A Brain Game That Works
If you habitually misplace your keys or forget passwords, there may be hope for you yet. A new study from Johns Hopkins researchers suggests that certain types of brain training can strengthen working memory.
The growing popularity of brain games has raised a question in the science community: Do these things actually work? Previous studies have had mixed results, sparking a debate about whether brain training truly sharpens cognitive capacity. “The thing that I think people find frustrating is they read one study that says cognitive training works, and they read another study that says it doesn’t work,” says Susan Courtney, a Hopkins neuroscientist and one of the authors of the study. “It’s not that nothing works, or that everything works. It’s that some things work.”
Here, the Hopkins research team compared the effectiveness of two popular tests and found that one of them was significantly better at improving memory and attention, contradicting claims that all cognitive training is ineffective. Researchers assembled three groups of young adults. All of them took an initial round of cognitive tests to determine baseline working memory, attention, and intelligence. They also got an electroencephalogram, or EEG, to measure brain activity. Then they were sent home to practice brain tasks on the computer for 30 minutes, five days a week, over several weeks.
One group used a leading brain exercise known as the dual n-back. Another group performed a different common exercise known as complex span. The third, a control group, practiced a task not meant to improve working memory.
The team discovered that the group using the dual n-back test showed a 30 percent improvement in their working memory, nearly double the gains made by the group practicing the complex span. The dual n-back participants also showed changes in brain activity in the prefrontal cortex, the region responsible for decision making and complex cognitive skills such as planning. No one got smarter, however; IQ remained the same for all groups.
The dual n-back is a memory test in which people must recall increasingly complex sequences of visual and auditory stimuli. You may, for instance, be shown a series of squares as they pop up one by one in different spatial locations on your computer screen. Your job is to remember where the previous squares appeared, a bit like a classic game of Memory. The audio portion uses alphabet letter sounds to create patterns that you also must remember. As the test advances, you must remember squares and letters two, three, even four rounds back. “That task really depends on this ability to keep changing what is important and replacing it with something new that is now important,” Courtney says. “There’s something about sequencing and updating that really taps into the things that only the prefrontal cortex can do, the real-world problemsolving tasks.”
In the complex span exercise, testers also had to remember items in a sequence—with a distraction thrown in—but they weren’t required to continually update the items in their mind. “If you look at performance and brain activity,” Courtney says, “the dual n-back group seemed to result in better interaction between the front and back of the brain necessary for people to hold on to what’s important and suppress what’s not important.”
That’s key because some brain experts believe that a strong working memory isn’t so much about your brain’s capacity but about your ability to remember the right information to complete a task while disregarding nonuseful data.
Courtney says the next challenge for the research team is to pinpoint why the dual n-back test is so effective and then design an even better exercise to strengthen cognitive skills. “The biggest lesson here was that—yes—intensive training strengthens cognition and the brain, but we still don’t understand why and how,” Courtney says. “We can’t just jump onto a video game and expect that’s going to cure all our cognitive problems. We need more targeted interventions.”
Insights from further research could be used to develop a consumer-facing application geared, for instance, toward slowing age-related memory loss. “There is potential for being able to train the brain,” Courtney says, “and we’re working on figuring out the best way to do that.”
Hopkins researchers compared the effectiveness of two popular brain games and found that the dual n-back test resulted in a 30 percent improvement in working memory.