Richard E. Cytowic - Synesthesia

The MIT Press Essential Knowledge Series

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Richard E. Cytowic, M.D., M.F.A.

The MIT Press

Cambridge, Massachusetts

London, England

2018 Massachusetts Institute of Technology

All rights reserved. No part of this book may be reproduced in any form by any electronic or mechanical means (including photocopying, recording, or information storage and retrieval) without permission in writing from the publisher.

This book was set in Chaparral Pro by Toppan Best-set Premedia Limited. Printed and bound in the United States of America.

Library of Congress Cataloging-in-Publication Data

Names: Cytowic, Richard E.

Title: Synesthesia / Richard E. Cytowic, M.D.

Description: Cambridge, MA : MIT Press, [2018] | Series: The MIT Press essential knowledge series | Includes bibliographical references and index.

Identifiers: LCCN 2017038744 | ISBN 9780262535090 (pbk. : alk. paper)

eISBN 9780262346276

Subjects: LCSH: Synesthesia.

Classification: LCC RC394.S93 C963 2018 | DDC 152.1/89--dc23 LC record available at https://lccn.loc.gov/2017038744

ePub Version 1.0

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To Margaret

November 11, 1925August 25, 2017

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Synesthesia holds a cautionary lesson about blind acceptance of orthodoxy and the intellectual cost of groupthink. Science has its fashions as other fields do, times when everyone falls in step with prevailing dogma. But it also has turning points when conventional wisdom collapses and new paradigms take hold. This is what happened with the phenomenon of synesthesia.

The neurological trait of coupled perceptions that first appear in childhood is an enormously popular topic now. Yet a few decades ago, synesthesia was vehemently dismissed as bogus. The scientific establishment ridiculed individuals who claimed firsthand cross-sensory experiences as:

• crazy, attention-seeking, and prone to fantasy
• merely remembering childhood associations from coloring books or refrigerator magnets, which is why they imagined that A was red, or D was green
• engaging in metaphor that was no different than talking about warm or loud colors, sharp cheese, or bitter cold
• or else burned-out junkies suffering the residual effects of their assumed drug use.

In time, of course, attitudes changed. The new paradigm now dominates, and synesthesia is once again a subject of serious inquiry as it was at the turn of the previous century. Soon after I began studying it in the late 1970s, news of it spread through the popular press. Individuals would write or phone to say, You saved my life, or I didnt know there was a name for what I felt. I thought I was the only one in the world. Having endured a lifetime of being told that they were making it up, their astonishment and relief at being believed was a cathartic, even tearful, experience. And why shouldnt it be? Defending individuals from others ignorance helped them reassert their self-worth.

Synesthesia speaks to the essence of who one is. It celebrates the singularity of the subjective self. The emphasis on subjective, first-person experience matters because what critics always want is a third-person proof of it, a technical verification by some machine. I have always thought this sad because it betrays societys bias toward objectification. It devalues an individuals interior world and what is personally meaningful to them. Happily, one of the paradigm shifts wrought is that so-called objectivity is rather iffy. Not everyone sees the world the same because each brain individually filters and distills the universe in its own unique way. Point-of-view turns out to matter a lot in both science and everyday life.

Speaking about Wednesday Is Indigo Blue, Oliver Sacks said, Twenty years ago, synesthesiathe automatic conjoining of two or more senseswas regarded by scientists (if at all) as a rare curiosity. We now know that perhaps one person in twenty is synesthetic, and so we must regard it as an essential, and fascinating, part of the human experience. Indeed, it may well be the basis and inspiration for much of human imagination and metaphor.

The science of synesthesia now spans several levels of magnitudefrom DNA at the molecular level, to early cognition, brain imaging, all the way up to whole-organism behavior that includes art and creativity. Brain organization is now seen as multiplex rather than modular, a formulation popular in the 80s that insisted the senses traveled along isolated channels and could not interact.

We now know that the senses are highly intertwined and that the cerebrum is full of recurrent feedback and feedforward loops. Human sense receptors are formed and governed by evolution. They are fixed in the sense that they let us apprehend only a mere fraction of reality. We cant retune them to respond to frequencies other than those they already do, but we can appreciate that people with synesthesia are privy to the vast interconnections among the senses and a new texture of reality.

Washington, DC

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