American teenagers are getting far less sleep than they need, and their health, behavior and academic performance are suffering as a result.
This conclusion represents the evolving consensus of many sleep researchers who will be gathering tomorrow at the National Academy of Science for a workshop on the sleep needs of adolescents.
Their goal is to review the growing body of research on teenage sleep deficits and to explore its policy implications. The most pressing issue involves high school starting times--whether it makes biological and psychological sense to bring middle and late teens into school as dawn is just breaking.
"Sleep experts feel really strongly that high school timings are out of sync with the natural circadian rhythms of adolescents," said Michele Kipke, director of the academy's Board on Children, Youth and Families, which is hosting the Washington workshop.
"There is a belief that the research already done needs to be understood better by the general public and by the policy makers in education," she said.
Recent research into adolescent sleep patterns has consistently shown that most middle and late teens need nine hours of sleep, yet for biological reasons during this time in their lives they generally cannot go to sleep earlier than 11 p.m. With most high school starting times in the 7:15 to 7:45 a.m. range--as contrasted with starting times 30 minutes to an hour later a generation ago--the problem is obvious.
Some school districts have moved back their high school starting times in response to the sleep research--notably those in Minneapolis and some surrounding districts. But in other districts that have considered such a move, starting times remained early because of concerns about increased busing costs, shorter after-school sports practices or fewer opportunities for after-school jobs. Researchers say they have been frustrated by the limited public response to their findings.
"Since the amount of sleep a student gets correlates strongly with academic performance and social behavior, it's important for high schools to have later start times," said William Dement, director of the Sleep Disorders Center of Stanford University and a workshop panelist. Dement has been studying sleep and sleep disorders for 48 years.
"There is by now a huge reservoir of knowledge about the sleep patterns and needs of adolescents, but it's been dammed up by public ignorance and bureaucracy," he said. "I see a real parallel to cigarettes and smoking: We knew for years that it was bad for people to smoke, but it took a long time for that to get translated into social policy. Now we know that a chronic sleep debt has bad consequences, but we're really not doing much about it."
Research by Mary Carskadon, director of Brown University's Chronobiology and Sleep Research Laboratory has shown that circadian rhythms of teenagers are geared toward a later sleep time and later waking time than adults or younger children. These rhythms include the release of chemicals that encourage alertness or sleep.
In her more recent research, she monitored teenage "sleep latency"--the speed at which adolescents could fall asleep--in 25 students making the transition from middle school to high school.
To her surprise, she found that half of those 10th graders who were awakened for a 7:20 a.m. starting time showed brain patterns similar to those in patients with the sleep disorder narcolepsy. Specifically, when given the opportunity to sleep at 8:30 a.m., their brains quickly entered a REM (rapid eye movement) pattern associated with deep sleep. By contrast, most people would move into a different brain pattern, one that precedes deep sleep. In addition, 12 of the 25 students reached sleep-like states within three to four minutes--an extremely short period of time--in tests throughout the day.
"Basically, the brains of many of these kids were closer to being asleep than to being awake," said Carskadon, who will also speak at the workshop. "They had a large sleep debt, but were otherwise normal teenagers."
Additional research will be presented from Minneapolis, where high schools pushed their starting times back from 7:15 to 8:40 a.m. in 1997. According to Kyla Wahlstrom, associate director of the University of Minnesota's Center for Applied Research and Educational Improvement, the results have been largely positive. She said the results parallel those from suburban Edina, Minn., which changed start times in 1996 and which has seen an improvement in grades and general academic performance.
"The students report feeling better about themselves, falling asleep less in class, and being more alert when they do homework," Wahlstrom said. "We are also finding a definite trend in terms of better grades and better results on standardized tests." She said that researchers need a third year of academic results from Minneapolis before they can submit definitive results, but that "something positive certainly seems to be going on in the data."
Wahlstrom's group has also surveyed teachers and school administrators affected by the change, and found somewhat less support for the change. Many teachers in Minneapolis, for instance, said that the later start times made their commutes more difficult and took away important private time in the afternoon. However, Wahlstrom said that concerns about a possible decline in student after-school participation in sports, extracurricular activities and jobs has not occurred. Some students did complain they were getting worse after-school jobs because they were arriving later.
"Make no mistake, this is a difficult change for any community," she said. "But many of the worst community fears have not be realized, and there have clearly been improvements for many students in terms of academics and behavior."
Researchers say another common public hurdle to overcome has been the belief that teenagers don't go to sleep earlier because they are rebellious, because they're watching television or using the Internet, or otherwise deciding to stay up late.
"Some people just can't accept the fact that many teenagers are simply unable to fall asleep much before 11," said Stanford's Dement. "And there are certainly others who say we are trying to coddle adolescents or make excuses for their laziness. Our response is that research shows that adolescents need about nine hours of sleep, just like younger children, and that there are inevitable consequences if they don't get it week after week."
Rep. Zoe Lofgren (D-Calif.), who has introduced legislation that would encourage later high school start times, will also speak at the workshop. "We have to change this from a moral issue to a scientific issue," she said. "The science is telling us that later start times are much better for most teenagers, and I think we have to listen to that if we want our kids to learn to their fullest potential."
Locally, both Montgomery and Fairfax county public schools have explored the subject of sleep and school schedules, but after experiencing strong opposition decided not to change their 7:25 a.m. high school bell times. In last spring's report on school starting times, the Montgomery study group concluded that "verifiable research on this issue is preliminary." But the county Board of Education will revisit the issue on Nov. 9.
According to Cathy Colglazier, a high school English teacher on the Fairfax task force, her group tried to find ways to make starting times later, but ran into obstacles ranging from a dearth of bus drivers to opposition from coaches and others who work with students in the afternoon. And then there was the prospect of having to spend millions of dollars for new buses.
"We've seen the research, and we know from experience how tired and overstretched many students are," Colglazier said. "But there was a feeling [on the task force] that before we go out and spend $30 million on new buses, we wanted proof that later starting times will definitely makes things better."
Federal and local policy makers have been invited to the NAS sleep workshop, and members of the public can also attend. For information, call 202-334-1937.
Teachers's Choices of Ideal School Starting Times
Percentage, by time choice
7:00 a.m. 0.7%
SOURCE: Center For Applied Research and Educational Improvement