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Recent advances in our understanding of the human brain suggest that adolescence is a unique period of development during which both environmental and genetic influences can leave a lasting impression. To advance the goal of integrating brain and prevention science, two areas of research which do not usually communicate with one another, the Annenberg Public Policy Center's Adolescent Risk Communication Institute held a conference with the purpose of producing an integrated book on this interdisciplinary area. Contributors were asked to address two questions: What neurodevelopmental processes in children and adolescents could be altered so that mental disorders might be prevented? And what interventions or life experiences might be able to introduce such changes? The book deals with the following: biological and social universals in development; characteristics of brain and behavior in development; effects of early maltreatment and stress on brain development; effects of stress and other environmental influences during adolescence on brain development; and reversible orders of brain development.

The Aesthetic Brain takes the reader on a wide-ranging journey addressing fundamental questions about aesthetics and art. Using neuroscience and evolutionary psychology, Chatterjee shows how beauty, pleasure, and art are grounded biologically, and offers explanations for why beauty, pleasure, and art exist at all.

This book examines the history of Western attempts to explain how messages might be sent from the sense organs to the brain and from the brain to the muscles. It focuses on a construct called animal spirit, which would permeate philosophy and guide physiology and medicine for over two millennia. The book's story opens along the Eastern Mediterranean, where it examines how Pre-Socratic philosophers related the soul to air-wind or pneuma. It then traces what Hippocrates, Plato, and Aristotle wrote about this pneuma, and how Stoic and Epicurean philosophers approached it. It also visits Alexandria, where Hellenistic anatomists provided new thoughts about the nerves and the ventricles. Thereafter the book shows how Galen's pneuma psychikon or spiritus animae would provide an explanation for sensations and movements. Galen's writings would guide science and medicine for well over a thousand years, albeit with some modifications. One change, found in early Christian writers Nemesius and Augustine, involved assigning perception, cognition, and memory to different spirit-filled ventricles. The book then turns to how questions began to be raised about it in the 1500s and 1600s. Here it examines the rise of modern science. Nevertheless, the animal spirit doctrine continued to survive because no adequate replacement for it was immediately forthcoming. The replacement theory stemmed from experiments on electric fishes started in the 1750s. Additional research eventually led scientists to abandon their time-honored ideas. The book traces some of the developments leading to modern electrophysiology and ends with an epilogue centered on what this history teaches us about paradigmatic changes in the life sciences.

This is the first book to deal with both the psychological and neurobiological mechanisms in appetites for drugs, food, sex, and gambling, and considers whether there are common factors between them. The book approaches this by looking at the bases of both normal and abnormal appetites in humans.

What is attention? How does it go wrong? Do attention deficits arise from genes or from the environment? Can we cure it with drugs or training? Are there disorders of attention other than deficit disorders? The past decade has seen a burgeoning of research on the subject of attention. This research has been facilitated by advances on several fronts: New methods are now available for viewing brain activity in real time, there is expanding information on the complexities of the biochemistry of neural activity, individual genes can be isolated and their functions identified, analysis of the component processes included under the broad umbrella of “attention” has become increasingly sophisticated, and ingenious methods have been devised for measuring typical and atypical development of these processes, from infancy into childhood, and then into adulthood. This book is concerned with attention and its development, both typical and atypical, particularly in disorders with a known genetic etiology or assumed genetic linkage. Tremendous advances across seemingly diverse disciplines — molecular genetics, pediatric neurology, child psychiatry, developmental cognitive neuroscience, and education s— have culminated in a wealth of new methods for elucidating disorders at multiple levels, possibly paving the way for new treatment options. The book uses three specific-yet-interlinking levels of analysis: genetic blueprint (genotype), the developing brain, and the behavioral-cognitive outcomes (phenotype), as the basis for charting the attention profiles of six well-documented neurodevelopmental disorders: ADHD, autism, fragile X syndrome, Down syndrome, Williams syndrome, and 22_q11 deletion syndrome.

Sound is dynamic and as such has temporal and spectral content. The auditory system extracts the spectral aspects and the temporal ones in parallel in the cochlea and auditory nerve. For frequencies below about 1.5 kHz, the spectral and temporal representations of sound are potentially redundant and both represent the pitch of speech and music. Auditory temporal processing determines our understanding of speech, our appreciation of music, being able to localize a sound source, and to listen to a person in a noisy crowd. The underlying basic capabilities of the auditory system include precise representation of sound onsets and offsets, representing gap durations in sound, and being able to code fast amplitude- and frequency- modulations of sound. The co-occurrence of such onsets and modulations of sound determine auditory objects and allow separating those from other auditory streams. Problems with precise temporal representations of sound occur in auditory neuropathy and multiple sclerosis and lead to a mismatch between auditory sensitivity and speech discrimination. In dyslexia, specific language impairment and auditory processing disorders, similar problems occur early in life and set up additional cognitive speech processing problems. General neurological disorders such as autism, schizophrenia and epilepsy, display temporal processing deficits, generally though as a result of local and global neural synchrony problems. These synchrony problems are reflected in various cortical rhythm abnormalities and lead to cognitive dysfunctions. They also present auditory temporal processing problems, particularly in the amplitude modulation domain.

A Bayesian approach can contribute to an understanding of the brain on multiple levels, by giving normative predictions about how an ideal sensory system should combine prior knowledge and observation, by providing mechanistic interpretation of the dynamic functioning of the brain circuit, and by suggesting optimal ways of deciphering experimental data. This book brings together contributions from both experimental and theoretical neuroscientists that examine the brain mechanisms of perception, decision making, and motor control according to the concepts of Bayesian estimation. After an overview of the mathematical concepts, including Bayes theorem, that are basic to understanding the approaches discussed, contributors discuss how Bayesian concepts can be used for interpretation of such neurobiological data as neural spikes and functional brain imaging. Next, they examine the modeling of sensory processing, including the neural coding of information about the outside world, and finally, they explore dynamic processes for proper behaviors, including the mathematics of the speed and accuracy of perceptual decisions and neural models of belief propagation.

This book contains a wide range of information of huge complexity on rat behavior. The book has three objectives. The first objective is to present an introduction of rat behavior. In choosing the rat as the subject species, the book has made the assumption that this species will remain, as it has in the past, the primary subject used the laboratory investigations of behavior. The second objective is to describe the organization and complexity of rat behavior. The major theme emerging from many lines of research on rat behavior is that understanding the rules of behavioral organization will be central in understanding the structural basis of behavior. The third objective is to update, as much as is possible, previous compendiums of rat behavior. Behavioral neuroscience continues to be a diverse field of research in which there remain many competing experimental methods and hypotheses. The behavioral descriptions in this book are closely tied to the laboratory methods from which they were derived, thus allowing investigators to exploit both the behavior and the methods for their own research. The first part of the book includes sections on natural history, sensory systems, motor systems, regulatory systems, development and parental behavior, social behavior, cognitive functions, and models. The second section is comprised by the major tests used by scientists interested in each domain of behavior.

This book offers a critical exploration of the influential and pervasive belief that “we are our brains” (and that therefore he neurosciences will provide the key to all human phenomena). Since the 1990s, “neurocentrism” has become widespread in most Western and many non-Western societies. Advances, especially in neuroimaging, decisively bolstered it and helped justify increased funding for the brain sciences. Such a belief permeates many other contexts beyond basic research. Major national health agencies consider that “mental” illnesses are “brain disorders.” People diagnosed with some of those disorders advocate “neurodiversity” rights. In the human sciences, subspecialties such as neuroanthropology, neuroaesthetics, neuroeducation, neurohistory, neurolaw, neurosociology or neurotheology quickly professionalized. Dubious businesses, aimed for example at building neuroimaging lie detectors, selling (“neuromarketing”), or promoting wellbeing thanks to regimens said to target the brain (“neurobics”), became successful. The media has showered attention on all things “neuro,” and novels and films rehearsed the challenges of seeing persons as “cerebral subjects.” Skeptics have reacted to the “neurohype,” and spoken of neuromythology, neurotrash, neuromania or neuromadness. The neurocentric view of the human is not hegemonic or monolithic, but embodies a powerful ideology that is at the heart of some of today’s most important philosophical, ethical, scientific and political debates. Why We Are Our Brains critically explores the internal logic of such ideology, its genealogy, and its main contemporary incarnations.

There are many modes of communication that neurons use to transmit information besides what has come to be called neurotransmission. Many of these other types of communication can be classified as neuromodulatory, where instead of conveying excitation or inhibition, the signal from one neuron changes the properties of other neurons or synapses. This form of neuronal communication is often overlooked by systems physiologists, but it is extremely prevalent in the nervous system and needs to be included in any description of how the nervous system processes information. This book provides the foundations for understanding the cellular and molecular basis for neuromodulatory effects. It illustrates some key examples of the roles played by neuromodulation in sensory processing, neuromuscular transmission, generation of motor behaviours, and learning. Finally, the book seeks to point out areas that are likely to be of importance in the future study of information processing by the nervous system. It also summarizes a vast amount of research, and puts it into the context of how these cellular mechanisms are used in systems of neurons. By spanning the levels of analysis from sub-cellular mechanisms through cellular properties and neuronal systems to behaviour, the book provides a framework for understanding this currently exploding field of research.

This book looks at the application of engineering science and technology to biological cells and tissues that are electrically conducting and excitable. It describes the theory and a wide range of applications in both electric and magnetic fields. The similarities and differences between bioelectricity and biomagnetism are described in detail from the viewpoint of lead field theory. This book aims to help with the understanding of the properties of existing bioelectric and biomagnetic measurements and stimulation methods, and to aid with the designing of new systems.

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 primary goal of this book is to summarize and synthesize recent advances in the biological study of aggression. Other than maternal aggression, most aggressive encounters among human and non-human animals represent a male proclivity; thus, most of the research in this book describes and discusses studies using the most appropriate murine model: testosterone-dependent offensive inter-male aggression, which is typically measured in resident-intruder or isolation-induced aggression tests. The research emphasizes various molecules that have been linked to aggression tests. It also emphasizes various molecules that have been linked to aggression by the latest gene-targeting and pharmacological techniques. Although the evidence continues to point to androgens and serotonin (5-HT) as major hormonal and neurotransmitter factors in aggressive behavior, recent work with GABA, dopamine, vasopressin, and other factors, such as nitric oxide, has revealed significant interactions with the neural circuitry underlying aggression.

This book presents a simple description of the biological mechanisms that are involved in the determination of sexual orientation in animals and also presumably in humans. Using scientific studies published over the last few decades, it argues that sexual orientation, both homosexual and heterosexual, is under the control of embryonic endocrine and genetic phenomena in which there is little room for individual choice. The book begins with animal studies of the hormonal and neural mechanisms that control the so-called instinctive behaviors and analyzes how this animal work may potentially apply to humans. The book does not focus exclusively on homosexuality, however. Instead, the book acts as a broader guide to the biological basis of sexual orientation, and also discusses important gender differences that may influence sexual orientation.

Scientists' understanding of two central problems in neuroscience, psychology, and philosophy has been greatly influenced by the work of David Hubel and Torsten Wiesel: What is it to see? This relates to the machinery that underlies visual perception, How do we acquire the brain's mechanisms for vision? This is the nature-nurture question as to whether the nerve connections responsible for vision are innate or whether they develop through experience in the early life of an animal or human. This is a book about the collaboration between Hubel and Wiesel, which began in 1958, lasted until about 1982, and led to a Nobel Prize in 1981. It opens with short biographies of both men, describes the state of the field when they started, and talks about the beginnings of their collaboration. It emphasizes the importance of various mentors in their lives, especially Stephen W. Kuffler, who opened up the field by studying the cat retina in 1950, and founded the department of neurobiology at Harvard Medical School, where most of their work was done. The main part of the book consists of Hubel and Wiesel's most important publications. Each reprinted paper is preceded by a foreword that tells how they went about the research, what the difficulties and the pleasures were, and whether they felt a paper was important and why. Each is also followed by an afterword describing how the paper was received and what developments have occurred since its publication. The reader learns things that are often absent from typical scientific publications, including whether the work was difficult, fun, personally rewarding, exhilarating, or just plain tedious. The book ends with a summing-up of the present state of the field.

Aromatase—or estrogen, as it is commonly known—is present in the brain and has been the subject of much recent research, not only with regard to menopause and the dwindling supply of estrogen and its impact on cognition, but the role estrogen in aging and plasticity in the brain. This book provides a review of what is known about aromatase and its distribution and regulation in the brain, and its many effects on behavior. The volume covers research on mammals (from rats to monkeys), as well as work done on birds, reptiles and amphibians, and fishes. Topics range from behavioral effects (genomic) of locally produced estrogen in the brain; aromatase and sexual differentiation; rapid changes in brain aromatase as a result of environmental effects; aromatase and brain repair; the rapid effects of estrogens on behavior; rapid effect of estrogen on sensory (auditory) processing; and a concluding statement on current challenges to research.

We don’t perceive the world and then react to it. We learn to know it from our interactions with it. All inputs that reach the cerebral cortex about events in the brain, the body, or the world bring two messages: one is about these events, the other, travelling along a branch of that input, is an instruction already on its way to execution. This second message, not a part of standard textbook teaching, allows us to anticipate our actions, distinguishing them from the actions of others, and thus providing a clear sense of self. The mammalian brain has a hierarchy of cortical areas, where higher areas monitor actions of lower areas, and each area can modify actions to be executed by the phylogenetically older brain parts. Brains of our premammalian ancestors lacked this hierarchy, but their descendants are still strikingly capable of movement control: frogs can catch flies. The cortical hierarchy itself appears to establish and increase, from lower to higher levels, our conscious access to events. This book explores the neural connections that provide us with a sense of self and generate our conscious experiences. It reveals how much yet needs to be learnt about the relevant neural pathways.

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.

The subject of this book is how the brain works. In order to understand this, it is essential to know what is computed by different brain systems; and how the computations are performed. The aim of this book is to elucidate what is computed in different brain systems; and to describe current computational approaches and models of how each of these brain systems computes. Understanding the brain in this way has enormous potential for understanding ourselves better in health and in disease. Potential applications of this understanding are to the treatment of the brain in disease; and to artificial intelligence which will benefit from knowledge of how the brain performs many of its extraordinarily impressive functions. This book is pioneering in taking this approach to brain function: to consider what is computed by many of our brain systems; and how it is computed. The book will be of interest to all scientists interested in brain function and how the brain works, whether they are from neuroscience, or from medical sciences including neurology and psychiatry, or from the area of computational science including machine learning and artificial intelligence, or from areas such as theoretical physics.