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Hebb’s seminal volume, The Organization of Behavior, was instrumental in helping to organize the field of behavioral neuroscience. From the time that book was published in 1949 through the early 1980s, there was tremendous interest in the neural bases of behavior, particularly cognitive behavior. Admittedly, much of the work in this field was dominated by animal studies, but that was a product of the methods available at the time (a point repeatedly stressed to the first author of this volume by his undergraduate advisors at McGill, when he expressed interest in studying the relation between brain and behavior in the human child).
This began to change, however, in the mid 1980s as excitement grew over a noninvasive new tool believed to be capable of peering into the human brain. This tool, Positron Emission Tomography (PET), exploded into the scientific mainstream with the seminal publication by Michael Posner and Marcus Raichle and their colleagues at Washington University. In a paper this group published in 1988 (Posner, Petersen, Fox, and Raichle, 1988), it became clear that it was possible to ascertain where processes underlying complex thought (in this case, attention) were taking place in the brain.
Closely monitoring this change was the James S. McDonnell Foundation. Anticipating the partial merger of three distinctive fields—cognitive psychology, neuroscience, and computational science—the Foundation recognized the need to train scientists in the language of these three fields. To do so, they funded what became known as the Summer Institute in Cognitive Neuroscience. In some small way the impetus for this book began over a decade ago, in 1988, in Cambridge, Massachusetts, when the first author of this volume attended the inaugural Summer Institute (the agenda for which is reproduced at the end of this Introduction). This first meeting was brilliantly organized by Michael Posner, Gordon Shepherd, and Stephen Kosslyn, and graciously hosted by Harvard University. For two full weeks it brought to an audience of graduate students, postdocs, and junior faculty an outstanding panel of scientists. Labs were interspersed with lectures, which were interspersed with hallway conversation, collectively making this a very high caliber intellectual endeavor.
One element of this meeting that was particularly memorable, however, was what was not discussed, at least not formally: the study of development. Clearly the work of Jay McClelland, David Hubel, and many others who presented at the Summer Institute had implications for development, but development as development received little formal attention. An exception was a small breakout session on the development of memory that Stephen Kosslyn and Michael Posner (who themselves have long been interested in this topic) asked the author and a number of other attendees to organize. With this one exception, development received little discussion at the meeting.
Through the late 1980s into the 1990s, the field of cognitive neuroscience took hold. The Summer Institutes continued and flourished, the Cognitive Neuroscience Society and the Journal of Cognitive Neuroscience were launched, and psychology departments throughout the United States began to advertise for faculty positions in this field. However, interest in the neural underpinnings of development occurred very slowly. There are many reasons for this trend (for discussion, see Nelson and Bloom, 1997), but suffice to say that change began to occur on three fronts. One was that through the 1980s the field of developmental neuroscience began to yield discoveries of profound importance (e.g., the pattern of synaptogenesis; the role of experience in influencing brain development). A second was that a number of prominent cognitive neuroscientists who had historically studied mature function acknowledged the importance of studying development (e.g., in the mid 1990s a meeting of the Cognitive Neuroscience Society devoted a symposium to developmental cognitive neuroscience). Finally, a new generation of developmental psychologists began to recognize the need for considering the neurobiological underpinnings of behavioral development (again, see Nelson and Bloom, 1997 for discussion). Collectively, then, the time was right for the field of developmental cognitive neuroscience to be born (approximately 16 years after Michael Gazzaniga's first Handbook of Cognitive Neuroscience was published).
This Handbook of Developmental Cognitive Neuroscience represents the distillation of the best this new field has to offer; it also reflects a number of strong biases by the editors. One such bias is that the field of developmental cognitive neuroscience must be grounded in basic neurodevelopmental science, particularly developmental neurobiology. To this end, the first part of this volume (Fundamentals of Developmental Neurobiology) is devoted to basic studies and principles of neural development. Here the reader learns about pre- and postnatal neurogenesis, synaptogenesis, and myelination; the effects of sex hormones on brain development; and about development of the hippocampus and prefrontal cortex in particular (given the importance of these regions for cognitive development). A second bias is our emphasis on the importance of methodological advances. Thus, the second part of the volume (Methodological Paradigms) is devoted to describing methods that have proved so important in elucidating brain–behavior relations in the context of cognitive development. These methods include behavioral “marker” tasks, along with event-related potentials (ERPs), functional Magnetic Resonance Imaging (fMRI), and genetic and computational (neural network) modeling.
Over the past several years the area of neural plasticity has received tremendous attention by both neuroscientists and behavioral scientists. Indeed, the forces that shape and mold the brain may well represent the “new” developmental psychology, albeit a more mechanistic and reductionistic version than offered by previous generations of developmental psychologists and one that emphasizes development within a lifespan context. That is, the forces that mold the brain’s structure and physiology are now recognized to operate well into adulthood (see Tanapat, Hastings, and Gould, chapter 7, this volume). To this end, the third part (Neural Plasticity of Development) is devoted to a discussion of this area, emphasizing both normative and atypical aspects of development.
Because the development of sensory and sensorimotor systems and language has played such a prominent role in both neuroscience and in developmental psychology, the fourth (Sensory and Sensorimotor Systems) and fifth (Language) parts of this volume are devoted to this area. Here we are enlightened about the development of the visual and auditory systems, the development of skilled motor movements, and several aspects of language development. Embedded within these chapters is yet another bias of the editors: the need to juxtapose the study of normative development against that of atypical development, as each mutually informs the other.
The sixth part of the book (Cognition) reflects the substance of the volume, as befits a book on cognitive neuroscience. Here we provide chapters on the development of attention, memory, face/object recognition, spatial cognition, number comprehension, and executive functions. Naturally, the work captured by the distinguished authors of these chapters is framed in a neuroscience context.
The seventh part of this volume (Neurodevelopmental Aspects of Clinical Disorders) returns the reader to the theme of how studies of atypical development can inform the study of typical development. However, these chapters directly target studies of atypical populations. We introduce the reader to the importance of nutrition on brain–behavioral development, on the risks of prenatal alcohol and cocaine exposure, on the development of autism, Tourette's syndrome, and schizophrenia, and on disorders of attention.
The eighth and final part of the book (Emotion and Cognition Interactions) anticipates what may well represent the next cutting edge area, that of developmental affective neuroscience and the manner in which affective experience may act to shape cognitive processes. This part begins with a tutorial on the neurobiology of attachment, and progresses to a discourse on the effects of deprivation on emotional development, on the neurobiology of temperament, and on reward-seeking behavior.
Overall, this volume possesses the breadth and depth necessary to do justice to this exciting new scientific field. It does so by drawing on internationally known experts who have graciously contributed their time and energy to bring the reader the first complete Handbook of Developmental Cognitive Neuroscience. We hope that you are as pleased with the result as we are.
Charles A. Nelson
Monica Luciana
