Dusk til yawn
There are three main types of sleep complaint: not being able to sleep (insomnia), sleeping too much (hypersomnia) and behaving oddly or having strange experiences related to sleep (parasomnias). While parasomnias, such as sleepwalking, are quite common in young people, you are more likely to come across the effects of insomnia and excessive sleepiness in the classroom.
Excessive daytime sleepiness can be due to breathing difficulties, often caused by enlarged tonsils or adenoids, or neurological disorders such as narcolepsy. But the main cause is lack of sleep.
Difficulty getting to sleep can be caused by what is called "poor sleep hygiene": worrying, discomfort, drinks containing caffeine near bedtime, irregular sleep habits or napping late in the day so that the child is not tired at bedtime.
Teenagers have a further important cause of difficulty in getting to sleep: a change in the body clock at puberty that shifts the time at which they are ready for sleep until later (the so-called "sleep phase delay"). A combination of this change and the habit of staying up late for social activities (or, perhaps, to study into the early hours) can easily result in shortage of sleep.
Not surprisingly, attempts to wake the teenager up in time for school or college may be met with resistance.
It is all too easy for parents to interpret this morning sluggishness (as well as sleeping in late at weekends in a vain attempt to make up "sleep debt") as typical adolescent behaviour. In fact, sleep phase delay and its behavioural consequences have a physiological basis that needs to be corrected by re-timing the sleep phase rather than simply remonstrating with the young person. (It is, of course, important to distinguish this state of affairs from other reasons why a teenager may not want to get up and go to school: school refusal, depression, chronic fatigue syndrome or substance abuse.)
Teenagers need to be aware of the significance of persistently having difficulty getting to sleep, of waking a lot in the night and having difficulty getting up in the morning. This is especially worrying if they are tired or falling asleep during the day, feel slowed-up, irritable or depressed and have mood swings, as well as difficulty concentrating, remembering things or making decisions properly.
Parents should suspect a problem if it is particularly difficult to rouse their child in the morning, if heshe falls asleep doing homework, needs caffeine drinks or sleeps very late at weekends. It is obviously significant if the teenager's behaviour is better after a good night's sleep or if the teacher has mentioned tiredness as a problem during the day.
And teachers? If there is a sudden fall-off in a pupil's academic performance or a change of behaviour - such as lack of concentration or withdrawal - or if a teenager keeps missing school or is persistently late, lack of sleep may well be the cause. You might be justified in enquiring about the pupil's sleep pattern - in particular how many hours he or she usually obtains.
Advice about sleep should be a part of health education, especially for adolescents, who should aim for at least nine hours' sleep a night. Good sleep hygiene means avoiding irregular sleep patterns, too much caffeine, exciting and prolonged activities at bedtime (in the form of TV or computer use, phone calls and texting), heavy meals or vigorous exercise in the late evening. Lying in bed awake for long periods sets up the unhelpful link between bed and being awake instead of being ready to sleep.
Sleeping in until very late at weekends confuses the body clock and maintains the abnormal sleep pattern on weekdays. An unhealthy diet, too little exercise, smoking and immoderate amounts of alcohol are also capable of disturbing sleep in their different ways.
Teenagers with a sleep problem should be encouraged to tell their parents so that the solution can be found jointly.
Gregory Stores is Emeritus Professor of Developmental Neuropsychiatry at the University of Oxford.
- Do you have sleep-deprived pupils in your class? Have your say in The TES online staffroom: www.tes.co.ukstaffroomhave+your+say
A BARRIER AGAINST LEARNING
The mother of a 15-year-old girl was taken to court by the local education authority and convicted because her daughter had failed to attend school consistently over the previous 12 months. The mother appealed against this conviction on the grounds that her daughter had something wrong with her sleep but the claim was treated with some scepticism.
I was called in as a sleep expert and discovered that, for the past three years, the girl had been going to bed progressively later because of reading, watching TV and doing homework in her bedroom until late at night. During these activities, she usually drank at least two mugs of coffee. Although she went to bed at about 10pm, she was unable to get to sleep until 2am or 3am. She then slept soundly but strongly resisted her mother's attempts to wake her, often going back to sleep and either not turning up at school at all or arriving late.
When at school, she was described as "looking awful" and "very morose" and she sometimes fell asleep in class. The standard of her work was much lower than it had been previously, when she was keen to succeed.
When I explained this to the court, the mother's conviction was quashed, and the girl was started on treatment aimed at retiming her sleep phase. She also stopped drinking coffee late in the day. Soon she was able to get to sleep at midnight at the latest and had much less difficulty getting up in the morning. From then on, her progress at school was good.