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Fyodor Dostoevsky, the 19th Century Russian author, once famously challenged his brother to try out a strange task: Don't think about a polar bear right now. “Try to pose for yourself this task: not to think of a polar bear, and you will see that the cursed thing will come to mind every minute,” Dostoevsky writes in “Winter Notes on Summer Impressions.”

Since then, people have puzzled over what happens in the brain when we try intentionally to ignore things. Can we actually succeed in ignoring certain information -- and improve our focus on everything else? Or does trying to ignore something actually divert the brain toward that thing, sucking up brain space like Dostoevsky's polar bear?

In the past, psychological research has been divided. But a new paper from researchers at Johns Hopkins University reconsiders that debate, and suggests that learning to ignore certain things is a powerful tool for helping people focus.

You can try the basic task for yourself with this video quiz below. Does learning what to ignore help you speed up your search?

Can you find the 'T'? (Johns Hopkins University)

People obviously can find something more quickly when they know what it looks like -- their car keys, a familiar person in a crowd. But this research suggests that people can also find something more quickly and efficiently when they know what it doesn’t look like.

The research has implications for people who spend their careers scanning and searching through visual information, like radiologists looking for an unusual blob in an X-ray, or airport security personnel checking scans of luggage. But it also has potential implications for people learning to ignore everyday distractions and more efficiently concentrate at work or school -- or just find their car keys.

In their experiments, the Johns Hopkins researchers had people search a computer screen for specific letters in specific colors, a slightly different setup from the video above. Some people were given information about a color or a letter that they would be able to ignore while they searched for the target, while others were given no information.

Initially, being given information about what to ignore slowed people’s responses down, says Corbin Cunningham, the lead author on the study. But when the color of the non-targeted letter stayed the same through several trials, people quickly learned how to use that information. After a short time, people who were given information about a color or a letter to ignore were able to find their target letter faster than the other group.

The researchers repeated the experiment with a larger group of subjects and a much greater number of things to choose from -- 12 capital letters. In some trials, half of the letters were one color that participants were told they could ignore. The people who were taught to ignore letters completed these trials much faster than those who were not given information about what to ignore, as well as those who were told to ignore fewer letters. “The cost of ignoring goes away much more quickly when you can ignore multiple items,” Cunningham says.

He explains that the study helps show how the brain’s ability to suppress distractions -- what psychologists call “inhibition” -- works. The study suggests that the ability to pay attention to something is driven by inhibition, what Cunningham calls “the dark side of attention.” It might seem counterintuitive, but the reason you’re able to find or focus on a certain object is not just because of the attentive effort you’re exerting on that object, but largely because of your brain's ability to block out everything else.

So what kind of implications does this have for people who are struggling to find their car keys or focus on their work at a noisy, busy coffee shop?

Although the real-world implications of the research aren’t clear, Cunningham says the general phenomenon could support a strategy of actively trying to ignore things that bother you, rather than continuing with your work while you passively ignore them. First, stop and acknowledge what's distracting you, then make a concerted effort to block it out. That may help improve your focus. As the study suggests, this may be a process you can learn to do better over time.

Many famous and prolific people say that one secret to their success has been learning to ignore the small stuff, to make space for deep and efficient mental activity. One example is Richard Feynman, the Nobel-winning physicist, as computer science professor Cal Newport writes in a blog entry called, "Richard Feynman Didn't Win a Nobel By Responding Promptly to E-mails." In an interview, Feynman said:

“To do real good physics work, you do need absolute solid lengths of time…if you have a job administrating anything, you don’t have the time. So I have invented another myth for myself: that I’m irresponsible...I tell everyone I don’t [do] anything. If anyone asks me to be on a committee for admissions, ‘no,’ I tell them: I’m irresponsible.”

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