Editors’ note: We’re resurfacing this story from the archives to help you train your mind.

MEDITATION and mindfulness: the words conjure images of yoga retreats and Buddhist monks. But perhaps they should evoke a very different picture: a man in a deerstalker, puffing away at a curved pipe, Mr. Sherlock Holmes himself. The world’s greatest fictional detective is someone who knows the value of concentration, of “throwing his brain out of action,” as Dr. Watson puts it. He is the quintessential unitasker in a multitasking world.

More often than not, when a new case is presented, Holmes does nothing more than sit back in his leather chair, close his eyes and put together his long-fingered hands in an attitude that begs silence. He may be the most inactive active detective out there. His approach to thought captures the very thing that cognitive psychologists mean when they say mindfulness.

Though the concept originates in ancient Buddhist, Hindu and Chinese traditions, when it comes to experimental psychology, mindfulness is less about spirituality and more about concentration: the ability to quiet your mind, focus your attention on the present, and dismiss any distractions that come your way. The formulation dates from the work of the psychologist Ellen Langer, who demonstrated in the 1970s that mindful thought could lead to improvements on measures of cognitive function and even vital functions in older adults.

Now we’re learning that the benefits may reach further still, and be more attainable, than Professor Langer could have then imagined. Even in small doses, mindfulness can effect impressive changes in how we feel and think — and it does so at a basic neural level.