Knowing One's Place: Space and the Brain - A Conversation with Jennifer Groh

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 ©2014, 2020 Open Agenda Publishing. All rights reserved.

ISBN: 978-1-77170-069-6

Edited with an introduction by Howard Burton.

All Ideas Roadshow Conversations use Canadian spelling.

Contents

A Note on the Text

Introduction

The Conversation

I. From Ticks to Brains

II. Historical Background

III. Frames of Reference

IV. Mysterious Overlap

V. Smell

VI. Brain Maps

VII. Ice Cream Cones and Multiplexing

VIII. Navigating Rats

IX. Neuroplasticity

X. Evolutionary Mechanisms?

XI. The Road Ahead

Continuing the Conversation

A Note on the Text

The contents of this book are based upon a filmed conversation between Howard Burton and Jennifer Groh in Durham, North Carolina, on October 30, 2014.

Jennifer Groh is Professor of Psychology and Neuroscience, Neurobiology and Computer Science at Duke University.

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

Introduction

Framing Evolution

Part of the problem of appreciating the full complexity of neuroscience is that even the complexity is, well, pretty darned complex, coming in all sorts of mesmerizing varieties.

There is the obvious, in your face, sort of complexity, based upon the sheer volume of possibilities: coming to terms with the vast number of neurons in the brain, grappling with how to go about isolating one specific protein out of thousands, and doggedly following each one down its own particular thousand-fold biochemical pathways.

But then there is a much more subtle sort of complexity, the sort that is not immediately obvious to a non-specialist but upon further reflection presents a vast number of seemingly insuperable obstacles to our understanding.

Take vision. Nothing could be more natural than blithely declaring that sight involves the brain appropriately processing the signals that it gets from our eyes. Which is true, of course, as far as it goes. But dig a little bit deeper and a much more sophisticated picture starts to emerge.

Duke neuroscientist Jennifer Groh has spent the vast majority of her research career doing just that: looking to unravel the subtle, and often overlooked, complexity of how our brains develop an understanding of where we are.

"The photoreceptors in our eyes give us a representation of where visual information is, where objects are in the world; and that frame of reference depends on where the stimuli are with respect to the array of photoreceptors. In other words, it depends on where the stimuli are with respect to your eyes.

"Well, we can move our eyes; and we do. In fact, we move them a lot—about three times per second—and we move them really fast, at a speed of about 500 degrees per second.

"That’s a lot of eye motion that the brain has to deal with, to compensate for. It has to assemble the snapshots that are taken by the photoreceptor array at each of the