Focus

Here's a tidbit from John Tierney's NYT Findings column, "Ear Plugs to Lasers - The Science of Concentration":

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When something bright or novel flashes, it tends to automatically win the competition for the brain’s attention, but that involuntary bottom-up impulse can be voluntarily overridden through a top-down process that Dr. Desimone calls “biased competition.” He and colleagues have found that neurons in the prefrontal cortex — the brain’s planning center — start oscillating in unison and send signals directing the visual cortex to heed something else.
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“It takes a lot of your prefrontal brain power to force yourself not to process a strong input like a television commercial,” said Dr. Desimone, the director of the McGovern Institute for Brain Research at M.I.T. “If you’re trying to read a book at the same time, you may not have the resources left to focus on the words.”
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Here are some tips from the author of "Rapt,” a guide to the science of paying attention, Winifred Gallagher.

Ms. Gallagher advocates meditation to increase your focus, but she says there are also simpler ways to put the lessons of attention researchers to use. Once she learned how hard it was for the brain to avoid paying attention to sounds, particularly other people’s voices, she began carrying ear plugs with her. When you’re trapped in a noisy subway car or a taxi with a TV that won’t turn off, she says you have to build your own “stimulus shelter.”

She recommends starting your work day concentrating on your most important task for 90 minutes. At that point your prefrontal cortex probably needs a rest, and you can answer e-mail, return phone calls and sip caffeine (which does help attention) before focusing again. But until that first break, don’t get distracted by anything else, because it can take the brain 20 minutes to do the equivalent of rebooting after an interruption. (For more advice, go to nytimes.com/tierneylab.)