“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.)