Saturday, January 20, 2007

Why teens sleep longer

Parents often attribute their teenage son or daughter’s early morning grouchiness to the fact that they have not gotten a good night’s sleep thanks to all those long telephone chats, or watching television. However they might soon have to change that opinion, for a leading body clock expert has found that teens are basically biologically programmed to want more sleep.

Prof Russell Foster, a "chronobiologist" at Oxford University, set out to find why, as soon as they hit that 13-year mark, kids could turn from being sweet and adorable to unpredictable, arrogant and moody.

Professor Foster claims that the reason why teens always want to sleep that extra hour or to is because their brains are a "work in progress" and needs extra sleep.

He cites work by Prof Till Roenneberg and colleagues at the Ludwig-Maximilians-Universitdt in Munich, which showed that sleep timing changes noticeably as people age.

By the time of puberty, bed times and wake times start getting later and later i.e. teens tend to fall asleep late, as well as get up late.

The study by Prof Till Roenneberg’s team also found that the tendency to get up later continues until about the age of 19.5 years in women and 20.9 years in men.

This means, that teens are basically biologically programmed to want to sleep just that little bit longer in the mornings.

"On the basis of this data, we know teens want to go to bed two hours later than 40 to 50-year-olds, and in 10 per cent there is a four hour delay," the Telegraph quoted Professor Foster, as saying.

Professor Foster added that parents need to understand that the teen years are crucial for the brain, for that is the time that it matures, and that MRI scans of adolescent brains conducted over the past decade also back up this theory.

"Among the most sleep deprived are teenagers and an increasing body of evidence from sleep researchers suggests that relatively minor changes in the way we time educational activities could have major benefits," said Professor Foster.

He added that studies by Professor Carskadon with colleagues at the University of Toronto have suggested that one way to greatly improve the alertness and mental abilities of teens is to have a later starting time for schools, so that their brains get the rest they need. — ANI