In fact, it may help prevent cognitive decline like that other evil of the modern age: exercise.
In addition to exercise and good nutrition for the aging brain, using the computer to keep your mind active could prevent mild cognitive impairment (MCI). This form of cognitive decline falls in between normal age-related memory problems and the beginnings of Alzheimer's disease.
It turns out that both exercise and computer use each have protective effects - but the two together are even better.
Researchers at the Mayo Clinic studied 926 people in Minnesota between the ages of 70 and 93. They had them fill out questionnaires about the kinds of physical activities they engaged in, including aerobics, strength training, yoga, hiking, swimming, and others. They also asked the participants about how often they took part in mentally stimulating activities, like playing games, reading, play music, arts and crafts, and using the computer. The team was particularly interested in computer use, given its prevalence across all generations.
It turns out that both exercise and computer use each have protective effects - but the two together are even better. Of the people who neither exercised nor used a computer, about 20 percent had normal cognition, and almost 37 percent had mild cognitive impairment. But people who used computers and exercised regularly were in much better shape: 36 percent were cognitively normal, while only 18 percent had MCI.