To examine the effect of speed of processing training on dementia incidence, community dwelling adults aged 65 years or older without dementia were recruited and randomized to the speed of processing training or nocontact control. Participants randomized to the speed of processing training received computerized, processbased speed of processing training, which involved perceptual practice exercises designed to increase the amount and complexity of information participants could quickly process. Participants completed up to 14 training sessions over a 5week period. Participants in both the speed training and control groups were then followed for 10 years. Dementia incidence during the 10 years of followup among participants in the control group, participants in the speed training group who received 0-10 training sessions, and participants in the speed training group who received 1114 training sessions is shown below: Dementia Incidence Group _-IE- Speed of processing training with 010 49 355 training sessions Speed of processing training with 1114 24 270 training sessions