A brain full of contradictions
Developmental psychologist Eveline Crone has written a book about the uneven growth of the adolescent brain. The book deals with the complex relationship between the learning, the emotional, the creative and the social brains of adolescents.
Was that first love really so special, or do you remember it mainly because it was the first time? It may well be that that first love really did make a disproportionate impression, is the opinion of developmental psychologist Eveline Crone from the Leiden Institute for Brain and Cognition. She hasn’t exactly put any love-struck adolescents into the scanner, but she knows from research with adults who are in love that particular emotional reward areas in the brain are activated by looking at a photo of the object of their affection. And hormonal effects cause these very reward areas to be extremely sensitive in adolescents, much more so than in adults, while the areas of the brain which are able to calm the butterflies are slower in developing.
According to official guidelines, you are an adolescent from the age of ten to fifteen. It is a period of physical maturing and the first phase of adolescence, which continues until the age of 22. Adolescence was for a long time one of the least understood developmental stages, but in the past ten years a great deal of research has been done into the development of the brains of young people, research which has generated a wealth of new and often unexpected information.
Crone set up the Brain & Development Lab in Leiden three years ago. She and her co-researchers regularly publish articles on the development of the brains of children and adolescents, in leading journals such as the Journal of Neuroscience. Now it was time for a book aimed at a broader public – because adolescents can do with a bit of understanding.
"What is going on with adolescents?" sighs Crone, along with many parents. They have enormous difficulty keeping to a simple plan, yet their brains are more than capable of coming up with possibilities for inventive internet applications and other technical feats. How is that possible? Why do they do such worrying things, and why does their mood alter so quickly?
This is mainly a result of the uneven development of the brain, as has been shown by fMRI research. This imbalance is not yet a feature in younger children. It may well be that their planning and control system is not so well developed, but their sensitivity to particular emotional stimuli is also not so highly developed. At the start of puberty, from around the age of ten, the system becomes unbalanced. Adolescent brains react very strongly to the idea of reward; anticipating the kick is enough to spur them to immediate action.
Crone guides the reader with professional competence through all the relevant areas of the brain which make us the thinking, feeling and social beings that we are. She gives a tour of the brain stem, the complex brain areas which are responsible for such complicated tasks as long-term planning, learning from your mistakes and processing new information and making abstract moral assessments. This is also the site of our still largely enigmatic "social brain", which allows us to see things from the viewpoint of another person. But she also shows us the different areas which are responsible for the emotions, such as the pleasure centre. She explains the experiments which have been conducted, and those which could be done to find out how all the areas of the brain interact in adolescents.
An adolescent may experience frequent swings between different emotions, but it is not a simple case of a discrepancy between the rational and emotional areas of the brain. Sometimes adolescents spend too long thinking about something, Crone writes. Adults do not need to think too long about the risks of swimming with sharks; they immediately sense that the experience might be less than pleasant. For adults, the same brain areas are activated which would also be activated in instances of real danger. But for adolescents this automatic sensory reaction of "sharks – no way" is not yet accessible. They spend too much time thinking about the details of it: "Swimming with sharks? It could be dangerous, but then it might also be fun…"
And there are many things that adolescents can do very well, Crone writes, probably better than ever. Due to an over-production of grey matter in certain areas of the brain, adolescents are often extremely creative. Later, these areas are pruned down in the interests of efficiency. As a result of this over-production, adolescents can follow all kinds of peripheral paths that adult brains, with their built-in censors, have long ago ruled out. The mirror neurons, too, which allow you to copy movement easily, are extremely sensitive in adolescence. Combined with a good dose of daring, this means that some adolescents are extremely good at sport.
Het puberende brein is not a manual on "how to handle my adolescent", and adolescents are not likely to take a great deal of notice of it. But that does not mean that knowledge about the adolescent brain is not useful and worthwhile. The new insights have already given rise to a completely new field of research: educational neuroscience. This field focuses on adapting the learning situation at school to suit the requirements of the adolescent. Most problem-solving functions in the brain mature between four and twelve years of age. But an adolescent still can’t keep to plans. Could this mean that all that independent planning pupils have to do at secondary school is counterproductive?
And Crone has some tips for parents. When dealing with your adolescent, don’t emphasise all the possible risks and dangers of something he or she wants to do; you will be wasting your breath. Riding a moped under the age of 16 is quite simply forbidden because it is dangerous. End of story. You can be the one to spend sleepless nights worrying about that fractured skull.
(Source: Leiden University: October 2008)