Written by György Buzsáki
A NEW UNDERSTANDING
Review by Gunnel Minett
Throughout human history we have been trying to understand how the brain works and in particular how it forms consciousness and the psyche. There have been many speculations and theories, all with one thing in common – they have looked at the brain from the outside-in. For a period this approach was taken to an extreme. Behaviourism tried to ignore any interpretation as to how the brain worked.
To this day, mainstream psychiatry, in particular in the United States, has a mechanistic approach, with its roots in Behaviourism. The Diagnostic and Statistical Manual of Mental Disorders (DSM-5) is a professional handbook, often used to diagnose patients and to draw boundaries among mental disorders. According to the American Psychiatric Association, the “goal in developing DSM-5 is an evidence-based manual that is useful to clinicians in helping them accurately diagnose mental disorders.” Some examples are; adjustment disorder, reactive attachment disorder, disruptive mood dysregulation disorder, intermittent explosive disorder, and somatic symptom disorder. This whole approach comes from the long tradition of an outside-in approach to understanding how the human brain works.
But, as the title of his new book The Brain from the Inside out, the Biggs Professor of Neuroscience at New York University School of Medicine, György Buzsáki argues that this is based on an outdated understanding of how the brain actually works. Instead, he says, we should distinguish between what is meaningful to a scientist who is observing the brain, i.e. the ‘outside-in’ perspective, and what you can be described as meaningful to the brain itself, i.e. the ‘inside-out’ perspective. In the outside-in approach, the brain is a passive receiver and interpreter of the outside world. But once you start looking at what actually happens in the brain, things start to look very different.
Drawing from a vast area of neuroscience research, Buzsáki argues that the inside-out approach is the way forward. Neuroscientists are presenting more and more detailed knowledge as to how our sight, hearing, touch, and physical movements are mapped to activities in different areas in the brain. Scientists, in turn, relate neural activity to external stimuli. He points to the fact that there is much more happening ‘on the inside’. This can only be fully understood by taking the inside-out approach. One example is how the brain handles space and time. It is not a coincidence that we use phrases such as ‘length of time’, ‘timeline’, ‘ the past is behind us’ and ‘the future is in front of us’. Time in itself is a ‘man-made’ concept that the brain has to interpret. So in order for the brain to perceive time it links space and time together.
Another example is how we use technology to externalise thought. The prefrontal cortical areas can be described as an internalised action system. Plans and thoughts are a form of internalised neuronal patterns that serve as a buffer for action, even if the action is delayed by days or even years. The same brain areas are also responsible for externalising our thoughts in the forms of; artefacts, language, art, and literature.
This has led Buzsáki to take the inside-out approach, which means that the brain is an active explorer of the world rather than a passive interpreter. Scientists should, therefore, aim to understand brain activity – its patterns and principles – without immediate reference to the outside world. “The brain,” he says, “should be treated as an independent variable because behaviour and cognition depend on brain activity, not the other way around.”
The brain is far from a ‘blank slate’ at birth. Rather, we are born with a set of ‘expectations’ that the brain actively tries to detect when we interact with the world around us. So the brain is more of an explorer than a passive processor of input from the outside world. The way we perceive the world may actively also be shaping how we engage with it. This means that it is the active exploration of environment that provides meaning to the neural information being processed. In other words, a far more active interaction than previously thought.
Another conclusion, Buzsáki draws, is that the brain can be described as two brains rather than one. This is similar to the thinking of Israeli psychologist Daniel Kahneman, who proposed ‘system one’ and and ‘system two’, in his book Thinking Fast and Slow. Buzsáki also refers to this in his book, and even confesses that he was rather concerned suspecting that he had been influenced by Kahneman, even though he had not read the book.
The early part of the book sets out the foundation of his argument. To illustrate why it is paradigm-shifting he presents a comprehensive review of much of ‘Systems Neuroscience’. The middle section focuses on brain rhythms, the hippocampal place cell system, as well as the logic and mechanisms of gain control in neural network operation. The final section, presents new ideas on the log-normal distributions found in neuronal organisation and how this supports the theories of fast and slow dynamics in the brain.
Overall, the book is profound and full of wisdom for both science and culture in general. It challenges the established views as to how the brain and the world work together, and it inspires new ideas regarding the psyche and consciousness. Despite detailed and sometimes technical explanations the book is accessible without too much previous knowledge. Scores of diagrams highlight the various experiments and concepts supporting this new theory.
We still do not know exactly how the brain works and we probably have a long way to go. But for anyone who wants to get a picture of how far science has reached, this book certainly offers that.
Oxford University Press 2019, ISBN-10 : 0190905387