top of page

What English Teachers Need to Know about Teenage Brains


A teacher helping a young person study

English and the Neuroscience Link


Some may say what on earth does neuroscience and the development of teenage brains have to do with teaching English. My response as someone who works with teenagers all the time is EVERYTHING.


Until the invention of MRI scanning we used to think that developmentally children were done and dusted once they were biological adults. Their bodies had finished developing and growing and that meant they were ready to be adults. Then we discovered that the brain was only just starting to develop in a second very active phase as puberty changes in the body were nearly finished.


Neuroscientific knowledge changes all the time so this article may well be out of date very soon, but I propose a working model so that we can understand the changes and then improve our communication with teenagers.


Brain Development in Early Life


It has been established that the brain develops from the bottom up. All the structures are formed when the baby is born but they are brought on line in a staged way. There is growth of the brain in the first three years of life but because our skulls are a finite volume any growth after that means parts that haven’t been used are removed to make more room. Another important principle is that when different connections of the brain start firing together, then the more that often that happens the more they become “hard wired.” This is of course the way habits are born. The brain retains its ability to remould and develop all our lives but during the first 25 years of life is a peak time to develop habits that stand us in good stead in the future.


Human beings are a species that is born with very little ability to do much more than suck, and some of us can’t even do that at birth. However, the part of the brain that brings information in for central processing (the spinal cord), and the part at the base of the skull that controls our internal organs, and produces cortisol and noradrenaline and adrenaline are all working well. In the next three years the ability to control the way we eat, walk, hear, see and talk come on line. We all know that the under 5’s have lots of emotion but they are usually raw, unrefined and hard for the child to control.


Brain Changes from Teen to Adulthood


The next step is to ready the brain for adult functions. Adults need to take responsibility for children, each other and the wider group of adults in the “pack”. The brain changes quite radically to prepare for this. The limbic system fires up much more than in childhood. This limbic region, tucked into the middle of the brain, is comprised of a number of parts that undertake memory processing in new ways, and refines emotion, especially the ability to look out for danger. In Daniel Siegel’s handy model this is the thumb lain across the palm. (Mindsight ).



The rest of the cortex is activated during late teens and early twenties. The pre-frontal cortex (the part behind the forehead) which is responsible for fine judgement, and impulse control is the last bit to come on line. In teenagers this is only activated about 20% of the time.


Teenagers 'Emotional' Brain


Functional MRI scanning has been a very useful tool to find out which parts of the brain respond when doing different tasks. When teenagers are looking at faces with different emotions being expressed their limbic system lights up: more specifically their amygdala (the danger warning system), in adults it is the pre-frontal cortex. In other words, teenagers think with their emotions. Often wires can get crossed and they may read anger when the emotion being expressed by the other person is anxiety. As an English teacher (or a parent) try not to reveal your anxiety in your face – you may get an angry reaction as the teenager will be responding to the anger that they are seeing.


In case you have forgotten, I would like to give you some idea of what it is to think with your emotions. Remember the last time you lost your keys and you were already late for work? How many times did you look in the same place?


You had flipped your lid.


Your pre-frontal cortex was no longer activated and you were thinking with your emotions in a panic. The same thing happens when we get anxious or angry. Teenagers, angry and anxious adults, all need to have that intense emotion validated and calmed before the cortex can get activated again.


Validate Emotions for Improved Learning


All teachers when working with adults or teenagers need to have the skills to validate and calm the emotions before the student can learn efficiently. Just as important is to calm the brain stem. This is the part firing off with adrenaline and noradrenaline when we are under stress and being made angry or anxious. When students are being stressed at home calming techniques are even more important to start the day at school with, in order to allow the cortex and memory systems to function better.


The techniques of mindfulness, yoga, class environments that calm not stimulate, are all the order of the day. It is understandable that teenagers are so keen to write about very emotive subjects when in fact they think with their emotions. The angst, especially for girls, is high.


The Brains Chemicals at Play


Many more things change in the brain. Oxytocin levels are high at birth, during breast feeding and in teenagers. Biologically oxytocin does many things, and one of its main functions is to increase bonding. It’s nice to think that this explains peer pressure but it is probably more to do with finding a mate and procreating!


Dopamine, another brain hormone, is also high in teenagers. This chemical is one that gives you an intense feeling of satisfaction when it is produced. The issue for teenagers is that the dopamine receptors are being rearranged so that there aren’t quite enough of them and if there is also competition with alcohol and cannabis they easily get filled. Some would say that this explains risk taking and certainly this is the time of life when many risks are being taken in terms of leaving home and finding a mate. The risk taking of driving fast or jumping off bridges when uncontrolled by an active pre-frontal cortex probably explains the sharp rise in deaths from unintentional injuries in this age group. This is worse for boys, partly because of testosterone rises, but also because puberty starts later in boys and puberty seems to be the trigger for the second wave in brain development and the activation of the pre frontal cortex, so that also happens later.


Add this to the fact that there seems to be less of the calming chemical GABA in teenagers and you can see that teenagers have a big task to handle their internal changes never mind the external demands of the changes in the way adults treat them and the expectations put on them. They grow in weight, height and sexual characteristics, and many more brain changes than I have described are happening – no wonder they are so tired all the time. It is also no wonder that they become more immersed in themselves and sometimes seem oblivious to the needs of others, apart from those they really care about, as they are dealing with so much internally.


Understanding Teen Communication and Time Lines


Communication Cognition also changes markedly during teenage times and of course earlier for some, as we know that for some people hormones can start changing as early as eight years old (girls earlier than boys).


Most two year-olds do not have any concept of time. To tell them you will see them tomorrow is meaningless as they do not understand. For them if you are not there right now in the immediate present it is as if you are gone forever. The ability to have a concept of time develops over the next few years but really doesn’t get conceptualised much beyond the next few days until teenage times. Someone in early puberty may well be able to conceptualise events and plans a few months ahead but not much further. This is very important in terms of communication, as to be sure that you have understanding it is wise not to move ahead of their current time concept if you want to avoid a blank look.


The second point to assist good communication is to assess where the teenager is on the continuum of concrete to abstract conceptual thinking. Again becoming too abstract in a way that is beyond the student’s stage of development brings on the blank look. If you are noticing those blank looks in the classroom it is helpful to do some “one on one” explanations at a more concrete level if you are going to help them to achieve. Unfortunately for adults, and our school system, young people do not all develop at the same pace and at the same time.


The third point that can be useful is to recognise that the connections between the different parts of the brain are being brought on line at different rates.


Thus the complexity of thinking that is supposed to characterise adult thinking is only just coming into play for teenagers. The outcome of this is to make sure that we take care not to overwhelm the circuits and don’t give too much information at once and not too many things to choose from.


It is important however to offer choice as that brings a feeling of control which is vitally important to brain development and it is also important to provide a sense of meaning for young people in helping them to understand what and why they are being asked to do.


Slowing Down Development


It is well known that the developing brain can be damaged, especially in the first few years of life, by any sort of abuse, whether it be physical, emotional, verbal, sexual or just neglect.


Teenagers’ brains can be and are damaged in a similar way. In addition teenagers have the influence of society with all the temptations of alcohol, cannabis and computer games which all have the potential to damage development and create addiction.


Mental illness commonly starts in this age group, with some estimates of 70-80% of mental illnesses starting before the age of 30 years. Anxiety and depression are the most common, and studies have shown 20% of teenagers in New Zealand High Schools with symptoms of depression.


Other factors that can slow development are poverty, especially when there is a big gap between the rich and the poor, parents with mental illness or alcohol and other drug problems, moving house and school frequently and having a disability, also all contribute.


Speeding up Development


Most teenagers do well. What helps? Certainly a stable home, with the absence of abuse, alcohol and other drugs helps. What the research from many studies has shown is that being accepted by a caring adult who gives you unconditional loving support, in a place where you belong is very important. Boundaries and consequences are important in addition to being respected for growing skills and autonomy.


The researchers in positive youth development talk about the importance of assisting young people to grow and develop competence and increasing skills for living which in turn leads to confidence. The ability to make connections emotionally as well as physically is very important as are developing values and meaning that build character. These moral values leading into caring which drives the young person to make a contribution all help to provide the milieu that assists development. Coping with stress is a final addition to the list of seven “C’s”. This last seems to be an important skill to learn as young people have to cope with the pressures of social media, overwhelming vast amounts of information and a society in which there is little stability and constant change.


Thus I hope you agree that understanding the ways in which the brain develops and changes for teenagers is helpful, and hopefully as we understand more, we can all work more effectively with our young people as we assist them in their journey through life.



Dr Sue Bagshaw qualified as a doctor in London and arrived in New Zealand with 3 children under 5, adding a true kiwi a few years later. She and a team of others set up a Youth One Stop Shop in 1995 which is still going today after a brief interlude through 2010/2012. This service provides physical, sexual, mental, social and spiritual health care to 10-25 year-olds free of charge. Sue is the Director of the Collaborative Trust which undertakes evaluation, research and training in youth health and development and she is also a Senior Lecturer in Adolescent health in the Department of Paediatrics of the Christchurch School of Medicine University of Otago.


This article has now twice been featured in the New Zealand Association for the Teaching of English Journal.







bottom of page