科学美国人60秒 SSS 2013-09-26（在线收听）

 The midday nap is preschool tradition,but is it necessary?some preschool plan to eliminate this down time to fit in more teaching,which could come the expensive learning,because the study suggests that the news may help kids to retain the information they learned the early in the day,the work is published in plus one,to see how naps affect the academic performance,researches taught 40 preschoolers between the ages of 3 and 6 to perform a memory task,after a few hours of break time the children neither stayed awake or got nap, sleep for average for  77 minutes, although napping make no significant difference to feeling this sleepiness it did help enhance memory, when tested later in the day,student who had rested perform better,even next day,the children who have napped after initial lessons still retained more information,the benefit was greatest for students who took naps regularly,not just during a study,which suggest schools may want to keep sleep on the syllabus.