Washington ? Just in time for the holidays, some medical advice most people will like: Take a nap.

Interrupting sleep seriously disrupts memory-making, compelling new research suggests. But on the flip side, taking a nap may boost a sophisticated kind of memory that helps us see the big picture and get creative.

Good sleep is a casualty of our 24/7 world. Surveys suggest few adults attain the recommended seven to eight hours a night.

Way too little clearly is dangerous: Sleep deprivation causes not just car crashes but all sorts of other accidents. Over time, a chronic lack of sleep can erode the body in ways that leave us more vulnerable to heart disease, diabetes and other illnesses.

But perhaps more common than insomnia is fragmented sleep — the easy awakening that comes with aging, or, worse, the sleep apnea that afflicts millions, who quit breathing for 30 seconds or so throughout the night.

Indeed, scientists increasingly are focusing less on sleep duration and more on the quality of sleep, what’s called sleep intensity, in studying how sleep helps the brain process memories so they stick.