Hemispheric specialization is involved in every aspect of sensory, cognitive, and motor systems integration. Study of the corpus callosum, the bands of tissue uniting the brain's two hemispheres, is central to understanding neuroanatomy, neurophysiology, and behavior. It also brings the tools of hemispheric specialization to a fundamental problem of cognitive neuroscience: modularity and intermodular communication.
This book summarizes current research on the human corpus callosum. It also provides a comprehensive introduction to cognitive neuroscience. Rather than viewing the field through the various systems of the mind/brain such as perception, action, emotion, memory, language, and problem solving, it takes a case studies approach. Focusing on the central problem of simple reaction time, it examines the most basic possible sequence of perception-decision-action. The task is to press a button with one hand as soon as a patch of light is detected in the peripheral visual field. When the patch appears in the visual field opposite the responding hand, there must be interhemispheric transfer prior to response. But transfer of what—a visual input code? A cognitive decision code? A motor response code? Combining animal models, normal human studies, and clinical evidence, the authors apply anatomical, physiological, and behavioral perspectives to this question. The emerging view is that the corpus callosum consists of many parallel interhemispheric channels for communication and control, and that every transfer channel is context-dependent and modulated by attention.
About the Editors
Eran Zaidel is Professor of Behavioral Neuroscience and of Cognition in the Department of Psychology at the University of California, Los Angeles, and a member of UCLA’s Brain Research Institute.
Marco Iacoboni is Associate Professor and Director of the Transcranial Magnetic Stimulation Lab at the UCLA Brain Mapping Center. He is also a member of the Brain Research Institute and of the Center for Culture, Brain, and Development at UCLA.
"After the great excitement that followed the work of Roger Sperry on split-brain patients, corpus callosum research progressively faded away as a hot topic in cognitive neuroscience. Zaidel and Iacoboni's book will give a great boost in reinstating the problem of hemispheric specialization as a central one in cognitive neuroscience. It points out a variety of interesting problems that the corpus callosum approach allows one to address, and summarizes many of the most important contributions in this field. The commentaries following the main articles are especially valuable. They give the reader a sense of how lively and interesting the issues are, and one hopes that they will be the catalyst for additional research in the field."—Giacomo Rizzolatti, Institute of Neurophysiology, University of Parma
"How the two hemispheres of the brain communicate and interact and the dysfunctions that occur in interhemispheric communication with specific psychiatric and cognitive abnormalities are crucial topics for understanding higher brain function. The Parallel Brain provides the most comprehensive review of this literature to date and is a must-read for anyone interested in brain asymmetry and interhemispheric interaction. This volume will be indispensable to students and scholars for years to come.
—Richard J. Davidson, William James and Vilas Research Professor of Psychology and Psychiatry, University of Wisconsin—Madison