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This book presents a theoretical framework for understanding the regularity of the brain’s perceptions, its reactions to sensory stimuli, and its control of movements. The book offers an account of perception as the combination of prediction and observation: the brain builds internal models that describe what should happen and then combines this prediction with reports from the sensory system to form a belief. Considering the brain’s control of movements, and variations despite biomechanical similarities among old and young, healthy and unhealthy, and humans and other animals, chapters review evidence suggesting that motor commands reflect an economic decision made by our brain weighing reward and effort. This evidence also suggests that the brain prefers to receive a reward sooner than later, devaluing or discounting reward with the passage of time; then as the value of the expected reward changes in the brain with the passing of time (because of development, disease, or evolution), the shape of the movements will also change. The internal models formed by the brain provide it with an essential survival skill: the ability to predict based on past observations. The formal concepts presented by the authors offer a way to describe how representations are formed, what structure they have, and how the theoretical concepts can be tested.

The vast differences between the brain’s neural circuitry and a computer’s silicon circuitry might suggest that they have nothing in common. In fact, as Dana Ballard argues in this book, computational tools are essential for understanding brain function. Ballard shows that the hierarchical organization of the brain has many parallels with the hierarchical organization of computing; as in silicon computing, the complexities of brain computation can be dramatically simplified when its computation is factored into different levels of abstraction. Drawing on several decades of progress in computational neuroscience, together with recent results in Bayesian and reinforcement learning methodologies, Ballard factors the brain’s principal computational issues in terms of their natural place in an overall hierarchy. Each of these factors leads to a fresh perspective. A neural level focuses on the basic forebrain functions and shows how processing demands dictate the extensive use of timing-based circuitry and an overall organization of tabular memories. An embodiment level organization works in reverse, making extensive use of multiplexing and on-demand processing to achieve fast parallel computation. An awareness level focuses on the brain’s representations of emotion, attention and consciousness, showing that they can operate with great economy in the context of the neural and embodiment substrates.

Cannabinoids and the Brain introduces an informed general audience to the scientific discovery of the endocannabinoid system and recent preclinical research that explains its importance in brain functioning. The endocannabinoids, anandamide and 2-AG, act on the same cannabinoid receptors, that are activated by the primary psychoactive compound found in marijuana, Δ‎⁹-tetrahydrocannabinol (THC). Therefore, the scientific investigations of the functions of the endocannabinoid system are guided by the known effects of marijuana on the brain and body. The book reviews the scientific evidence of the role that the endocannabinoid system plays in regulating emotion, anxiety, depression, psychosis, reward and addiction, learning and memory, feeding, nausea/vomiting, pain, epilepsy, and other neurological disorders. Anecdotal reports are linked with the current scientific literature on the medicinal benefits of marijuana. Cannabis contains over 80 chemicals that have closely related structures, called cannabinoids, but the only major mood-altering constituent is THC. Another major plant cannabinoid is cannabidiol (CBD), which is not psychoactive; yet, considerable recent preclinical research reviewed in various chapters reveals that CBD has promising therapeutic potential in treatment of pain, anxiety, nausea and epilepsy. Only recently, has research been conducted with some of the other compounds found in cannabis. The subject matter of the book is extremely timely in light of the current ongoing debate not only about medical marijuana, but also about its legal status.

The notion that neurons in the living brain can change in response to experience—a phenomenon known as “plasticity”—has become a major conceptual issue in neuroscience research as well as a practical focus for the fields of neural rehabilitation and neurodegenerative disease. Early work dealt with the plasticity of the developing brain and demonstrated the critical role played by sensory experience in normal development. Two broader themes have emerged in recent studies: the plasticity of the adult brain (one of the most rapidly developing areas of current research) and the search for the underlying mechanisms of plasticity—explanations for the cellular, molecular, and epigenetic factors controlling plasticity. Many scientists believe that achieving a fundamental understanding of what underlies neuronal plasticity could help us treat neurological disorders and even improve the learning capabilities of the human brain. This book offers contributions from leaders in the field that cover all three approaches to the study of cerebral plasticity. Chapters look at normal development and the influences of environmental manipulations; cerebral plasticity in adulthood; and underlying mechanisms of plasticity. Others deal with plastic changes in neurological conditions and with the enhancement of plasticity as a strategy for brain repair.

Most neurons in the brain are covered by dendritic spines, small protrusions that arise from dendrites, covering them like leaves on a tree. But a hundred and twenty years after spines were first described by Ramón y Cajal, their function is still unclear. Dozens of different functions have been proposed, from Cajal's idea that they enhance neuronal interconnectivity to hypotheses that spines serve as plasticity machines, neuroprotective devices, or even digital logic elements. This book attempts to solve the “spine problem,” searching for the fundamental function of spines. The text does this by examining many aspects of spine biology that been sources of fascination over the years, including their structure, development, motility, plasticity, biophysical properties, and calcium compartmentalization. it argues that we may never understand how the brain works without understanding the specific function of spines. The book offers a synthesis of the information that has been gathered on spines (much of which comes from studies of the mammalian cortex), linking their function with the computational logic of the neuronal circuits that use them. It argues that once viewed from the circuit perspective, all the pieces of the spine puzzle fit together nicely into a single, overarching function. The book connects these two topics, integrating current knowledge of spines with that of key features of the circuits in which they operate. It concludes with a speculative chapter on the computational function of spines, searching for the ultimate logic of their existence in the brain.

A fundamental shift is occurring in neuroscience and related disciplines. In the past, researchers focused on functional specialization of the brain, discovering complex processing strategies based on convergence and divergence in slowly adapting anatomical architectures. Yet for the brain to cope with ever-changing and unpredictable circumstances, it needs strategies with richer interactive short-term dynamics. Recent research has revealed ways in which the brain effectively coordinates widely distributed and specialized activities to meet the needs of the moment. This book explores these findings, examining the functions, mechanisms, and manifestations of distributed dynamical coordination in the brain and mind across different species and levels of organization. It identifies three basic functions of dynamic coordination: contextual disambiguation, dynamic grouping, and dynamic routing. The book considers the role of dynamic coordination in temporally structured activity and explores these issues at different levels, from synaptic and local circuit mechanisms to macroscopic system dynamics, emphasizing their importance for cognition, behavior, and psychopathology.

This book argues that understanding the neural underpinnings of aesthetic experience can reshape our conceptions of aesthetics and the arts. Drawing on the tools of both cognitive neuroscience and traditional humanist inquiry, the book shows that neuroaesthetics offers a new model for understanding the dynamic and changing features of aesthetic life, the relationships among the arts, and how individual differences in aesthetic judgment shape the varieties of aesthetic experience. The book proposes that aesthetic experience relies on a distributed neural architecture—a set of brain areas involved in emotion, perception, imagery, memory, and language. More important, it emerges from networked interactions, intricately connected and coordinated brain systems that together form a flexible architecture enabling us to develop new arts and to see the world around us differently. Focusing on the “sister arts” of poetry, painting, and music, the book builds and tests a neural model of aesthetic experience valid across all the arts. Asking why works that address different senses using different means seem to produce the same set of feelings, the book examines particular works of art in a range of media, including a poem by Keats, a painting by van Gogh, a sculpture by Bernini, and Beethoven's Diabelli Variations.

This book shows new ways of thinking about how the brain relates to the world, to cognition, and to behavior. Based on foundations previously established the book considers the implications of these ground rules for thalamic inputs, thalamocortical connections, and cortical outputs. The book argues that functional and structural analyses of pathways connecting thalamus and cortex point beyond these to lower centers and through them to the body and the world. Each cortical area depends on the messages linking it to body and world. These messages relate to the way we act and think; each cortical area receives thalamic inputs and has outputs to motor centers. The book goes on to discuss such topics as the role of branching axons that carry motor instructions as well as copies of these motor instructions for relay to cortex under the control of the thalamic gate. This gate allows the thalamus to control the passage of information on the basis of which cortex relates to the rest of the nervous system.

This book offers an interdisciplinary approach to the understanding of human memory, with contributions from both neuroscientists and humanists. Linking the neuroscientific study of memory to the investigation of memory in the humanities, it connects the latest findings in memory research with insights from philosophy, literature, theater, art, music, and film. Chapters from the scientific perspective discuss both fundamental concepts and ongoing debates from genetic and epigenetic approaches, functional neuroimaging, connectionist modeling, dream analysis, and neurocognitive studies. The humanist analyses offer insights about memory from outside the laboratory: a taxonomy of memory gleaned from modernist authors including Virginia Woolf, James Joyce, and William Faulkner; the organization of memory, seen in drama ranging from Hamlet to The Glass Menagerie; procedural memory and emotional memory in responses to visual art; music's dependence on the listener's recall; and the vivid renderings of memory and forgetting in such films as Memento and Eternal Sunshine of the Spotless Mind. The chapters from the philosophical perspective serve as the bridge between science and the arts. The book's introduction offers an integrative merging of neuroscientific and humanistic findings.

The human brain is far smarter than a supercomputer but requires 100,000-fold less energy and space. Such efficient information processing is governed by ten principles of design. These apply to the whole brain across the full range of spatial and temporal scales, and to the brains of all species. The principles are: compute with chemistry; compute directly with analog primitives; combine analog and pulsatile processing; code sparsely; send only what information is needed for a particular task; transmit information at the lowest acceptable rate; minimize wire; make neural components irreducibly small; complicate; adapt and match, learn and forget. This approach does not explain the “hows” of brain design but does explain many of the “whys”. For example, it explains why certain signals are sent via hormones and others via nerves; why neural wires are mostly thin with only a few thick; why synapses differ in size, number and reliability according to the circuit that they serve; why every neuron type has a characteristic shape; why the cerebral cortex is parceled into different areas and different layers; why learning couples to forgetting. “Whys” explained on nearly every page. Given the explanatory power of ten principles, we should search for more.

This book proposes a new explanation for the forms of social relations. It argues that the core of social-relational cognition exhibits beauty—in the physicist’s sense of the word, associated with symmetry. The book describes a fundamental set of patterns in interpersonal cognition that account for the resulting structures of social life in terms of their symmetries and the breaking of those symmetries. It further describes the symmetries of the four fundamental social relations as ordered in a nested series akin to what one finds in the formation of a snowflake or spiral galaxy. Symmetry breaking organizes the neural activity generating the cognitive models which structure our social relationships. The book’s primary claim is that there exists a social pattern generator analogous to the central pattern generators associated with locomotion in many animal species. Spontaneous symmetry breaking structures the activity of the social pattern generator just as it does in central pattern generators. The book’s hypothesis that relational cognition results from self-organization is entirely novel, distinct from other theories, which describe sociality in terms of evolution or environment. It presents a picture of social-relational cognition as resembling something inorganic. In doing so, the hypothesis reveals deep connections among cognition, biology, and the inorganic world. One can go too far, the book acknowledges, in taking a solely dynamical view of the mind; the mind’s innate functional complexity must be due to natural selection. But this does not mean that every simple mental feature is the result of natural selection.

This book is the result of an interdisciplinary, two-week international symposium on principles of sensory communication hosted by MIT in July 1959. This symposium brought together prominent neuroscientists, life scientists, physical scientists, and engineers who “were willing to listen to neurophysiologists expound up-to-date neurophysiology, or psychophysicists talk about contemporary psychophysics, without being satisfied with their own version of the other man’s science.” The work presented forms the basis of much of the contemporary research in vision and perceptual science. First published by the MIT Press in 1961, the book has been out of print and extremely difficult to obtain for many years. This reprint makes this resource available again.

In the last decade, the synergistic interaction of neurosurgeons, engineers, and neuroscientists, combined with new technologies, has enabled scientists to study the awake, behaving human brain directly. These developments allow cognitive processes to be characterized at unprecedented resolution: single neuron activity. Direct observation of the human brain has already led to major insights into such aspects of brain function as perception, language, sleep, learning, memory, action, imagery, volition, and consciousness. In this volume, experts document the successes, challenges, and opportunity in an emerging field. The book presents methodological tutorials, with chapters on such topics as the surgical implantation of electrodes and data analysis techniques; describes novel insights into cognitive functions including memory, decision making, and visual imagery; and discusses insights into diseases such as epilepsy and movement disorders gained from examining single neuron activity. Finally, contributors consider future challenges, questions that are ripe for investigation, and exciting avenues for translational efforts.

In recent decades, empathy research has blossomed into a vibrant and multidisciplinary field of study. The social neuroscience approach to the subject is premised on the idea that studying empathy at multiple levels (biological, cognitive, and social) will lead to a more comprehensive understanding of how other people’s thoughts and feelings can affect our own thoughts, feelings, and behavior. In the chapters in this book, leading advocates of the multilevel approach view empathy from the perspectives of social, cognitive, developmental and clinical psychology, and cognitive/affective neuroscience. Chapters include a critical examination of the various definitions of the empathy construct; surveys of major research traditions based on these differing views (including empathy as emotional contagion, as the projection of one’s own thoughts and feelings, and as a fundamental aspect of social development); clinical and applied perspectives, including psychotherapy and the study of empathy for other people’s pain; various neuroscience perspectives; and discussions of empathy’s evolutionary and neuroanatomical histories, with a special focus on neuroanatomical continuities and differences across the phylogenetic spectrum. The new discipline of social neuroscience bridges disciplines and levels of analysis.

Translational neuroscience faces considerable challenges, as available therapies to treat brain and nervous system disorders are extremely limited and dated. Drug efficacy for depression, anxiety, schizophrenia, and bipolar disorder plateaued nearly a half century ago, and further development has all but been abandoned by the pharmaceutical industry. Disinvestment by the private sector has occurred just as promising new technologies in genomics, stem cell biology, and neuroscience have emerged which, if invested in, could initiate a new generation of treatments. This unique paradox clouds the way forward, risking the possibility that new opportunities will not be exploited effectively. In this volume, experts from academia and industry grapple with the central issues involved. These include: (1) putting genomics and neuroscience to work in service of better diagnostics and identification of biomarkers; (2) new approaches to disease models based on stem cell technology and more careful use of animal models; (3) greater attention to human biology and consideration of what it will take to speed toward human administration of new therapeutic candidates. The volume concludes by presenting a conceptual roadmap for an effective and credible translational neuroscience: one that will take us from the bedside to the lab and back again.

Hemispheric asymmetry is one of the basic aspects of perception and cognitive processing. The different functions of the left and right hemispheres of the brain have been studied with renewed interest in recent years, as scholars have explored applications to new areas, new measuring techniques, and new theoretical approaches. This book provides a comprehensive view of the latest research in brain asymmetry, offering not only recent empirical and clinical findings but also a coherent theoretical approach to the subject. In chapters that report on the field at levels from the molecular to the clinical, researchers address such topics as the evolution and genetics of brain asymmetry; animal models; findings from structural and functional neuroimaging techniques and research; sex differences and hormonal effects; sleep asymmetry; cognitive asymmetry in visual and auditory perception; and auditory laterality and speech perception, memory, and asymmetry in the context of developmental, neurological, and psychiatric disorders.