Why is it that many teenagers have the
energy to play computer games until late at night but can't find the
energy to get out of bed in time for school? According to a new report,
today's generation of children are in danger of getting so little sleep
that they are putting their mental and physical health at risk.
Adults can easily survive on seven to eight hours' sleep a night,
whereas teenagers require nine or ten hours. According to medical
experts, one in five youngsters gets anything between two and five
hours' sleep a night less than their parents did at their age.
This raises serious questions about whether lack of sleep is affecting
children's ability to concentrate at school. The connection between
sleep deprivation and lapses in memory, impaired reaction time and poor
concentration is well established. Research has shown that losing as
little as half an hour's sleep a night can have profound effects on how
children perform the next day. A good night's sleep is also crucial for
teenagers because it is while they are asleep that they release a
hormone that is essential for their 'growth spurt' (the period during
teenage years when the body grows at a rapid rate). It's true that they
can to some extent catch up on sleep at weekends, but that won't help
them when they are dropping off to sleep in class on Friday afternoon.
So why aren't teenagers getting enough sleep? Some experts suggest the
presence of televisions, computers and mobile phones in children's
bedrooms may be to blame. Instead of reading a book at bedtime, children
are going to their rooms and playing computer games, surfing the web,
texting and messaging, or watching television. As these new childhood
pre-sleep activities have become more widespread, so more traditional
ones such as reading have declined. Dr Luci Wiggs, a researcher fellow
at Oxford University's Section of Child and Adolescent Psychiatry said,
'One of the problems whit these pre-sleep activities is that they are
unstructured, i.e. they do not have clearly defined start and end
times.' She went on, 'This is the first generation of children to face
such a plethora of alternatives to going to sleep and the long-term
consequenses in terms of physical and mental health for both the child
and their family can only be guessed at. What we do know is that
impaired sleep quality or quantity may compromise children's physical
health, academic achievements and mental health.'
Research has shown that teenagers have different sleep patterns from
younger children and adults. A timing mechanism in the brain regulates
our bodily functions over a 24-hour period. At night, the heart rate
falls, blood pressure is lowered and urine ceases to be produced. When
the sun rises, the body begins to wake up. One important change that
occurs at night time is increased levels of the 'darkness hormone'
melatonin, which helps us to fall asleep. Most adults start to produce
melatonin at about 10 p.m. When teenagers were studied in a sleep
laboratory, researchers discovered that they only began to produce the
hormone at 1 a.m. It is possible that this delay in melatonin production
is caused by the behaviour of teenagers. Playing with electronic
gadgets late at night stimulates the brain and exposes the teenagers to
bright lights which could cause the later release of melatonin. A more
likely explanation, however, is that the hormonal upheaval of puberty is
pushing the melatonin release back, in which case teenagers are being
kept awake by their bodies - they simply can't help their peculiar
sleeping behaviour. Although it isn't impossible for adolescents to go
to sleep before 11 p.m., or even to be alert in the morning, their
bodies make it difficult for them, and in some cases nearly impossible.
This is borne out by studies conducted in the USA, where some schools
have delayed the start of their classes to give their teenagers some
extra time in bed. Many teachers reported that students were more alert
and less moody. One school even noticed a significant improvement in the
educational performance of its students.
Issues surrounding sleep - who needs how much and when - are usually
given short shrift in efforts to improve student achievement. But modern
brain researchers say it is time that more schools woke up to the
biological facts and started lessons at a time better suited to their
teenage students.
