Activities that keep the brain active, such as reading, writing and playing card games, may delay the precipitous memory declines that define dementia, a new study suggests.

Dementia is a decline in mental capabilities, especially memory and functioning, that can be caused by specific diseases such as Alzheimer's and Parkinson's, as well as stroke and infections to the brain.

While genetics are suspected to play a role in dementia, more and more studies are showing that lifestyle factors might also influence the severity of the problems.

The new study, detailed in the Aug. 4 issue of the journal Neurology, involved 488 people age 75 to 85 who did not have dementia at the start of the study. They were followed for an average of five years; during that time 101 of the people developed dementia.

At the beginning of the study, people reported how often they participated in six leisure activities that engage the brain : reading, writing, doing crossword puzzles, playing board or card games, having group discussions, and playing music.

For each activity, daily participation was rated at seven points, several days a week was rated at four points, and weekly participation was rated at one point. The average score was seven points total for those who later developed dementia, meaning they took part in only one of the six activities each day, on average.

The researchers then looked at the point when memory loss started accelerating rapidly for the participants. They found that for every additional activity a person participated in, the onset of rapid memory loss was delayed by 0.18 years, or about 9 weeks.

"The point of accelerated decline was delayed by 1.29 years for the person who participated in 11 activities per week compared to the person who participated in only four activities per week," said study author Charles B. Hall of Albert Einstein College of Medicine in Bronx, NY.

The results held even when the researchers factored in the education levels of the participants. Higher education has been linked to lower occurrences of cognitive decline in previous studies (though some studies have found the opposite connection).

Other aspects of a person's lifestyle have also been linked to fewer memory problems from dementia, Alzheimer's disease and cognitive decline from normal aging:

  • Those who can handle stress without becoming anxious may see fewer memory problems.
  • Exercise may keep older minds, as well as bodies, in shape by improving blood flow in the brain.
  • Searching the Internet is another activity that can keep the brain active and may be better than reading because of the range of choices it involves making.