Even naps are beneficial, according to a Harvard study in which subjects who took a 90-minute snooze after learning a task performed 50 percent better over a 24-hour period than the napless group.

• 根据哈佛大学的一项研究表明，即便是打个盹也会对记忆有帮助。受测者学习后打盹90分钟的人们在24小时内要比那些没有打盹的人群表现更好。