Staying up an hour or two past bedtime makes it far more difficult for children to learn, say scientists who deprived youngsters of sleep and tested whether their teachers could tell the difference.
If parents want their children to thrive academically, “getting them to sleep on time is as important as getting them to school on time,” said psychologist Gahan Fallone, who conducted the research at Brown Medical School.
The study, released yesterday at an American Medical Association science writers meeting, was conducted on healthy children who had no evidence of sleep- or learning-related disorders.
Difficulty paying attention was among the problems the youngsters faced — raising the question of whether sleep deprivation could prove worse for people with attention deficit hyperactivity disorder.
Mr. Fallone is studying that question, and suspects that sleep problems “could hit children with ADHD as a double whammy.”
The researchers at Brown set out to test whether teachers could detect problems with attention and learning when children stayed up late.
They recruited 74 6- to 12-year-olds from Rhode Island and Massachusetts for the three-week study.
For one week, the youngsters went to bed and woke up at their usual times. They got nine to 91/2 hours of sleep a night.
Another week, they were assigned to spend no fewer than 10 hours in bed a night. And another week, first- and second-graders were in bed no more than eight hours and the older children no more than 61/2 hours.
Teachers weren’t told how much the children slept or which week they stayed up late, but rated the students on a variety of performance measures each week.
The teachers reported significantly more academic problems during the week of sleep deprivation, the study concluded.
Students who got eight hours of sleep or less were more forgetful, had the most trouble learning new lessons and had the most problems paying attention, said Mr. Fallone, who is currently at the Forest Institute of Professional Psychology in Springfield, Mo.
So how much sleep do children need? Recommended amounts range from about 10 to 11 hours a night for elementary-school students to 81/2 hours for teens.