COLUMBUS, Ohio - The impact of a form of meditation known as "mindfulness" is growing.

It's being used by U.S. Marines, tech geeks at Google, and prison inmates. An Ohio congressman is pushing for its wider use in U.S. schools and hospitals, and in Washington.

As mindfulness practice spreads, critics wonder whether it's simply traditional Buddhist meditation repackaged and commercialized for a secular audience.

Its champions say the physical benefits are proven by a growing body of brain science. Studies show mindfulness practice reduces stress as well as the symptoms of certain diseases and conditions.

It involves dwelling on your own breathing, paying attention to areas of the body and experiencing periods of silence in order to concentrate on the present rather than the worries of yesterday and tomorrow.