
The study authors, writing in the Journal of the American Geriatrics Society, postulated that the protective effect of IQ and activity might be due to the "reserve theory", which suggests that some people are able to withstand a greater amount of brain damage before reaching the threshold for dementia. The research also suggested that teenagers with a lower IQ could reduce their vulnerability to dementia by taking up more activities.
But Mitchell Ferguson, 9, did not take up his favourite extracurricular activity, chess, to offset his risk of developing dementia in later life. He plays the game because he loves it, so much so that he spent the first day of his school holidays at a chess coaching clinic in Lidcombe, with 54 other children aged six to 14.
Richard Gastineau-Hills, the tournament co-ordinator for the NSW Junior Chess League, which organised the clinic, said chess combined brain "exercise" with social activity.
"I think a lot of them like the competitive aspect of it, and meeting other players," he said.
Mitchell agreed that chess was challenging and interesting, but said his motivation was less noble: he wanted revenge on his uncle, whom he lost to last time they played.