Neuroscience and Child Psychotherapy

Five Neuroscience and child psychotherapy

Introduction

There have been many developments in our understanding of children's psychological and emotional development in recent decades, but no field has altered more dramatically and presented more challenges than that of neuroscience. In this chapter I will outline some of the main developments, in an uncomplicated way, and consider just what impact this new research might have both on our understanding of children's psyches and on how we might actually work clinically with children and adolescents. Of course neuroscience is by no means new to psychoanalysis. Freud himself, with his neurological training, showed enormous prescience in predicting the kind of developments that would not actually occur for another century: 'we must recollect that all our provisional ideas in psychology, will presumably some day be based on an organic superstructure'.

Innovations such as the MRI scan have opened up to scientific examination vast areas of brain functioning heretofore hidden from view. In the past our knowledge was gleaned only by cruder means such as autopsies on dead brains: if the brains of a dead person with a particular disorder showed a particular organic feature then scientists assumed that the symptom was due to organic causes, with no idea that experiences might affect the brain. Although neuroscience might still be in its infancy, our understanding is becoming more sophisticated, and it is now possible to observe, through scans, brain activity corresponding to very specific emotional states such as excitement or fear.

I will try to keep to the least technical and most clinically pertinent features of the research, taking in some fascinating facts about the human brain and its evolutionary history, about how experience affects both the architecture of the brain and its hormonal system, about the impact of trauma and neglect on the brain, in passing touching on mirror neurons and on some questions about memory and how emotional learning and remembering takes root. The chapter will also pay some attention to differences between right and left brain functioning, and - without any of us needing to be neuroscientists - I hope to convey a sense of the role of a few of the key parts of the brain that seem central to emotional functioning. Thinking about such matters can prod us to consider carefully what we prioritise in the therapeutic process and also raises questions about whether we should be hopeful or pessimistic about the possibility of change and growth after the first few years of life.

The brain: some facts and evolutionary history

Our brains are highly complicated and able to make incredibly complex calculations about psychological matters via almost infinite links and complex structures, within fractions of seconds. The fundamental units of the brain are 'neurons', which are long entities with a central nucleus (containing genes), and long extensions called axons.

Neurons connect to each other via synapses, which enable the transmission of neurotransmitters, which can then fire neuronal activity further 'downstream'. The average neuron incredibly connects directly to ten thousand other neurons and the average brain has one hundred billion neurons. Each neuron has one or more axons, which send messages to other neurons, and axons branch so that there are far more synapses than neurons. In fact Pinker refers to one hundred trillion synapses in the human brain. Each neuron has a cell body and tens of thousands of tiny branches (dendrites) which do the receiving via electro-chemical messages. A piece of brain the size of a grain of sand contains one hundred thousand neurons, two million axons and a billion synapses.

Furthermore different parts of our complex brains have evolved at different stages in our evolutionary history and serve different functions. Although slightly simplified, Maclean's concept of the triune brain is a useful starting point. This theory states that human brains can be related to three main stages in our evolutionary history: the reptilian brain, the limbic system and the neocortex.

Many aspects of our brain functioning have changed little since the reptilian brain reached its most advanced stage some two hundred fifty million years ago in reptiles, although it first evolved in fish five hundred million years ago. As well as controlling things like heart rate, breathing, temperature and balance, it contains structures such as the brain stem which controls ancient but vital survival instincts, the best known of course being 'fight, flight or freeze', physiological and psychological states we see all too often in traumatised children. Some one hundred million years later, with mammals, the limbic system came into existence, maybe the region that psychotherapists particularly interact with as it is really the seat of our emotional life, and concerns how we make judgements, learn whether an experience is likely to be pleasant or not, and how we form emotional memories. It also contains vital structures that I will return to later, such as the amygdala and the hippocampus. The 'new kid on the block' is the neocortex, a mere two or three million years old, and its most complex form is seen in humans with our two cerebral hemispheres, responsible for human thought, language, imagination and consciousness.

It might be that the cerebral cortex undertakes, albeit loosely, many of the 'higher' functions that Freud believed resided in the ego, and which he saw as more highly evolved. An exercise I quite often undertake with myself when working with patients is to ask whether it is the reptilian or