Spikes: Exploring the Neural Code (Computational Neuroscience) [Paperback]

Fred Rieke (Author), David Warland (Author), Rob de de Ruyter van Steveninck (Author), William Bialek (Author)

Book Description

ISBN-10: 0262681080 | ISBN-13: 978-0262681087 | Publication Date: June 25, 1999

Our perception of the world is driven by input from the sensory nerves. This input arrives encoded as sequences of identical spikes. Much of neural computation involves processing these spike trains. What does it mean to say that a certain set of spikes is the right answer to a computational problem? In what sense does a spike train convey information about the sensory world? Spikes begins by providing precise formulations of these and related questions about the representation of sensory signals in neural spike trains. The answers to these questions are then pursued in experiments on sensory neurons.The authors invite the reader to play the role of a hypothetical observer inside the brain who makes decisions based on the incoming spike trains. Rather than asking how a neuron responds to a given stimulus, the authors ask how the brain could make inferences about an unknown stimulus from a given neural response. The flavor of some problems faced by the organism is captured by analyzing the way in which the observer can make a running reconstruction of the sensory stimulus as it evolves in time. These ideas are illustrated by examples from experiments on several biological systems.Intended for neurobiologists with an interest in mathematical analysis of neural data as well as the growing number of physicists and mathematicians interested in information processing by "real" nervous systems, Spikes provides a self-contained review of relevant concepts in information theory and statistical decision theory. A quantitative framework is used to pose precise questions about the structure of the neural code. These questions in turn influence both the design and analysis of experiments on sensory neurons.

Editorial Reviews

Review

"A joy to read.... This book will undoubtedly become a classic. Theideas presented in it have already begun (in no small part through thework of the authors) to reshape our views of the neural code. Thisbook will make them accessible to a much wider audience." Anthony Zador , Science

"Spikes is a really wonderful book. The particulartheory about how the brain works that informs the presentation, and thusdetermines how neural coding is to be described, is clearly thought throughand the arguments are attractively and intelligently presented." Charles F. Stevens, The Salk Institute

About the Author

Fred Rieke is Assistant Professor in the Department of Physiology and Biophysics, University of Washington. David Warland is Research Associate in the Department of Molecular and Cellular Biology, Harvard University. Rob de Ruyter van Steveninck is Research Scientist, William Bialek a Senior Research Scientist, both at the NEC Research Institute.

Product Details

• Paperback: 416 pages
• Publisher: A Bradford Book (June 25, 1999)
• Language: English
• ISBN-10: 0262681080
• ISBN-13: 978-0262681087
• Product Dimensions: 8.9 x 7 x 0.8 inches
• Shipping Weight: 1.4 pounds (View shipping rates and policies)
• Average Customer Review: 4.5 out of 5 stars  See all reviews (11 customer reviews)
• Amazon Best Sellers Rank: #105,306 in Books (See Top 100 in Books)

Customer Reviews

Most Helpful Customer Reviews

13 of 13 people found the following review helpful:

3.0 out of 5 stars Was provocative, but may not point the way forward., March 5, 2007

By 

Theo Theodopolous (USA) - See all my reviews

This review is from: Spikes: Exploring the Neural Code (Computational Neuroscience) (Paperback)

A decade ago, computational neuroscientists and some neurophysiologists were twittering with excitement about information theory. Finally, a tool that could decode the "noise" observed when we record neuronal spike signals!

These days...information theory has become part of the standard toolkit in a few types of experiments. But we're not much closer to understanding the neural code(s) than when this book was written. Nevertheless, Bialek's group of mostly physicists turned neuroscientists continue to develop information theoretic tools. Perhaps they'll come up with one that's not just another hammer.

The authors of Spikes may still turn out to have been ahead of their time (just like Barlow, MacKay and McCulloch, who originally applied information theory to neurons). Or their research program may turn out to have been a detour, a misguided attempt to find a particular physical universal in evolutionarily contingent biological systems.

If you're interested in theoretical neuroscience, I would definitely recommend Dayan and Abbott's textbook. van Hemmen and Sejnowski's "23 Problems in Systems Neuroscience" also has good bits. If you really want to read about information theory, David MacKay's new book is available on the web.

26 of 32 people found the following review helpful:

4.0 out of 5 stars Wow. Comes the revolution!, May 15, 2000

By A Customer

This review is from: Spikes: Exploring the Neural Code (Computational Neuroscience) (Paperback)

This book asks: How does a nerve convey information about the world toward the brain? It is a crucially important question - one of the most important questions in human history, in fact -- because before one can make realistic theories about how a brain works, one must know what sorts of signals it receives and acts upon.

We were all told, in basic biology, that this question was answered decisively in the 1920s: The nerve encodes and transmits information about the world in the form of frequency modulated pulse trains. The more intense the stimulus, the higher the pulse frequency, and the closer together the pulses in the train. In this system, a single impulse, or "spike", is trivial, in the sense that it is blank. It cannot convey any information alone. It takes at least two pulses to encode sensory meaning. The information that is read by the brain (meaning, say, a level of light, or the intensity of a musical tone) is encoded as the interval between pulses. And so as students we ate this FM story. And answered the inevitable, standardized questions about it on exams.

Now we learn that this familiar, ingrained bedrock idea is not actually true. Somehow, a single spike is - after all -- capable of conveying information to the brain. This news was not revealed in some single egregious experiment but, rather, by a substantial body of experimental results that have filtered into the literature recently. This book gathers and pivots around this unexpected (and probably very unpopular) body of research work, and I suggest that you initially skip all the introductory material and go straight to pages 54-60, where the experimental literature is summarized.

A nice example comes from studying the decision making time of bats. The animal uses echolocation to navigate in flight. An experimental question is this: How many nerve impulses can the creature's brain have decoded before it suddenly decides to swerve? The answer is on the order of one spike. One. Uno.

At this point in the book, the answer is already transparent. The secret of the neural encoding is that there is no code. A single spike conveys information. The information is explicit. No computation is required to extract it.

Ah, but not so fast. On page 4, the authors reiterate the all-or-none law, declaring that: "... incoming stimuli either produce action potentials, which propagate long distances along the cell's axon, or they do not. There are no intermediate signaling mechanisms. This means that a single neuron can provide information to the brain only through the arrival times of the spikes."

Evidently they still want to keep this absolute intact, and so they go on to recreate, in lieu of the familiar FM neural code, another more sophisticated code. This book is their proposal for a new code.

But it seems to me that having driven such wonderfully high piton (their assertion that the FM code isn't one) the authors proceed to rappel down the mountain very fast. Retreating, perhaps, into their alternative code theory.

Instead of following them to lower, safer ground, you might pause to consider this: There might exist, after all, "intermediate signaling mechanisms." The pulse cannot be amplitude modulated (this really is an absolute). But it can surely do many other clever things that would elude detection by the instruments used to study nerve impulses. (Voltage clamps, patch clamps, probes). Like what? It could spin. It could and probably does travel up the axon membrane in one of many discrete longitudinal channels, formed by protein links between adjacent ion channels. In such a nerve the information, or sensory increment level, is inherent in the channel number.

Neurobiology, as an industry, is somewhat at risk to ideas of the type that are let loose in this remarkable book. If one were to follow up on them, one might arrive at a theory of the brain that actually made sense. Well understood structures like the synapse would have to be explained in new ways, etc. There might be uproar.

Also take a look at Findings and Current Opinion in Cognitive Neuroscience, by Squire and Kosslyn. Chapter 25 reviews some the ideas presented in Spikes, and competing explanations offered by other authors in an effort to elucidate the so called "sparse code." One spike. Very sparse indeed. By all means get a copy of Spikes. It would be a shame to miss out on the scientific revolution it so strongly augers.

5 of 5 people found the following review helpful:

5.0 out of 5 stars Taking the organism's point of view, January 9, 2006

By 

MCMC - See all my reviews

This review is from: Spikes: Exploring the Neural Code (Computational Neuroscience) (Paperback)

What would it mean to understand how a neuron works? Traditionally this questions has been addressed by attempting to solve the encoding problem-that is, given a sample stimulus input, construct a model neuron that predicts the temporal pattern of spikes resulting from observing that stimulus. While much progress has been made on this front (for example, using Weiner-Volterra expansion methods), the remarkable contribution of this book is to turn the question on its head. Instead of asking how a neuron encodes information about the world into discrete spikes, this book instead takes the organism's point of view. Namely, animals do not "observe" the world, but only the spike trains that encode sensory stimuli, and they must be capable of producing successful behavior on the basis of these discrete spikes.

The question for the researcher becomes, given a sample spike train, what do we know about the environmental situation that resulted in this spike train? This question, the decoding problem, is the problem that biological organisms must solve. Perhaps even more remarkably, when posed as a decoding problem, many of the nonlinearities of the neural response disappear, and we are left with a simple linear filtering problem.

`Spikes: Exploring the Neural Code' presents numerous recent results on this front, drawing on behavioral and neurological data as diverse as bat echo location, moth evasion tactics, vertebrate and invertebrate vision, and the incredible French cave beetle capable of reliably detecting temperature changes as small as 1/1000 of a degree. To interpret these results, the authors rely on a variety of mathematical techniques, from probability theory and information theory, to optimal filtering and kernel approaches. This book is very rigorous, and not for math-phobic readers. Understanding all of the ideas presented in this book will take work: about one-third of the book is devoted to a series of appendixes or "Mathematical asides". Finally, one of the most valuable contributions of this book is its extensive list of references for the ideas and results presented in each chapter.