The Teacher and the Teenage Brain

John Coleman

• Publisher: Routledge
• Year: 2021
• ISBN:
  9781000390537
• Edition: 1
• Topic: Education
• Subtopic: Education General

The Teacher and the Teenage Brain is essential reading for all teachers and students of education. This book offers a fascinating introduction to teenage brain development and shows how this knowledge has changed the way we understand young people. It provides a critical insight into strategies for improving relationships in the classroom and helping both adults and teenagers cope better with this stage of life.

Dr John Coleman shows how teachers and students can contribute to healthy brain development. The book includes information about memory and learning, as well as guidance on motivation and the management of stress. Underpinned by his extensive work with schools, Dr Coleman offers advice on key topics including the importance of sleep, the social brain, moodiness, risk and risk-taking and the role of hormones. This book is extensively illustrated with examples from classrooms and interviews with teachers. It explicitly links research and practice to create a comprehensive, accessible guide to new knowledge about teenage brain development and its importance for education.

Accompanied by a website providing resources for running workshops with teachers and parents, as well as an outline of a lesson plan for students, The Teacher and the Teenage Brain offers an innovative approach to the understanding of the teenage brain. This book represents an important contribution to teacher training and to the enhancement of learning in the classroom.

Chapter 1

Ten things every teacher needs to know about the teenage brain

This is a book for teachers, but what can teachers gain by learning about the teenage brain? How will this subject assist teachers in their work? In the process of writing this book, I have asked many teachers what it is about the teenage brain that they would like to know. I have had many different answers, but one teacher got to the heart of things by asking:

• “Can you tell me how to engage the reasoning side of a teen’s brain?”

This is a great question – a two-pronged question. At first, it appears to refer to logical thinking. It seems to concern the rational part of the brain. How can we improve the young person’s ability to solve problems, to reason, to engage in scientific thinking?

However, on second thoughts, there is something else here. The question could be asking about the awareness of consequences. How can we stop teenagers behaving thoughtlessly? The question raises the idea of a “reasoning side” of the brain as opposed to the emotional side of the brain. What does this mean? Where does it reside? How can we best facilitate it and support its development?

Other teachers asked a wide range of questions. Here are just a few.

• “Can knowing about the brain help me motivate my students?”
• “Is there such a thing as left-brain thinking?”
• “How to get through to an individual who is in a heightened emotional state?”
• “At what age does the fear factor kick in, so that they understand consequences?”
• “Is it really true that the brain shrinks during the teenage years? How can this be?”

There has been a lot of debate about whether neuroscience – the science behind brain development – can actually lead to more effective teaching and learning. My answer to this is a categorical YES! Knowing about the brain will not answer all teachers’ questions. It will not address everything you need to know about teaching. It may not necessarily help you with lesson planning, curriculum design or the use of technology in the classroom.

It will, however, make a profound difference to your teaching. The reason for this is that knowledge about the brain during the teenage years has altered the way we understand young people. It has given us new insight into their development during these critical years.

• Did you know that the teenage brain is especially responsive to rewards?
• Did you know that the brain matures from back to front?
• Did you know that the grey matter in the brain does actually reduce by about 17% during this stage?
• Did you know that memory processes are active during sleep, thus contributing to learning during the day?

If you are interested in these questions, and many others – read on. However, just before we get to my first of ten things – “A thing of wonder” – I want to outline the structure of this book. In this first chapter, I will describe ten ideas concerning the brain. This is a short introduction to some key concepts, many of which will be explored in greater detail later in the book. There will then be a chapter on other aspects of teenage development, and this will be followed by a description of my journey from thinking about the baby’s brain to considering the teenage brain.

Next will come a series of chapters detailing some major areas of research, including learning and memory, the social brain, sleep and so on. Finally, at the end of the book you will find three chapters with a more practical slant. Here I discuss the development of workshops and training on the teenage brain for teachers, students and parents. These chapters outline the background and activities that have made it possible for me to create these learning materials. More detail about the workshops can be found in Appendix 2 and the accompanying website (www.routledge.com/cw/coleman).

One last point. This book has been written during the pandemic of 2020–21. It is hard to know what the long-term impact will be on young people and on their lives in the future. I will refer to the pandemic in Chapters 2 and 8. At this stage we can only guess at how education, employment, health and social life will be impacted in the future. No matter how challenging and stressful the experiences of these years, young people will continue to change and develop. I know that the information in this book, describing the development of the brain during the teenage years, will remain relevant to teachers and to all who live and work with young people.

1. A thing of wonder

The human brain is a wonder and a mystery. It is a thing of magic, yet it is a concrete object. It is extraordinary – the most complex thing you can imagine. There is nothing in nature that has any parallel. Today, science is beginning to unravel a tiny fraction of the mystery, but only a tiny fraction.

To begin with the brain contains billions of cells, known as neurons. Your brain contains perhaps 80 or possibly 100 billion neurons. More than all the stars in the galaxy, more than the entire global population, more than the human brain can comprehend.

How is it possible to make sense of such an organism? It is of such complexity, yet weighs less than three pounds, and is something that you could easily hold in your hands.

All these billions of neurons are connected to other neurons in patterns and networks. We still understand very little about how these networks function, and how the multitudes and multitudes of neurons work together in systems to ensure that humans walk, talk, learn, memorise and collaborate together in social groups.

The brain operates by sending messages along pathways between neurons. Each neuron has branches that connect to other neurons. A neuron sends messages to other neurons by passing an electrical current, or impulse, along these branches. Remarkably, there is a tiny gap in the middle of each branch, known as the synapse. The message, the impulse, has to jump over this gap in order to reach the next neuron. There will be more about this in a minute.

I will now turn to the structure of the brain. During the teenage years, three areas are especially important. One is the prefrontal cortex, associated with thinking, reasoning, problem-solving and other intellectual activities. The second is the amygdala, an area buried deep in the brain and associated with emotion, sensation and reward-seeking. The third is the hippocampus, the area most associated with memory processes. These areas of the brain undergo major development and change at this time. You can see where these are located in Figure 1.1.

Figure 1.1 Simplified image of the structure of the brain, showing the pre-frontal cortex, the amygdala and the hippocampus.

The last 20 years have seen a giant leap forwards in our understanding of the human brain. This is because of the development of scanning technology. It is now possible to take pictures of the brain as it functions, without any great distress or discomfort. The technology is known as magnetic resonance imaging.

The development of brain imaging has provided amazing insights into the teenage brain. However, I have called this section “A thing of wonder” for a reason. Scanning can only tell us so much. Scanning allows us to see how much oxygen is going to different parts of the brain at any one time, which is a huge advance on what was possible 20 years ago. Nonetheless, this is still very limited. In the next sections, I will describe what we have learnt about the teenage brain. In the last section of the chapter, I will discuss what adults can do to assist with healthy brain development during the teenage years.

2. How the brain works

As I have said, the brain is enormously complex. While it is not necessary for a general reader to understand too much of the technical stuff, it is useful to have some basic knowledge about the brain and how it works. I will try and make this section as simple as possible.

I will start with neurons. Each neuron has branches that connect to other neurons. One branch is called the axon, while others are called dendrites. For each neuron, there is one axon, but many dendrites. A pulse, or signal, is sent out by the neuron, it travels along the axon, crosses the synapse and connects to a dendrite on the other side that takes it on to the next neuron. It is hard to comprehend, but this is happening millions of times in your brain during the course of any one second (Figure 1.2).

Figure 1.2 Image of a neuron, showing axon, dendrites and synapse.

The synapses play a central part in the story, as they can be seen as the on/off mechanism in the brain. Within the synapse are what are known as chemical messengers (or neurotransmitters). These are hormones that either help or hinder the transmission of neural messages. Synapses are designed to act as either facilitators or inhibitors of further travel of an impulse.

This is hugely important because there are simply too many stimuli entering the brain at any one time. The brain needs a filter mechanism. Without such a mechanism you would not be able to concentrate or pay attention, as you would be constantly distracted by other messages arriving in the brain. Some people like to say that the synapses are the air traffic control system for the brain, preventing constant mid-air collisions! (Figure 1.3).

Figure 1.3 Image of two types of receptor.

In addition, myelin is important. This is the substance that covers the axon, and it has two purposes. First, it helps speed up the transmission of a message. This is significant in adolescence, as the myelin around the axons increases in size during this stage, allowing faster transmission of signals from one part of the brain to another. Myelin also plays a big role in helping to keep the neurons, axons and dendrites separate from each other. You may be able to imagine what a tangle of connections there must be in such an extraordinarily small space in your brain. The myelin helps to keep things apart and function effectively.

It is now time to think about what makes the teenage years special as far as brain development is concerned.

3. What is special about the teenage years?

It is a remarkable fact that it is only in the last 20 years that we have learnt how much change occurs in the brain during the teenage years. Previously, it had been assumed that the brain had matured by the end of childhood. Now, as a result of studies using scanning technology, we understand that the teenage years are a period when the brain alters more than at any other time apart from the first three years of life.

This is important because a time of such change is a critical period. The experiences that a young person has at this stage will affect brain development to a greater extent than at other times in life. It is for this reason that the more teachers and other adults understand what is happening to the teenage brain, the better it is for healthy adolescent development.

This is the period when the brain goes through a major process of maturation. It becomes more efficient, and a variety of new skills and abilities develop. Memory, language, thinking and reasoning all improve. How does this happen?

I have already mentioned the change in the thickness of the myelin around the axon. This change allows impulses to travel around the brain in a faster and more efficient manner. In addition, all areas of the brain mature, and this applies especially to the three key areas of the brain I have already mentioned: the prefrontal cortex, the amygdala and the hippocampus. These areas do not necessarily mature at the same rate. As a general rule, it can be said that the brain matures from back to front, with the prefrontal cortex being the last to become fully mature.

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