In Search of a Mechanism: From the Brain to the Mind - A Conversation with Chris Frith

Howard Burton

• Verlag: Ideas Roadshow
• Jahr: 2021
• ISBN:
  9781771701211
• Thema: Psychology
• Thema: Autism Spectrum Disorders

This book is based on an in-depth conversation between Howard Burton and Chris Frith, Emeritus Professor of Neuropsychology at University College London and Honorary Research Fellow at the Institute of Philosophy, School of Advanced Study, University of London. After an interesting exploration of how Chris Frith became interested in the study of schizophrenia, this detailed conversation examines topics such how our understanding of schizophrenia has evolved, the role of dopamine, how the brain works, the brain's predicting role, the phantom limb phenomenon, how the brain and mind link up, how culture affects the brain and much more.This carefully-edited book includes an introduction, Eyes on the Prize, and questions for discussion at the end of each chapter: I. Becoming a Psychologist - From "min and crys" to schizophreniaII. Probing Agency - Predictions, tickling and dopamineiii. The Active Brain - The principal actor in the theatre of experienceIV. Ideal Bayesian Operators - How our brains trump our mindsV. In Search of a Mechanism - How to connect the subpersonal with the personalVI. Humanistic Hubris - Dancing bees, stripping pine cones and The Royal SocietyVII. Free Will - And what it meansVIII. The Very Big Picture - Towards a grand unified theory of psychology?IX. Final Thoughts - Schizophrenia treatment and open questionsAbout Ideas Roadshow Conversations Series: Presented in an accessible, conversational format, Ideas Roadshow books not only explore frontline academic research featuring world-leading researchers but also reveal the inspirations and personal journeys behind the research.

Ideas Roadshow conversations present a wealth of candid insights from some of the world’s leading experts, generated through a focused yet informal setting. They are explicitly designed to give non-specialists a uniquely accessible window into frontline research and scholarship that wouldn’t otherwise be encountered through standard lectures and textbooks.

Over 100 Ideas Roadshow conversations have been held since our debut in 2012, covering a wide array of topics across the arts and sciences.

See www.ideas-on-film.com/ideasroadshow for a full listing.

Copyright ©2020 Open Agenda Publishing. All rights reserved.

ISBN: 978-1-77170-121-1

Edited with an introduction by Howard Burton.

All Ideas Roadshow Conversations use Canadian spelling.

Contents

A Note on the Text

Introduction

The Conversation

I. Becoming a Psychologist

II. Probing Agency

III. The Active Brain

IV. Ideal Bayesian Operators

V. In Search of a Mechanism

VI. Humanistic Hubris

VII. Free Will

VIII. The Very Big Picture

IX. Final Thoughts

Continuing the Conversation

A Note on the Text

The contents of this book are based upon a filmed conversation between Howard Burton and Chris Frith in London, England, on November 14, 2016.

Chris Frith is Emeritus Professor of Neuropsychology at UCL and Honorary Research Fellow at the Institute of Philosophy, School of Advanced Study, University of London.

Howard Burton is the creator and host of Ideas Roadshow and was Founding Executive Director of Perimeter Institute for Theoretical Physics.

Introduction

Eyes on the Prize

Chris Frith has long been fascinated by schizophrenia. As a young graduate student working with Hans Eysenck, he recalls how his interest was piqued even further by a serendipitous assignment as part of Eysenck’s internal review process for his second edition of his handbook of abnormal psychology.

“Students were handed out different chapters and I got the one on perception, which was mostly about schizophrenia. What particularly fascinated me then, and still does, is the problem of hallucinations and delusions.

“It’s easy enough to understand in principle if you’ve got affected regions of your brain why you become blind or deaf or can’t understand a concept or something, but it’s very difficult to understand why you start seeing things that aren’t there or believing things that are obviously not true.

“So, I was always interested in questions like, Can we think about a mechanism? and, How do we relate this to normal functioning? What is it that could go wrong in normal functioning that can make you start seeing things that aren’t there or hearing people talking about you, when they’re not?”

A key theme driving Chris’ entire research career is readily apparent from these early inquiries: using specific aspects of abnormal psychology—“what goes wrong”, if you will—as a natural window to help shed light on how, exactly, underlying “low-level” biological mechanisms are converted to “higher level” subjective experiences.

Meanwhile, a more detailed consideration of the mechanics of hallucinations initially drove him back in time, to the 19th century and his “big hero” Hermann von Helmholtz, who developed a deep insight on how we might objectively distinguish between external happenings in the world and internal happenings in our brains.

“Helmholtz pointed this out in relation to eye movements. When I move my eyes, obviously things jump about on my retina so there’s movement on the retina, but it’s due to me. And I have to be able to distinguish between movement on the retina due to me and movement on the retina due to something actually moving in the world.

“And he basically said that because there’s a message involved—you’re sending a message to your eye muscles to move the eye—you can use that signal as a way of determining what the corresponding movement is due to, whether it’s you or the world.

“So I took that up and thought, Maybe what goes wrong in schizophrenia is that this signal—this normal signal that tells you that it’s your movement or your action—doesn’t arrive for some reason.”

Well, what kind of a signal might that be? Combining his own experiments and analysis with a wealth of results from the broader cognitive science community, such as Wolfram Schultz’s pioneering work with monkeys, he eventually came to believe that the key signal in question was that of a prediction and reinforcement mechanism involving dopamine.

The brain, it turns out, is hardly the passive recorder of external happenings that scientists once believed, but is instead, vitally, a highly active participant, constantly predicting what will happen and regularly comparing its predictions with the incoming sensory input. Chris, together with colleagues such as Daniel Wolpert, began to focus intently on the importance of human agency, forthrightly calling himself “a motor chauvinist”.

“There used to be this view that everything was perception. They would draw a picture of the brain, and most of it would be the visual system. But we would say in contrast, ‘No, action is what the brain is all about. If you don’t have action, you’re going to die.”

Nowadays, most neuroscientists are not only convinced that this active prediction mechanism is an essential characteristic of the brain—quite possibly the essential characteristic—but after years of careful study, they have come to appreciate how it successfully harnesses all the nuances of advanced probability theory in order to predict and learn appropriately. The brain, goes the common description, is an “ideal Bayesian operator”, meaning that it is constantly invoking a deep understanding of Bayesian statistics as it engages the world around us.

Well, that’s hardly surprising. Since Bayesian statistics actually work, calling the brain an “ideal Bayesian operator” is really another way of saying that it uses statistics appropriately in its constant prediction-mechanism, which any evolutionary theorist would have very much expected in the first place. After all, it’s hard to see how a constantly predicting life form would last very long if the way it was going about making its predictions was all wrong.

But what’s deeply curious about this picture is that, while our brains are busily going about acting like ideal Bayesian operators, if you were to ask people to perform a basic statistical calculation, more often than not they would get it wrong. So somehow, there’s a big difference between what our brains are doing and what we, consciously, do.

And suddenly, we’re right back to Chris’ initial conundrum: how, exactly, are “lower-level” biological phenomena—such as those involved in our ideal Bayesian brains—related to “higher-level” subjective phenomena—such as becoming convinced that we should really buy that lott...