A study published by Proceeding of the National Academy of Science on Tuesday finds napping increases the ability to learn in preschool children by boosting their memories. Dr. Rebecca Spencer of University of Massachusetts Amherst who led the research tells the Healthy Lifestyle of VOATibetan Service that those who didn’t take nap forgot 15 percent of the information they had learned in the morning. The study also found the quality of the nap plays bigger rule. “It looks like it wasn’t exactly how long they napped that made difference, but rather the quality of the nap,” Dr. Spencer says. However, she also says most kids can nap about 70 minutes. Dr. Spencer and her team recruited more than 40 kids between ages three and five, teaching them a “visual-spatial task”, they checked how much the kids remembered of it after their nap. The effect of missing a nap remained in the following day, she says. Even after a night’s sleep, the kids who had not taken the nap in the previous day still had lesser cognitive ability about the game they had learnt the day before.