Old age inevitably affects cognitive flexibility and working memory capacity, which is a growing problem for the aging society and the individual. Cognitive training can slow down decay, but is experienced as aversive. In contrast, dedicated computer games may protect against cognitive decline, while being entertaining. Unfortunately, there is an alarming lack of effectiveness studies of these games. The current project performs a randomized controlled intervention study into the trainability of working memory capacity and cognitive control in older adults (age 65-75 years). Behavioral and psychophysiological measures are recorded before and after a ten-week gaming period, and in follow-up sessions.