In focus: 'The Teenage Brain' by Jeremy Jones
Please find Jeremy’s next fascinating instalment about the teenage brain below. This week, he is focusing on sleep.
Sleep
Sleep really is a strange thing. Why is it that we effectively spend a third of our lives unconscious, vulnerable and nearly totally unaware of our surroundings? A person living to 80 years of age will literally spend the best part of 25 years in this state of limbo. If we don’t get enough, then we suffer more from heart disease, depression, colds, strokes and even some forms of cancer. Neuroscience at least gives us some answers.
The thing about sleep is that it happens in 2 main cycles; first there is NREM sleep (deep, without dreaming with the body capable of movement); then REM sleep (‘dream sleep’ where because you are dreaming your body is paralyzed, a good thing for those of us that have vivid dreams). NREM sleep appears to be involved in synaptic pruning, an essential way of getting rid of those memory connections that you no longer need (what you wore on any given day or indeed most of what happened in that TV programme you watched 2 days ago). REM sleep is ‘dream sleep’ because it is when memories are consolidated and memory pathways are strengthened. As you can imagine, sleep is essential as it gives the brain time to form healthy memories and get rid of unnecessary memories. If you are interested, it is the GLIAL cells in the brain that perform these essential functions.
The other thing to remember is that Neurons are living cells. They respire all day, keeping you alive and just like all biological cells they produce waste products (imagine running a great distance; at some point you will get tired muscle cells and will need to sit down and rest). Sleep is the only time that you rest your brain enough so that it can carry out the essential cleaning out of those potentially dangerous waste products. No wonder then we succumb to sleep so often and for so long. From a neuroscience point of view it is absolutely essential, and yes 8 hours a night really is the magic number! Try to get that amount every day if you can, for a healthy mind and healthy body.
Finally, to make ourselves sleepy, we all produce a hormone/neurotransmitter called melatonin. For most people, this reaches a peak at about 9:30pm to 10pm, which is why we want to go to bed at about 10:30pm. For some reason, in adolescents, the body produces melatonin an hour later, so teenagers get tired an hour or so later than adults. Of course it follows that they then wake up an hour later as well. Perhaps have some sympathy for the tired teenager in your early morning lesson; their brain/body clock is literally a little out of sync with yours….
Sleep is a wonderful and vital biological adaptation; please make sure that you get enough!
Jeremy Jones