This study, which focused on mental activities, involved 1,076 people with an average age of 80 who were free of dementia. Participants underwent yearly memory exams for about five years. They reported how often they read the newspaper, wrote letters, visited a library and played board games such as chess or checkers. Frequency of these mental activities was rated on a scale of one to five, one meaning once a year or less and five representing every day or almost every day.
"The results suggest a cause and effect relationship: that being mentally active leads to better cognitive health in old age," said Wilson.
The results showed that people's participation in mentally stimulating activities and their mental functioning declined at similar rates over the years. The researchers also found that they could predict participants' level of cognitive functioning by looking at their level of mental activity the year before but that level of cognitive functioning did not predict later mental activity.