Synaptic Self: How Our Brains Become Who We Are [Hardcover]

Joseph LeDoux (Author)

Book Description

Release date: January 14, 2002

Ranging widely through philosophy, literature, and the history of science, LeDoux examines how we have conceptualized the relationship between brain and self through the centuries. His own contribution, based on two decades of research, begins with the startlingly simple premise that the self-the essence of who a person is-intricately reflects patterns of interconnectivity between neurons in the brain. Synapses, the spaces between neurons, are not only the channels through which we think, act, imagine, feel, and remember, but also the means by which we encode our most fundamental traits, preferences, and beliefs, allowing us to function as a single, integrated individual-a synaptic self.

As LeDoux brilliantly argues, a synaptic self does not exclude other ways of understanding existence-spiritual, aesthetic, moral-but rather it enriches and broadens these avenues by providing a neurological/psychological construct grounded in the latest research in biology. Rather than join the age-old debate on whether nature or nurture is more determinative, LeDoux posits that both genes and experience contribute to synaptic connectivity. Mind expanding in every sense of the word, Synaptic Self represents an important breakthrough in one of the last frontiers of medical research.

Editorial Reviews

Amazon.com Review

A middle-aged neuroscientist walking down Bourbon Street spots a T-shirt that reads, "I don't know, so maybe I'm not." This stimulus zooms from eyes to brain, neuron by neuron, via tiny junctions called synapses. The results? An immediate chuckle and (sometime later) a groundbreaking book titled The Synaptic Self. To Joseph LeDoux, the simple question, "What makes us who we are?" represents the driving force behind his 20-plus years of research into the cognitive, emotional, and motivational functions of the brain.

LeDoux believes the answer rests in the synapses, key players in the brain's intricately designed communication system. In other words, the pathways by which a person's "hardwired" responses (nature) mesh with his or her unique life experiences (nurture) determine that person's individuality. Here, LeDoux nimbly compresses centuries of philosophy, psychology, and biology into an amazingly clear picture of humanity's journey toward understanding the self.

Equally readable is his comprehensive science lesson, where detailed circuit speak reads like an absorbing--yet often humorous--mystery novel. Skillfully presenting research studies and findings alongside their various implications, LeDoux makes a solid case for accepting a synaptic explanation of existence and provides to the reader generous helpings of knowledge, amusement, and awe along the way. --Liane Thomas

From Publishers Weekly

Despite ongoing debate about the root cause of psychological disorders, most agree that the development of the self is central to the distinction between normality and psychopathology. Yet neuroscientists have been slow to probe the biological basis for our sense of self, focusing instead on states of consciousness. LeDoux (The Emotional Brain), professor at New York University's Center for Neural Sciences, has come up with a theory: it's the neural pathways the synaptic relationships in our brains that make us who we are. Starting with a description of basic neural anatomy (including how neurons communicate, the brain's embryological development and some of the key neural pathways), LeDoux reviews experiments and research, arguing that the brain's synaptic connections provide the biological base for memory, which makes possible the sense of continuity and permanence fundamental to a "normal" conception of self. Writing for a general audience, he succeeds in making his subject accessible to the dedicated nonspecialist. He offers absorbing descriptions of some of the most fascinating case studies in his field, provides insight into the shortcomings of psychopharmacology and suggests new directions for research on the biology of mental illness. While some may disagree with LeDoux's conclusion that "the brain makes the self" through its synapses, he makes an important contribution to the literature on the relationship between these two entities. Agents, Katinka Matson and John Brockman. (On-sale: Jan. 14)

Copyright 2001 Cahners Business Information, Inc.

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Product Details

• Hardcover: 406 pages
• Publisher: Viking Adult (January 14, 2002)
• Language: English
• ISBN-10: 0670030287
• ISBN-13: 978-0670030286
• Product Dimensions: 9.1 x 6.5 x 1.4 inches
• Shipping Weight: 1.6 pounds
• Average Customer Review: 4.2 out of 5 stars  See all reviews (48 customer reviews)
• Amazon Best Sellers Rank: #241,383 in Books (See Top 100 in Books)

More About the Author

Joseph LeDoux is Henry and Lucy Moses Professor of Science at New York University's Center for Neural Sciences. He is the author of Synaptic Self, The Emotional Brain: The Mysterious Underpinnings of Emotional Life and coauthor (with Michael Gazzaniga) of The Integrated Mind.

Most Helpful Customer Reviews

167 of 170 people found the following review helpful

4.0 out of 5 stars painless intro to synaptic structure and biochemistry August 15, 2003

By R. M. Williams

Format:Hardcover

The book is an introduction to neurology from the particular viewpoint of the synapse and associated biochemistry. The author's specific interest in the field is experimental research into fear circuits in the brain, and the book shows this interest well and it forms the bulk of the examples. It is not the first book in the field that i would recommend to someone just getting interested, it is an "advanced intro" if that is possible, just a little hard going if you have no idea of the terminology or general structures. But it is written to the educated laymen, doesn't require a college degree to understand it, and is a welcome addition to my expanding library on the philosophy of the mind.

The book is well written, flows nicely until the near end,(drags a little just after chapter 6 however, that is why a 4 not a 5 rating) i'd recommend "synaptic sickness" be moved to an appendix if it couldn't be integrated into the body of the book better. The scholarly apparatus is kept to a minimum yet the push to ratify/justify the new knowledge via experimental data and reference to other scientists work is clearly evident and makes the book a good intro to the field, as further study is facilitated. I found the use of concrete experimental examples and the prolific use of diagrams (especially figures 6.4 - 6.6) particularly good(very superior), the book was always engrossing and a stimulating read, not common in books written by scientists who are not teachers as well.

As to particularly important ideas: i would point to chapter 6= "small change" and the systematic analysis of Hebbian plasticity and how long-term potentiation supplies the synaptic justification for memory and learning the key chapter in the whole book. The chapters before are introductory prologue to this idea, and the chapters subsequent are particular examples of how Hebbian plasticity and synaptic change unlie the circuits of the brain and hence become who we are.

And unusual emphasis(compared to the field as a whole) is on the emotional side of the triad: cognition, emotion, motivation, this is due to the author's interest and last book as a result of his professional research into fear circuitry. I appreciate the emphasis as a long overdue correction to neurology being somewhat, like philosophy of the mind, concentrated on the cognition part of the equation. With this emphasis and direction much of the book dedicated to showing fear circuits and like analysis means this ends up with teaching you a wider view of the brain than most introductory books. A good thing.

So i wholehearted recommend the book to anyone who had the patience and interest to finish reading this review. thanks.

99 of 108 people found the following review helpful

5.0 out of 5 stars LeDoux's Synaptic Self is wonderful ! March 23, 2002

By Shelley Hussey

Format:Hardcover

LeDoux starts his first chapter with a quote from Bart Simpson: "Dad, what is the mind? Is it just a system of impulses or something tangible?" My kind of humor.

LeDoux's Synaptic Self is a wonderful book loaded with clear understandable explanations and insights (his wife, a "fantastic writer," assisted) on how the brain works based on the most current neuroscience (e.g., how neurons/synapses/neurotransmitters/neuro modulators work/don't work, implicit/explicit learning/memory mechanism explanations, nature/nurture considerations, the "mental trilogy" of cognition/emotion/motivation, and much more). The book's bottom-line, he writes, is "you are your synapses." With this book, "know thyself," and even fix thyself, seem more attainable. It's a book I'll reread/study for a while.

The following are quotes from the last chapter:

Life requires many brain functions, functions require systems, and systems are made of synaptically connected neurons. We all have the same brain systems, and the number of neurons in each brain system is more or less the same in each of us as well. However, the particular way those neurons are connected is distinct, and that uniqueness, in short, is what makes us who we are.

What is remarkable is that synapses in all of these systems are capable of being modified by experience... Emotion systems [as an example]... are programmed by evolution to respond to some stimuli, so-called innate or unconditioned stimuli, like predators or pain. However, many of the things that elicit emotions in us or motivate us to act in certain ways are not preprogrammed into our brains as part of our species heritage but have to be learned by each of us. Emotion systems learn by association - when an emotionally arousing stimulus is present, other stimuli that are also present acquire emotion-arousing qualities (classical conditioning), and actions that bring you in contact with emotionally desirable stimuli or protect you from harmful or unpleasant ones are learned (instrumental conditioning.) As in all other types of learning, emotional associations are formed by synaptic changes in the brain system involved in processing the stimuli. Some of the brain's plastic emotional processors include systems involved in detecting and responding to danger, finding and consuming food, identifying potential mates and having sex.

Because synaptic plasticity occurs in most if not all brain systems, one might be tempted to conclude that the majority of brain systems are memory systems. But [as LeDoux argues in chapter 5], a better way of thinking about this is that the ability to be modified by experience is a characteristic of many brain systems, regardless of their specific function. Brain systems, in other words, were for the most part not designed as storage devices - plasticity is not their main job assignment. They were instead designed to perform particular tasks like processing sounds or sights, detecting food or danger or mates, controlling actions, and so on. Plasticity is simply a feature that helps them do their job better.

Functions depend on connections: break the connections and you lose the functions...

From LeDoux's Synaptic Self

135 of 150 people found the following review helpful

4.0 out of 5 stars Good pop neuroscience April 22, 2003

By Carlos Camara

Format:Hardcover

This book is as good as a popular science book can be, and explains in easy terms some of the most important concepts in neuroscience. For this it should be widely read. However, Ledoux wants to explain the self, and not only to write a popular book on cognitive neuroscience. Now, given that it is very difficult not to accept that the self at some level is nothing but synapses, Ledoux does seem to base the self on neurobiological mechanisms. But this is no more enlightening than sayying that vision, attention, language, or even qualia are nothing but synapses, claims that at some level must also be correct. So one would expect the bulk of the book to develop principles that tie or at least correlate the self with brain mechanisms. Do we get this in Synaptic Self? well, yes and no.

Ledoux concentrates on memory, having in his last book focused on emotion. He explains memory systems from molecules to circuits, with the classical and most recent findings, including some from his own lab. He also gives a quick overview of the emotional systems of the brain, the working memory complex of the prefrontal cortex, and motivational systems of neuromodulator and brainstem and thalamocortical systems. He calls that the mental trilogy, namely cognition, emotion and motivation. Ledoux also wrote a nice chapter on some brain diseases that seem to alter these functions selectively. And thats it. Ledoux has explained the self. Or has he? Well, memory, emotion, cognition and motivation surely contribute to the making of the self, especially memory. How much of a self is left in a retrograde and anterograde severe amnesic? But this is not saying that putting them together is all the self is about. Its like saying vision, attention and waking are what consicousness is. Vision provides content, attention access, and waking a necesary condition for consicousness, but together they are not the phenomenon in question. I bring out consicousness because Ledoux says the really hard and important question in neuroscience is the self, and not consciousness. To me it seems almost silly to try to understand the former without the latter.

Ledoux then forgets about the feeling of the self itself, the possible bases of it on body schemas and body signals, the primacy of movement. He does touch on volition and free will, and is as naturalistic about these issues as one can be, which I think is a good thing. The final chapter presents 7 principles he can extract from his discussions, and meybe here we can find his theory of the self. Unfortunately, he seems just to add another thing, binding, to the picture. So binding, convergence zones, emotion and motivation, memory, placticity, hebbbian mechanisms of memory, together are the self. Again, I would say they are an important part of the self, but not the self itself. I may be wrong or maybe dogmatic about what would count as an explanation for the self. Maybe there is nothing more to the self than those mechanisms Ledoux lists. But work in theorethical neuroscience like by Damasio, or Patricia Churchland and philosophers like Bermudez show that the self is more complex than Ledoux seems to think.

At the end this book is of value, and I never said it did not make progress on the problem of the neurobiology of the self. However, it does not by any means solve it. It presents a nice theory of the integration of cognitive and affective mechanisms, and manages to cover a great deal of issues in simple terms, and that is always an achievement.