Teenagers Sleep and Learning

The role of the hippocampus as memory storer is now being more properly understood in relation to the learning process.

Until recently, it was thought that the part of the brain which stored memories was the hippocampus, and while this is true generally, its more specific role of housekeeper is now being examined.

What this means is this: the hippocampus’s role is not just to store memories – but it plays a huge role in organising those memories. The analogy of a housekeeper might aid understanding here.

Imagine the hippocampus as being a housewife/ maid. Every night, during REM sleep, the housekeeper comes along to sweep up the mess created by the day’s thoughts, to tidy up memories by placing them where they belong; to clear up unnecessary memories (is seeing a bit of gum on the ground a memory that is
important to your survival and emotional wellbeing? If not, then you don’t need to keep it); to make subconscious sense of conscious experiences. The hippocampus determines what is stored as long-term memory.

This memory “tidying up” process occurs during REM sleep.

It is now understood that teenagers between the ages of 13 to 20 need between 9 and 10 hours sleep a day, in order for the brain to develop properly, and for the hippocampus to have time to consolidate and “tidy” memories.

If the teenager only gets 5 hours’ sleep and does not get into the REM phase of sleep, his/her brain is not able to lay down the memories correctly / not able to sort out the day’s experiences.

The result is this: the student learns something on the Monday, gets 5/6 hours sleep, is not able to give brain time to consolidate the memory of what is learned, and thus, the next day, when asked to recall what was learned, the student finds it far, far harder to do so.

The danger of this is that it leads to the student thinking that he/she is somehow stupid or slower or less capable than those whose recall is better.

In other words, the student will develop a mindset that makes him/her believe that he/she is somehow not bright enough to retain and recall information - when in fact he/she is more than capable, it’s just his/her sleeping patterns that are making it harder.

Furthermore, it is now understood that teenagers who do not get their full quota of ten hours sleep a night build up a sleep deficit known as Sleep Debt.

Put simply, this means that teenagers who, say, sleep on average for only 6 hours a night, build up a four-hour sleep debt. So, each day, they owe their bodies an extra 4 hours sleep. This builds up over time which means that some students may end up owing their bodies over a year’s worth of sleep. That means that they have lost out on a year’s worth of brain growth and necessary development.

Also, there is strong evidence to suggest that students are not aligned to their internal body clocks. Most people have a natural rhythm for falling asleep and waking up. During a 24 hour day, we each have a specific time when our bodies
prepare for sleep and for waking. What scientists are now discovering is the importance of keeping this natural cycle regular.

So, if a student goes to bed at ten at night and wakes at six the next morning each day during the week (and gets his/her body used to that cycle), but disrupts that cycle by staying up later than usual on a Friday night, or sleeping in on the Saturday morning, then that student will have disrupted their natural sleep cycle. Even going to bed or waking an hour later than usual is enough to throw the natural sleep cycle out of synch. What this means is that they often are unable to get up at the usual time the following Monday and start the week afresh because they have disrupted their sleep cycle and often go to school while their subconscious mind is still busy with the process of tidying up the brain.

So they arrive at school, sleepy, and find it hard to concentrate in class. This is because the brain is trying to sort out the previous day’s memories while fresh data is being thrown at them to process. Many students then feel that they are somehow not very intelligent because they find it hard to concentrate during lessons.

Also, any disruption to the natural sleep cycle will make it harder to remember things and may even cause them to forget stuff that they had learned earlier.

Therefore, is important for students to fully understand the role of sleep in their lives and how important it is for the development of memory and self-belief.

One way that they can do this is by simply keeping a record of their sleeping habits over a period of about two to three weeks. This way, they will be able to determine their own sleeping patterns and can identify areas for improvement.

Maintaining a regular sleep pattern and getting the full quota of daily sleep, the brain is more able to process, understand, store and retrieve information.

If students disrupt their natural cycle before exams, they will forget information which they are revising. As much as 30% of information learned on a day can be lost if the student disrupts their natural cycle a day or two later.

This kind of reflection, therefore, is crucial for those students preparing for exams and should be encouraged both at home and at schools. Getting teenagers, however, to actually want to change their sleeping habits is another story altogether.