Study author Frederick W. Unverzagt from Indiana University's school of medicine, said, "We would consider this a relatively small dose of training, a low intensity intervention. The persistence -- the durability of the effect was impressive."
The researchers, from IU, the University of South Florida, Pennsylvania State University and Moderna Therapeutics, examined 2,808 healthy adults aged 65 years and older and were randomly assigned one of four treatment groups.
The first group received instructions and practice in strategies to improve memory of life events and activities.
The second group received instructions and practice in strategies to help with problem solving and related issues.
The third group received computer-based speed of processing exercises, designed to increase the amount and complexity of information they could process quickly.
The fourth was the controlled group, whose members did not participate in any cognitive training program.
Initial training consisted of 10 sessions lasting about an hour, over a period of five to six weeks.
The participants were assessed immediately after training and at one, two, three, five and 10 years after training.
About 1,220 participants completed the 10-year follow-up assessment.
The results suggested that about 260 participants developed dementia.
The risk of developing dementia was 29 percent lower for participants in speed of processing training than for those who were in the control group.
Moreover, the benefits of the training were stronger for those who underwent booster training.
Dr. Unverzagt noted that the speed of processing training used computerised "adaptive training" software with touch screens.
The research is published in journal of the Alzheimer's Association. (ANI)