In 2002, Torkel Klingberg, a psychologist at Sweden’s Karolinska Institute, published a study involving 14 children with attention deficit hyperactivity disorder. All of the children were asked to spend a total of 10.5 hours, over five weeks, practicing computerized games that put demands on their working memory—their moment-by-moment attention and ability to juggle and analyze the objects of their attention.
Seven of the children played the games only at the beginner’s level; for the other seven, the games became progressively harder as the children got better. At the study’s end, the group who trained progressively not only improved on the games, but also on other measures of working memory. Their hyperactivity, as measured by head movement, lessened. And incredibly, even bizarrely by the standards of orthodoxy then holding sway, they also did much better on the Raven’s progressive matrices, long regarded as psychology’s single best measure of fluid intelligence. If the results were to be believed, the kids had gotten smarter.
At first scoffed at, the little study has since led to dozens of other studies (15 of them listed here) aimed at replicating and expanding its finding. It also quickly led Klingberg and the Karolinska Institute to form a company, Cogmed, to turn working-memory training into a business. The initial target market was children with ADHD, whose parents hoped to find something other than drugs to improve their children’s attention; but soon the market expanded to treatments for both adults and children with a variety of cognitive disorders. By 2010, in a step suggesting just how vast a business this brain training could be, Cogmed was sold to Pearson, the largest education company in the world.