THE BLOG

Teenagers: Moody, Lazy and Pretty Amazing

18/08/2015 20:23 BST | Updated 18/08/2016 10:59 BST

I've been teaching teenagers for over a decade. Sure, they can be moody, unpredictable and even aggressive at times and they certainly drive you mad. That said they're still pretty amazing. I know you'll probably take some convincing of this, after all they sleep in until noon, stay up playing computer games into the wee small hours and never tidy their rooms - you don't need to remind me of this, my son is rapidly starting to display the classic signs of teenhood. To be fair to teenagers, however, there's an awful going on there and we're now beginning to understand why they behave the way they do, and most of it has to do with some pretty exciting things going on in their brains.

There was a time, not so long ago, when conventional wisdom decreed that brain development was pretty much complete by early childhood. In fact, we have known for some time that at birth practically all the 80billion or so neurons in the brain are already in place, the hard work is concerned with connecting these neurons so that they can communicate with each other (a process known as synaptogenesis). In early childhood (up until about the age of five) there are so many connections being made that many of the unused ones need to be eliminated later on through a second process called cognitive pruning.

In the past our understanding of brain development relied heavily on post-mortems, which of course meant that the brains being examined were inactive. Current research is driven by new technology and groups of neuroscientists armed with sophisticated scanners that can peer inside living brains while they are carrying out a number of different tasks. Researchers like Sarah-Jayne Blackmore and her team at UCL use Functional Magnetic Resonance Imaging (fMRI) specifically to scan the brains of teenagers and, as a result, have reached some very interesting conclusions.

The bottom line is that teenage brains are still developing and are in a rapid and highly complex state of flux. The process that was once thought to reach a conclusion in early childhood has restarted in an area of the brain known as the prefrontal cortex. This particular area of the brain is home to executive functions (functions such as the ability to anticipate the consequences of our own actions, the capacity to decide between good and bad actions and the ability to suppress socially unacceptable behaviour). The prefrontal cortex is also concerned with social cognition (the way in which we cooperate and communicate with others) as well as allowing us to modify our emotions so that they fit within socially acceptable norms. This development continues well into the teenage years and the pruning process is much slower than in earlier years, often continuing into the early twenties.

This continuing development is bound to have an impact on behaviour and this is most likely why teenagers are so susceptible to peer pressure and risk taking. It's not that teenagers engaging is risky behaviours think they're invincible - they are fully aware of risky behaviours like smoking and drinking, it's just that they are more influenced by the risk perceptions of other teenagers and less by those of adults. The ones with power, therefore, are the popular kids because they have more influence over your teen than you do. Teens also register a deeper drop in mood as a result of social exclusion, so falling out with their mates really does feel like the end of the world.

So what about the staying up late and sleeping in until lunchtime? When my own son was much younger he would be up and about well before I began to stir, but the creep is now beginning. Very gradually he is staying up later at night and sleeping in longer in the morning, which is at odds with my own sleep pattern. Changes in the brain appear to be impacting on biologically based behaviours like sleep. According to Russell Foster, professor of circadian neuroscience at the University of Oxford, the twenty-four hour biological cycle of teenagers is different to those of adults, meaning that they are more alert later in the day - so insisting that your teenager gets up at 7am would be akin to expecting you to get up at 5am. So compelling is the evidence that some UK schools have now implemented a 10am start time (and, no, going to bed earlier won't help).

When we take into account the neurological as well as biological changes taking place during the teenage years, it's a wonder our teens aren't more of a handful. In fact, the majority of teens appear to function perfectly well despite the turmoil in their brains.

For me, that makes teenagers pretty amazing.