Air Date: Week of January 7, 2005

Living on Earth’s Jenn Goodman reports that sleeping in is a biological necessity for adolescents.

Transcript

CURWOOD: Just ahead: Dog bites man – in the pocketbook. First, this Note on Emerging Science from Jenn Goodman.

[SCIENCE NOTE THEME]

GOODMAN: The notorious tendency of teenagers to hit the snooze button while sleeping away most of a morning is no cause for alarm. As it turns out, adolescents’ sleep habits are just part of their biology.

New research from the University of Munich shows that children continue to sleep more hours, later into the day, until around the age of 20. But, at this age the body’s internal biological clock undergoes an abrupt change, after which most people require less sleep as they get older.

Scientists pinpointed the age at which this change occurs by plotting the sleeping habits of 25,000 people between the ages of eight and 90. Then they calculated the mid-point of each person’s sleep — the time half-way between when the participants reported that they went to bed and when they woke up.

The data showed that men continue to sleep late until the age of 21, while the turning point for women is nineteen and a half years - which might explain the reason why women develop earlier than men. Scientists suggest that because the shift in sleeping habits after age 20 is so dramatic, it can be used as an official marker for the end of adolescence. That’s this week’s Note on Emerging Science. I’m Jenn Goodman.

CURWOOD: And you’re listening to Living on Earth.

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[MUSIC: Inverse Room "The Bomb in Buddha's Lap": Pieces for the Left Hand (Creot Records) 2005]