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This is Scientific American sixty seconds science. I am cythina Graber. This will just take a minute.

You are lying in a hammock by a breezy shore. The hammock rocks softly back and forth¹.in no time. It turns out that not just the relaxation² of being on vaction that is bringing on sleep.It is the rocking hammock.Not by a huge surprize, babies get rocked to sleep,but researchers want to know how rocking works. They recruited twelve healthy males all good sleepers³. Each volunteered twice to take afternoon nap in a dark room on a custom made bed that could rock.For one nap, the bed was still for the other,it rocked gently.All the men fell asleep faster when they swayed.And scientists monitored the men's brain activites during all the naps. They found that the rocking increased the duration of what's called N2, a non run stage that accounts for about half of good night's sleep.Rocking also increased the deep sleep associated with brain activity, so called slow oscillation as well as bursts of actionns called sleep spindles.Researchers published in the journal of current biology. The next step is to find out whether rocking can help treat sleep disorders⁴.Meanwhile, in some nua*, can always try a hamic.