This is the 2007 version. Click here for the 2017 chapter 03 table of contents.

Age-Related Changes in Sleep

A persistent myth about sleep duration is that people need less and less sleep as they age. Observational studies show no drop-off in sleep required, as people age. The number of reported nighttime awakenings goes up dramatically with age, however. That is the only consistent difference in sleep patterns of old and young people. At all ages there are wide variations between individuals; for example, in a sample of 70 year olds, the average amount of sleep per night ranged from 5 hours to 12 hours.

How do sleep patterns of young and old differ? How long does it take the average teenager to fall asleep? How can young adults fall asleep in less than six minutes?

Research indicates that teenagers take an average of 15 minutes to fall asleep. Very rarely does a person take 30 minutes to fall asleep, even in the unfamiliar environment of a sleep laboratory. Yet over a quarter of 11-16 year olds think they take more than half an hour to get to sleep, four or more nights a week (Webb, 1981). Evidently they do not notice when sleep actually starts.

Thomas Roth, a psychologist at Henry Ford Hospital in Detroit, found that about 25% of healthy 18-to-35 year olds fell asleep in less than six minutes. The other 75% normally took longer. However, "if subjects who normally took longer than six minutes to fall asleep were deprived of one hour of sleep a night for five nights, they fell asleep in less than six minutes as well" (Adler, 1993). In other words, one week of moderate sleep deprivation—an hour a night, for a week—made everybody fall asleep very quickly.

What did Dement propose?

William Dement, the Stanford University sleep researcher who helped start the modern era of sleep research, believed that teens needed up to 10 hours of sleep per night. He argued that the early rising required by many high school schedules in America—with many classes starting shortly after 7 a.m.—created major problems. "It is not uncommon to look at a high school classroom in the morning and see one-third of the students with their heads on their desks," he points out. He suggested that school districts move the starting times to later in the morning, but at the few school districts where this has been proposed, the idea was rejected as too inconvenient or expensive ("Combating student torpor," 1998).

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Copyright © 2007-2011 Russ Dewey