Neuroscientist Probes Myths About the Teenage Brain
Adults have often wondered what's going on in teenagers' heads but in Inventing Ourselves: The Secret Life of the Teenage Brain, cognitive neuroscientist Sarah-Jane Blakemore argues that understanding students' neurological development can help dispel negative myths about adolescent learning.
Blakemore, a cognitive neuroscience professor at University College London and the mom of two tween boys, dug into some of her findings this week, as the book was released in the United States. (The interview has been edited for clarity.)
We often think early childhood is this dramatic window of learning and development in the brain, and you're highlighting adolescence as a different kind of window. Can you talk a little bit about that?
I was told when I was an undergraduate that the human brain pretty much stopped developing after mid-childhood. From [magnetic resonance imaging] of living brains, we've discovered that that's not true at all—in fact, the brain continues to develop right throughout childhood and adolescence and even into the 20s. That has launched an entire research field investigating the links between brain and behavioral development and social development during adolescence.
What would you say is the most common myth about adolescence that you've been able to start breaking down as you've studied the neuroscience of it?
The adolescent-typical behaviors like risk-taking and impulsivity and self-consciousness, peer influence, and even the stereotype that adolescents are lazy—those kinds of behaviors were for a long time put down to the individual adolescent being difficult or making bad decisions or being lazy. But actually, we now understand these behaviors as a consequence of very natural and adaptive biological development.
Are there any differences in adolescents' approach to learning, compared to childhood or adulthood?
We did a study looking at learning of quite complicated reasoning skills. Contrary to the idea that [interest and learning] kind of goes downhill from childhood, we found exactly the opposite effect. For learning that relies on things like relational reasoning [the ability to recognize patterns in information] ... that ability was highest in late adolescence. So that suggests that there are some things we'd do better to wait to teach until later on. We didn't really know why, whether it's because the brain is developing then or whether it's because [older teenagers] become better at learning strategies.
What might teachers take away from a study like that?
It might be that for really complicated math, like algebra, it might be more efficient to wait until the brain and the learning strategies are developed enough to be able to grasp those concepts. But we didn't actually look at 'math,' but at that one skill.
How has working directly with teenagers changed your research?
We were designing an experiment and we wanted to know whether cognitive performance on academic tasks is changed if teenagers are being watched by their friends because obviously, this is quite a normal thing in everyday life. So we took the question to a group of teenagers in a school that we worked with in London. And they told us that they felt that the only condition that would really matter was if they thought their friends were actually evaluating that performance, so not just watching them perform.
So we took that up. We changed our paradigm asked the observing friends to monitor and to evaluate afterward. Teenagers' performance decreased on academic tasks when friends were evaluating them—and that is not the case for adults.
There's been a lot of discussion of how to look at risky behaviors by teenagers. Could you talk about what you've found?
There's no evidence that adolescents don't evaluate risk as well as adults. They absolutely understand the risk, but in the moment, ... social-risk avoidance and the avoidance of being excluded from the peer group is more important to teenagers than the avoidance of health risks or legal risks. That's not necessarily a good thing, but it's important for teenagers and it kind of puts risk-taking in a more rational light. I think it's a side effect of that developmental process. It's really important to take risks and to learn from trial and error. So there is probably a drive specifically to take risks in adolescence. We see it even in animals.
Could you talk a little bit about the mental health issues that tend to show up in adolescence?
Most mental health problems first appear in adolescence whether you're talking about depression or anxiety or addiction, eating disorders, schizophrenia. ... In fact, that's how I got interested in [adolescent neuroscience] because I was interested in, what is it about the teenage brain that makes teenagers vulnerable to mental illnesses. We don't really know the answer yet, but I think it is very, very complex and involves all sorts of changes that happen at around that time. Puberty changes the brain, which undergoes a huge kind of reorganization in early adolescence. You've got hormone changes that affect your mood and well-being ... directly, but also indirectly, because when children go through puberty, they go from looking like little children to suddenly seeming like adults--and that affects the way society treats them. Suddenly there's a lot more pressure.
And there are also social changes, like most children moving from a small primary school to a larger secondary school at around the age of 11. That that means that, you know, the whole kind of social world is just mixed up for a bit and it's a very confusing and unstable social hierarchy. So lots of different things are changing all at the same time, and I think together these things make adolescence a vulnerable period for mental illness.
If you could advise teachers and principals to do one thing that you think would improve how they interact with teenagers, what would it be?
Teachers are teaching young people like adults and sometimes have the tendency to put adult expectations on them, like expecting [young adolescents] to think about connecting subjects they are taking to their future careers. But actually, the parts of that brain that are involved in planning and decision-making and awareness are still very much in development. It's really useful to remember that teenagers make decisions that adults wouldn't make when it comes to thinking about their future.