The research on the sleep needs of adolescents is a relatively new field—but one that seems to be growing in both quantity and quality and in the attention and interest given to it.

As a way to provide some background for all interested stakeholders in the Walled Lake Public Schools, this paper presents an annotated bibliography and brief responses to five essential questions about the sleep needs of adolescents:

1. How much sleep do adolescents need?

2. What are the influences on adolescent sleep patterns?

3. What are the influences on adolescent sleep problems and disturbances?

4. What are some common consequences of insufficient sleep?

5. What is the relationship between adolescent sleep and school start times?

There are numerous other questions that may well come to mind (e.g.: Why do some teenagers seem to be able to overcome sleep deprivation with a strong work ethic? Why is the school responsible for adolescents getting adequate sleep; isn’t this a parental responsibility?). The five suggested questions provide a substantial beginning place for our district’s activities to help us all become more sensitive to and informed about the special sleep issues of adolescents.

There are a number of individuals and institutions whose research focuses on sleep needs of children, adolescents, and adults. An extensive annotated bibliography is attached here. Some names, however, stand out in the literature and for those looking for a place to begin, we recommend Mary A. Carskadon, a professor of psychiatry and human behavior at the Brown University School of Medicine, who writes extensively on adolescent need for sleep; Kyla L. Wahlstrom, the associate director of the Center for Applied Research and Education Improvement (CAREI) at the University of Minnesota, Minneapolis, who helps pull together what is known about adolescent sleep needs with some of the school policy/program concerns that might result from that knowledge; and Ronald E. Dahl, M.D., an associate professor of psychiatry and pediatrics at the University of Pittsburgh Medical Center, who helps link issues of sleep and emotional regulation in adolescents. Also, papers published by CAREI and by the National Sleep Foundation provide a wealth of information for schools, parents, and adolescents themselves on this important issue.

Full texts of all sources referenced in this article are available on loan from the Staff Development Office.

1. How much sleep do adolescents need?

According to research first done in the mid 70’s and still considered valid today, adolescents need 9 hours and 20 minutes of sleep each night to be optimally functional the next day. A longitudinal study begun in 1976 at the Stanford University summer sleep camp attempted to examine the number of hours of sleep boys and girls ages 10, 11, and 12 required each night. The subjects came to the sleep camp for a 72-hour period each year for five or six years. One of the conclusions of the study was, regardless of age, all adolescents required the same number of hours of sleep each night. The adolescents in the study discovered as they matured, it became more difficult for them to fall asleep and wake up at the early times of their younger peers. (Carskadon, 1999; Graham, 2000)

A report from the results of a sleep habits survey administered to more than 3,000 Rhode Island 9th to 12th graders revealed that the median amount of sleep reported from the group was 7.5 hours a night. One quarter of the group reported sleeping 6.5 hours or less. For two-thirds of the students bedtime was after 11:00 PM on school nights and 91% rose at 6:30 AM or earlier. The findings from this survey reveal that for these young people, their sleep habits – both the number of hours and the sleep/wake times are not in keeping with healthy sleep habits.

In conclusion, adolescents need 9 hours and 20 minutes of sleep each night to function at their best during the day. Due to a change in biological rhythms experienced during puberty, an adolescent’s body clock is set to naturally fall asleep later in the evening wake and later in the morning than when they were younger. In actuality it appears teens sleep only 7.5 hours or less a night. Often hindering adherence to the natural patterns of the body’s sleep needs are the established early start time for high schools and the extended day schedules chosen by many teens.

Key Findings:

• As teenagers move through the teen years, they need the same amount of sleep as when they were younger but their lifestyle tends to cause them to become sleep deprived.
• Teens need nine hours of sleep each night to avoid behaviors associated with sleep deprivation.
  
• The adolescent’s circadian rhythm means he or she will feel awake later into the evening (through midnight) and needing to wake at a later hour in the morning.
  
  

(Center for Applied Research and Educational Improvement, 1998)

2. What are the influences on adolescent sleep patterns?

Influences on adolescent sleep patterns fall into two distinct categories: Intrinsic or biological influences and external or social influences.

Intrinsic Influences

Circadian rhythm is the human biological clock running on a 24-hour cycle that influences when and how much we sleep. These rhythms are governed by the alternation of light and darkness and are controlled by the hypothalamus. Circadian rhythms control REM (rapid eye movement) sleep within the sleep period. REM sleep occurs at the beginning and end of the sleep cycle and lasts for 1 ½ to 2 hours. This is the time the brain transfers information from short term to long-term memory. It is a very important part of the sleep cycle that should not be interrupted.

The second of the internal systems is the sleep/wake homeostasis system. This system monitors the amount of sleep and wake time a person has during each 24-hour period. Simply stated sleep/wake homeostasis is the biological pressure either for sleep, after having been awake for a long time, or for waking after having been asleep for a period of time. That is – the longer one has been awake, the greater the need for sleep. And vice versa. Laboratory measures can chart the sleep/wake homeostasis. (Carskadon, 1999)

A third bodily function that influences sleep patterns is the production of the hormone Melatonin. When it is time to sleep, Melatonin secretions increase preparing the body for rest and then decrease when it is time to wake. Mary Carskadon’s research with adolescent boys and girls confirmed they experience a later onset of Melatonin secretion at night, as they get older well as a later decrease in the morning. This too confirms the theory that adolescents naturally sleep at later times than children and adults. (Graham, 2000)

External Influences

Academics, sports, extra-curricular activities, family and social lives, part-time jobs, etc. are all external activities that influence the sleep patterns of adolescents. Mary Carskadon, Professor of Psychiatry and Human Behavior Brown University, School of Medicine reports that during the adolescent years academic requirements, social obligations, and opportunities for work expand. Some young people on sports teams spend as many as 20 hours at practice and games and are not getting enough sleep. High schools, for a majority of American students, have early morning starting times which conflict with the delayed phase sleep patterns of adolescents by interrupting the important REM sleep. (Quoting Carskadon in Graham, 2000)

3. What are the influences on adolescent sleep problems and disturbances?

Adolescents often experience “conflicts between physiologically driven sleep

needs and patterns and the behavioral and psychosocial factors influencing sleep.”

(Carskadon, 2002) The school schedule has a major influence on adolescent sleep. Between the ages of 10 and 17 weekday bedtime gets later, while rising time is earlier due to school start times. Although research reveals adolescents need the same amount of sleep as when they were young children, they actually get less and less. The influences on sleep patterns seem to vary widely depending on family composition, cultural background, socio-economic scale and values. While some of these influences on sleep patterns serve to promote healthy development, others predispose adolescents to even greater risks.

Some influences on adolescent sleep patterns are intrinsic, that is they are a part of a young person’s physiological and psychological development at a time when it is clearly documented that the changes of puberty are beginning at an earlier age. As teens grow, the intrinsic or biological clock changes causing them to be inclined to fall asleep later and wake up later. Because sleep is a biological need, this change in circadian rhythm placed against the demands of school schedule and increasing social experiences, teens may become sleep deprived. Missing one hour of sleep nightly for six nights in a row has the same effect as pulling an “all-nighter.”

Teens have little control over their bodies’ physical needs, but may be able to make sleep-healthy choices in the following areas of their lives:

• Erratic or consistent sleep schedules
• Cycles of stimulant usage
• Taking risks and experimenting
• Responding to academic pressures
• Managing increased social obligations
• Looking at job opportunities and desire to work
• Managing family stress
• Participation in recreational interests and extra-curricular practice requirements.
• Responding to societal expectations for greater cognitive maturity and making complex choices
• Thinking about the societal view of sleep as a luxury rather than necessary function

(Carskadon, 2000; Graham, 2000; Wahlstrom et al., 1997; Wilkoff, 2000)

Additional environmental influences on sleep patterns include: viewing TV violence; computer, phone, video games; as well as a lack of time to unwind and develop a relaxing routine. “Family stresses such as loss, illness, hospitalization, relocation and emotional turmoil within the family are additional influences because “increased stress and anxiety associated with sleep loss are likely to activate an alarm response.” (Preteen Children…, 2002)

4. What are some common consequences of insufficient sleep?

Sleep is necessary for learning and is “most important during periods of brain maturation” such as adolescence. (Dahl, 1999) Sleep is “food for the brain…. Inadequate sleep affects many segments of our society, but adolescents appear to be particularly vulnerable and face difficult challenges for obtaining sufficient sleep.” (Wahlstrom, 1999) “Adolescents must develop more self-control over behaviors and emotions that involve the prefrontal cortex, one of the last areas of the brain to develop. The onset of puberty has declined, creating enormous vulnerability as young people face the cognitive and emotional challenges of earlier development with relatively less cognitive maturity, but now with lots of personal freedom, complex choices and relatively few constraints.” (Graham, 2000)

What happens to an adolescent when the amount of sleep is inadequate? Even though the research in this area is largely anecdotal, there are a growing number of controlled studies that are supporting the data from young persons, their teachers and their families.

Adolescents seem to be particularly vulnerable and face difficult challenges when faced with sleep deprivation. Some of the known consequences of insufficient sleep are:

• Memory lapses
• Attentional deficits
• Poor performance at school
• Depressed moods or decreased ability to control emotional response
• Slowed reaction time or “micro sleeps”
• Increased likelihood of stimulant use (caffeine, nicotine)
• Difficulty with divergent, creative or strategic thinking
• Sleepiness and difficulty getting up for school on time
• Behavior difficulties
• Difficulties with task completion
• Impulsivity, difficulty sitting still

(Carskadon & Roth, 2000; Dahl, 1999; Graham, 2000; Wahlstrom, 1999; Wahlstrom et al., 1997)

One interesting study showed that students were able to perform one complex or difficult task (a computer task, for example) even when sleep deprived, but performance was significantly diminished if the student was required to perform two complex tasks (a difficult computer problem handling simultaneously a social situation). Thus during adolescence when a primary developmental task, such as gaining control over one’s feelings, is coupled with increasing intellectual tasks, gaining skill in cognitive areas—sleep deprivation significantly reduces performance. (Graham, 2000)

A lapse of attention or a “micro sleep” during a high school class may result only in a poorer grade or in reduced interest in a particular subject. But a micro sleep behind the wheel of an automobile may well have tragic consequences: young drivers (age 25 and under) are responsible for more than ½ of the 100,000 drowsy driving crashes each year—which injure 71,000 and kill 1,500. Other injuries at work or at home may also be the result of sleepiness. (Carskadon & Roth, 2000; Dahl, 1999; Graham, 2000)

Finally, while adolescence is a time of great emotional and behavioral turmoil, these “difficulties are currently the largest source of morbidity and mortality among adolescents.” (Dahl, 1999) Even if sleep deprivation plays only a small role in these situations, we know that young persons are particularly vulnerable both to these areas of complex growth and to the need for sleep. “Children need a safe and secure base and get it at home or school. If neither provides it, potential for trouble exists.” (Graham, 2000)

More research is needed to clarify the relationships among these factors, but in the meantime, helping adolescents be well rested on a regular basis may well support them in these transitional years of “seeding the values and habits that will shape their lives.” (Carskadon & Roth 2000)

5. What is the relationship between adolescent sleepand school start time?

In addition to considering a different start time for high schools, there are a numerous ways in which schools may be “sleep friendly:”

• School staffs can learn more about adolescent sleep needs and patterns.
• Teachers can become more aware of sleep or alertness difficulties.
• Information about sleep can be incorporated into health, biology, or psychology curricula.
• Class responsibilities and extra-curricular schedules and requirements can be restructured to accommodate adolescents’ sleep needs.
• Schools can work with families so that good, regular sleep habits can be established.
  
  

(Carskadon & Roth, 2000)

Considerable research has been done, primarily in Minnesota, on the consequences of a later start-time for high schools and on the community- and school-based initiatives that led up to these changes. There are a few strong recommendations that permeate this research, which was done in both urban and suburban schools, although many of the researchers describe their findings as still preliminary.

One recommendation found throughout the literature is that changing the start time for high school students has far-reaching effects throughout the community thus necessitating a school district’s taking its time to involve all stakeholders in a deliberately paced process of research, discussion, and decision. Districts who inaugurated these changes successfully, started by asking some compelling questions: Are the data on adolescent sleep needs of sufficient merit (in both quality and relevance) to warrant our consideration? What gains to we hope to see by shifting the start-times? What might we lose in this process? What will it take—in terms of resources and process—to bring the schools’ schedules in line with what we know about adolescents’ sleep needs? (Wahlstrom, 1999)

A second finding from all the sources was that a change in school start time has a profound and far-reaching effect on family life—both in negative and positive ways. Some parents reported the positive results of their children having more time for breakfast and that the rising/getting-off-to-school routine went more smoothly. Other parents reported less significant change in the family patterns. (Wrobel, 1999)

Thirdly, there was universal agreement that there are too many demands on the time of adolescents, and that no matter how school schedules are structured and re-structured; there are still only 24 hours in a day. (Quoting Mahowald in “Teens have….,” 2002)

Another finding, common across all the communities studied, was that adolescents held a perception that success both as adults and as high school students resulted from overextending themselves in their work and in their high school activities. Clear norms with regard to time were strong influences on students and their families as they considered and adapted to altered start-times for school. (Wrobel, 1999)

In some ways, however, the findings differed markedly between the urban and the suburban schools: In affluent communities, parents were able to accommodate the changed needs for transportation to school and activities. In less affluent schools, transportation resources were limited or non-existent and affected the level of participation in after-school activities. Urban participants noted concerns about less time for students to work after school—a concern not expressed by the suburban community. In fact, when 15 suburban employers were polled, fourteen of them indicated the later dismissal time had had no effect on their businesses.

A clear majority of the suburban teachers reported that they “liked the change,” but the urban teachers were more evenly split between liking and not liking (45.2% to 45.7%). Only about 1/3 of the teachers who reported that they did not like the change, however, included needs of students in their list of negative concerns. Urban teachers did express concerns about student safety at a later dismissal time, a concern not raised by suburban teachers. (Kubow et al., 1999)

Suburban teachers reported noticeable improvements in student behavior (quieter hallways, less misbehavior in the lunchroom), but urban teachers observed no general change in behavior. Schools in both settings reported better attendance and less tardiness.

Most of the teachers in the study reported that students are more alert during the first two periods of the school schedule, but there was considerable unhappiness about the “raggedness” of the last period of the day with students being dismissed early for athletic or other extra-curricular responsibilities. Some teachers also reported that students seemed more tired than before at the end of the day. Students, on the other hand, indicated that they were often enough more alert during the school day that they were able to get homework done during the class periods. (Carskadon & Roth, 2000; Wrobel, 1999)

Who then should be involved in these discussions about altering the start/end times for high school?

• Principals at all levels (elementary, middle and high school),
• School staffs and families (since these changes affect both personal and family schedules),
• Extra-curricular leadership (especially coaches and others involved in league athletics).
• Interested parents of students at all levels
  Wahlstrom, 1999; Wrobel, 1999)

In communities where stakeholders were involved in the process of inquiry and decision-making and who felt the process was open and responsive were better able to understand how the schools’ new schedules could meet their needs.

There is still considerable research to be done on the effects of the later start time on student learning, and there is no evidence that a later start immediately, directly improves student achievement. Still, “the research on adolescent sleep patterns is indicating that some change in school starting times may be beneficial.” (Kubow et al., 1999)

References for
Literature Review
for Sleep Needs for Learners Committee
August 30, 2002

Adolescent sleep and school start times. (n.d.). Sleep News and Research. Available August 30, 2002, from http://talkaboutsleep.com

Are you a zombie in the morning? (n.d.). Talk about sleep. Available August 30, 2002, from http://talkaboutsleep.com

Back to School? Help your child get a good night’s sleep. (n.d.). Talk about sleep. Available August 30, 2002, from Sleep News and Research Web site: http://talkaboutsleep.com

Carskadon, M., Ph.D., & Roth, T., Ph.D. (2000). Adolescent Sleep Needs and Patterns. Washington, D.C.: National Sleep Foundation.

Helpful article which summarizes research on adolescent sleep and includes a lengthy list of resources: agencies and electronic sources.

Carskadon, M. A. (1999, January). When Worlds Collide: adolescent need for sleep versus societal demands. Phi Delta Kappan, 348-353.

Carskadon writes widely on the topic of adolescent sleep. In this article, she presents a very readable description of some of the biological aspects of sleep and learning.

Carskadon, M. A., Ph.D. (n.d.). Work, School, Sleep & Circadian Timing in Adolescents. Contemporary Perspectives on Adolescent Sleep. Retrieved August 30, 2002, from http://www.websciences.org/adolescentsleep/carskadon.htm

Center for Applied Research and Educational Improvement. School start time study: final report summary [Online] Available May, 2001 at http://education.umn.edu/CAREI/Reports/default.html

Dahl, Ronald E., M.D. (1999, January). The Consequences of Insufficient Sleep for Adolescents: links between sleep and emotional regulation. Phi Delta Kappan, 354-359.

The author is an associate professor of psychiatry and pediatrics at the University of Pittsburgh Medical Center. He presents an understandable description of the societal and biological forces that shape the sleep/arousal balance and begins to discuss some of the benefits of providing some structures for adolescents that help them value adequate sleep.

Dozing off in class? Poll shows U.S. children complain of daytime sleepiness, fall asleep at school. (n.d.). National Sleep Foundation. Retrieved August 30, 2002, from http://www.sleepfoundation.org/pressarchives/children.html

Graham, M. G., Ed. (2000). Sleep Needs, Patterns, and Difficulties of Adolescents. In Sleep Needs, Patterns, and Difficulties of Adolescents. Washington, D.C.: National Academy Press.

Summary of a workshop presented at the Forum on Adolescence. Agencies involved were: Board on Children, Youth, and Families; Commission on Behavioral and Social Sciences and Education; National Research Council; and Institute of Medicine.

Hellmich, N. (2000, March 26). A teen thing: Losing Sleep. USA Today, p. 1.

Kubow, P. K., Wahlstrom, K. L., & Bemis, A. E. (1999, January). Starting Time and School Life: reflections from educators and students. Phi Delta Kappan, 366-371.

Authors discuss the findings from a survey of teachers and from focus group meetings attended by a variety of stakeholders. The efforts were to assess the impact of changing school starting times and to identify the areas of greatest concern.

Link found between kids sleep and attention problems. (n.d.). Talk about sleep. Retrieved August 30, 2002, from http://talkaboutsleep.com

Martin, D. (1999, August 1). Late to bed, early to rise makes a teen-ager...tired. New York Times, pp. 4,25-27.

Preteen children may not be getting enough sleep. (n.d.). Talk about sleep. Available August 30, 2002, from http://talkaboutsleep.com

The role of sleep in health and cognition. (2001, March 26). Talk about sleep. Available March 30, 2001, from http://talkaboutsleep.com

Sleep-deprivation among teenagers may impact academic and behavioral performance. (n.d.). Talk about sleep. Retrieved August 30, 2002, from American Academy of Neurology Web site: http://talkaboutsleep.com

Study shows importance of sleep to memory consolidation and task performance. (n.d.). Talk about sleep. Available August 30, 2002, from Sleep News and Research Reports Web site: http://talkaboutsleep.com

Teens have different sleep needs. (n.d.). Talk about sleep. Available August 30, 2002, from Dana Alliance for Brain Initiatives Web site: http://talkaboutsleep.com

Wahlmstrom, K., Ph.D. (n.d.). Accommodating the sleep patterns of adolescents within current educational structures: an uncharted path. In Contemporary Perspectives on Adolescent Sleep. Retrieved August 30, 2002, from http://www.websciences.org/adolescentsleep/wahlstrom.htm

Wahlstrom, K. L. (1999, January). The Prickly Politics of School Starting Times. Phi Delta Kappan, 345-347.
This article, written by one of the more prominent researchers and authors in the field of adolescent sleep, explores the need to involve all stakeholders in any planning for altered start times for schools.

Wahlstrom, K. L., Ph.D. (n.d.). Executive Summary - August 2001. In CAREI Home. Available August 30, 2002, from Center for Applied Research and Educational Improvement, University of Minnesota Web site: http://education.umn.edu
This is the summary of the school start time study at the University of Minnesota.

Wahlstrom, K. L., Ph.D. (1997, September). School Start Time: Technical Report II (Report No. II). College of Education and Human Development, University of Minnesota: Center for Applied Research and Educational Development.
Analysis of student survey data.

Wahlstrom, K. L., Ph.D. (1998, November). Minneapolis School District Start Time Study: Report of Findings. Paper presented at Center for Applied Research and Educational Improvement, College of Education and Human Development, University of Minnesota.

Wahlstrom, K. L., Ph.D., Freeman, C. J., Ph.D., & Heymans, M. (1997, January). School Start Time Study, Final Report Summary. College of Education and Human Development, University of Minnesota: Center for Applied Research and Educational Improvement.
Summary of findings of a study which considers the issues and impact of changing the starting times of schools. Includes some of the research findings concerned with sleep needs of adolescents and the dynamics of orchestrating a major school change.

Wilkoff, W., M.D. (2000, November). Getting serious about sleep. Good Housekeeping, 85.
Article describes how parents can tell if a child needs more rest.

Wrobel, G. D. (1999, January). The Impact of School Starting Time on Family Life. Phi Delta Kappan, 360-364.
This article outlines the significant impact on families of changing the school start time. He suggests some guidelines that may help school district policy makes make such changes in such a way that families’ routines are considered.