One particular type of mental exercise may succeed at doing what nothing else has before: putting off dementia.

A new, 10-year study showed that speed training—computer exercises that get users to visually process information more quickly—beat out memory and reasoning exercises, two other popular brain-training techniques. Researchers found that a total of 11 to 14 hours of speed training has the potential to cut by as much as 48% the risk of developing dementia 10 years later.

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