The Science Behind 'Brain Training'

Increasing fluid intelligence has proven beneficial for people diagnosed with ADHD, and selling memory improvement is a big business. Are the claims overheated? 

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.

“Cogmed is a leader in the emerging field of evidence-based cognitive training,” the company states on its website. “We have scientifically validated research showing that Cogmed training provides substantial and lasting improvements in attention for people with poor working memory—in all age groups. That makes Cogmed’s products the best-validated products on the market.”

Aren’t claims like this rather overheated? I posed that question to Klingberg at Joe Coffee, a tiny, crowded coffee shop on West 23rd Street in Manhattan, where he was in town to give a talk at Columbia University. He wore a black leather jacket and a momentary scowl, having heard such critical questions many times before.

“Yeah, well,” he said with a shrug. “We did start to do research in 1999. Of course you can say that we still don’t have—we should wait another 10 years until we have thousands of participants. This is a general problem with cognitive training studies that we don’t have these huge studies that drug companies have. On the other hand, this is not something that is dangerous.”

He pointed out that Cogmed claims only that it can improve working memory, not fluid intelligence per se—even though many studies have found that working memory and fluid intelligence are closely related.

“What we see, over and over again,” he said, “is improvement of working memory and also of attention, including attention in everyday life. This is not everything, but it’s good enough for me if we can have that. Working-memory problems and attention problems are huge for many children and adults. Right now I don’t have any financial interest in Cogmed anymore. The influence I have had over Cogmed has been to make them very cautious. They don’t make claims about rejuvenating your brain or improving intelligence.”

I asked him to describe exactly what kind of computerized training tasks Cogmed offers.

“There are 12 tasks,” he said. “They’re all visuospatial. The role of attention in working memory almost always has a spatial dimension. When you’re paying attention—even when you’re paying attention to me talking here in this café—there’s a spatial component. When there’s a loud noise, you might shift your attention to where it’s coming from. Being able to maintain your spatial focus on me is important for you right now. Even though it’s words coming from me, there’s an important component of space. So if you can improve the stability of that spatial aspect, you will be better at visuospatial tasks and be better at keeping your focus on me rather than on that noise over there.”

Still wanting a better sense of the exercises Cogmed offers, I scheduled a meeting with a clinical psychologist, Nicole Garcia, who offers the training just a few miles from my home in Montclair, New Jersey. She allowed me to sit down at her computer to play a handful of the games. (She emphasized that Cogmed calls them “training tasks,” not games. But they looked like games to me.)

I clicked one called Hidden, which showed a standard numeric keypad, the kind used on cell phones and calculators. The keypad was hidden while a man’s voice recited a short list of numbers. When his list was complete, the keypad reappeared, and I was supposed to click on the list—in reverse order. Another game showed a circle with nine smaller circles strung along it like carriages on a Ferris wheel. As the big circle slowly rotated in a clockwise direction, the little circles lit up in a random sequence. Once the sequence was completed, I had to click on the little circles in the same order.

All of the games were easy on the first pass, but immediately grew hard enough—meaning that the sequence to be remembered grew longer and was presented faster—that I began making mistakes.

Having offered Cogmed to a few dozen of her patients, as young as six and as old as 63 (including a successful attorney whose ADHD was diagnosed in her forties), Garcia said she’s convinced of its benefits, sometimes in combination with medication and sometimes on its own. And at a total cost to families of about $2,000 for the 25 sessions, she said, it compares favorably with many other kinds of ADHD treatments.

Where Cogmed beats all other forms of cognitive training is in the number of published, randomized clinical trials demonstrating its benefits and the number of trials still under way, led by independent researchers at leading institutions without any commercial connection to the company.

Julie Schweitzer, director of the ADHD Program at the University of California in Davis’s MIND Institute, conducted a randomized study of children diagnosed with ADHD.  When published in July 2012 in the journal Neurotherapeutics, Schweitzer’s study found that children in the placebo group spent just as much time off-task at the end of the study as they had at the beginning, but those who trained on Cogmed sharply increased the amount of time they spent doing school work.

Children who have survived cancer are another group often in need of cognitive rehabilitation. “Somewhere around 20 to 40 percent of children treated for leukemia will end up with cognitive changes over time,” said Kristina K. Hardy, a neuropsychologist at Children’s National Medical Center in Washington, D.C. “For those treated for brain tumors, the figure is conservatively around 60 to 80 percent.”

What distinguishes these young survivors from most others seeking cognitive rehabilitation is that the effects of radiation or chemotherapy on the brain become apparent only with the passage of time. Immediately following treatment, a recent study found, survivors of acute lymphoblastic leukemia showed no significant change in their verbal IQ scores, but by early adulthood, their scores had dropped by an average of 10.3 points.

In 2012, Hardy reported the results of a pilot study comparing Cogmed to a placebo form of computerized. Among 20 children who had survived either brain cancer or leukemia, those who trained with Cogmed saw substantial improvements compared to the placebo group on their visual working memory and in parent-rated learning problems.

Most recently, children with Down syndrome have been shown to benefit from Cogmed. “Following training,” concluded a study published last June, “performance on trained and untrained visuospatial short-term memory tasks was significantly enhanced for children in the intervention group. This improvement was sustained four months later. These results suggest that computerized visuospatial memory training in a school setting is both feasible and effective for children with Down syndrome.”

Brian Skotko, co-director of the Down Syndrome Program at Massachusetts General Hospital, told me, “If Cogmed was a drug, everyone would call this study groundbreaking.”

Not all studies of Cogmed have been positive. A large one published in October found little benefit. But as Klingberg has written in defense of Cogmed in particular and working-memory training in general: “Working memory training is still a young field of research. As with all science, no single experiment explains everything, and results are never perfectly consistent … Many questions remain. But there is no going back to the notion that working memory capacity is fixed.”

This post is adapted from Dan Hurley's Smarter: The New Science of Building Brain Power.