The Parallel Brain: The Cognitive Neuroscience of the Corpus Callosum (Issues in Clinical and Cognitive Neuropsychology) (Issues in Clinical and Cognitive Neuropsychology Series)

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 brains 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. Introduction: Poffenberger's Simple Reaction Time Paradigm For Measuring Interhemispheric Transfer Time / Eran Zaidel And Marco Iacoboni -- I. Anatomy And Morphometry Of The Corpus Callosum -- 1. Callosal Axons And Their Development / Giorgio M. Innocenti And Raymond Bressoud -- Commentary 1.1. The Effects Of Early Injury To The Cortical Plate On Callosal Connectivity / Glenn D. Rosen -- Commentary 1.2. Binocular Input Elimination And The Reshaping Of Callosal Connection / Maurice Ptito And Denis Boire -- 2. Corpus Callosum Morphology In Relation To Cerebral Asymmetries In The Postmortem Human / Francisco Aboitiz, Andres Ide And Ricardo Olivares -- Commentary 2.1. Complexity Of Human Interhemispheric Connections / Stephanie Clarke -- 3. Brain Size: A Possible Source Of Interindividual Variability In Corpus Callosum Morphology / Lutz Jancke And Helmuth Steinmetz -- Commentary 3.1. Size Differences In The Callosum: Analysis Beyond The Main Effects / Patricia E. Cowell --^ Commentary 3.2. Individual Differences In Corpus Callosum Morphometry: To Normalize Or Not To Normalize For Brain Size / Jeffrey M. Clarke -- 4. Morphometrics For Callosal Shape Studies / Fred L. Bookstein -- 5. Mapping Structural Alterations Of The Corpus Callosum During Brain Development And Degeneration / Paul M. Thompson, Katherine L. Narr, Rebecca E. Blanton And Arthur W. Toga -- Editorial Commentary 1. New Insights In Callosal Anatomy And Morphometry / Eran Zaidel And Marco Iacobone -- Ii. Physiological Aspects Of Callosal Sensorimotor Integration -- 6. Functions Of The Corpus Callosum As Derived From Split-chiasm Studies In Cats / Maurice Ptito -- Commentary 6.1. The Midline Fusion Hypothesis Is All Right But Cannot Explain All Callosal Functions / Giovanni Berlucchi -- 7. Forebrain Commissures: Glimpses Of Neurons Producing Mind / Robert W. Doty --^ Commentary 7.1. From The Physiology Of Callosal Connections To The Understanding Of The Mind: Still A Long Way To Go / Giovanni Berlucchi -- 8. Interhemispheric Visuomotor Activation: Spatiotemporal Electrophysiology Related To Reaction Time / Clifford D. Saron, John J. Foxe, Gregory V. Simpson And Herbert G. Vaughan, Jr. -- Commentary 8.1. Interhemispheric Transfer Of Visual Information As A Function Of Retinal Eccentricity: Evidence From Event-related Potentials / Carlo Miniussi, Angelo Maravita And Carlo Marzi -- Commentary 8.2. Neuroimaging Patterns Of Intra- And Interhemispheric Connectivity / Marco Iacoboni And Eran Zaidel -- Commentary 8.3. The Use Of Event-related Potentials For Measuring Interhemispheric Transfer Time / Steven Berman -- Editorial Commentary 2. Current Directions In Physiological Studies Of Callosal Functions / Margo Iacoboni And Eran Zaidel -- Iii. Interhemispheric Sensorimotor Integration: Behavioral Studies --^ 9. The Evolution Of The Concept Of Interhemispheric Relay Time / Claude M.j. Braun, Andre Achim And Caroline Larocque -- Commentary 9.1. Does The Cud In Srt Measure Ihtt? Or: Is The Crossed-uncrossed Difference In The Simple Reaction Time Task A Pure Measure Of Interhemispheric Transfer Time? / Eran Zaidel And Marco Iacoboni -- Commentary 9.2. Interacting Hemispheres: A Means Of Modulating Attention / Marie T. Banich -- 10. The Corpus Callosum Equilibrates Hemispheric Activation / Marcel Kinsbourne -- Commentary 10.1. A Plan For The Empirical Evaluation Of The Coactivation/equilibration Model Of Callosal Function / Jacqueline Liederman -- 11. Effects Of Partial Callosal And Unilateral Cortical Lesions On Interhemispheric Transfer / Carlo A. Marzi, L.g. Bongiovanni, Carlo Miniussi And Nicola Smania -- Commentary 11.1. Interhemispheric Transfer Of Visuomotor Inputs In A Split-brain Patient: Electrophysiological And Behavioral Indexes / Alice Mado Proverbio And Alberto Zani --^ 12. Stable And Variable Aspects Of Callosal Channels: Lessons From Partial Disconnection / Marco Iacoboni And Eran Zaidel -- Commentary 12.1. Attentional Modulation Of Interhemispheric Transfer: A Two-channel Threshold Model / Kenneth Hugdahl -- 13. Sensorimotor Integration In The Split Brain / Eran Zaidel And Marco Iacoboni -- Commentary 13.1. Water Under The Bridge: Interhemispheric Visuomotor Integration In A Split-brain Man / Michael C. Corballis And Bettina Forster -- 14. Parallel Processing In The Bisected Brain: Implications For Callosal Function / Patricia A. Reuter-lorenz -- Commentary 14.1. In Search Of Lost Time: Functional Significance Of Crossed-uncrossed Differences In Callosal Patients / Marco Iacoboni And Eran Zaidel -- 15. Agenesis Of The Corpus Callosum / Maryse C. Lassonde, Hannelore C. Sauerwein And Franco Lepore -- Commentary 15.1. Sensorimotor Interaction In Agenesis Of The Corpus Callosum / Marco Iacoboni, Mayim H. Bialik And Eran Zaidel --^ Commentary 15.2. Cerebral Plasticity In Callosal Agenesis Versus Callosotomy / Jeffrey M. Clarke -- Commentary 15.3. Interhemispheric And Intrahemispheric Mechanisms Of Visuomotor Integration In Callosal Agenesis / Marirosa Di Stefano And Carla Salvadori -- Editorial Commentary 3. Current Directions In Behavioral Studies Of Callosal Functions / Eran Zaidel And Marco Iacoboni -- Iv. The Corpus Callosum And Clinical Investigations -- 16. Clinical Neuropsychological Assessment Of Callosal Dysfunction: Multiple Sclerosis And Dyslexia / Warren S. Brown -- Commentary 16.1. Interhemispheric Conduction Delay In Multiple Sclerosis / Francesco Tomaiuolo, Marco Iacoboni, M. Altieri, Vittorio Di Piero, Carlo Pozzilli, Gian L. Lenzi And Carlo A. Marzi -- Commentary 16.2. Redundancy Gain As A Measure Of Implicit Sensorimotor Integration / Marco Iacoboni And Eran Zaidel --^ 17. Alexithymia As A Consequence Of Impaired Callosal Function: Evidence From Multiple Sclerosis Patients And Normal Individuals / Michel Habib, Geraldine Daquin, Jean Pelletier, Michelle Montreuil And Fabrice Robichon -- 18. Functional Consequences Of Changes In Callosal Area In Tourette's Syndrome And Attention Deficit/hyperactivity Disorder / M. Yanki Yazgan And Marcel Kinsbourne -- 19. Using The Corpus Callosum As An Effective Anatomical Probe In The Study Of Schizophrenia / Patricia E. Cowell, Victor Denenberg, Gary Boehm, Andrew Kertesz And Henry Nasrallah -- 20. Interhemispheric Abnormalities In Schizophrenia And Their Possible Etiology / Robert W. Doty -- Editorial Commentary 4. Current Directions In Clinical Studies Of Callosal Functions / Eran Zaidel And Margo Iacoboni -- V. From Anatomy To Behavior: The Case Of Pure Alexia -- 21. The Role Of Homotopic And Heterotopic Callosal Connections In Humans / Stephanie Clarke --^ Commentary 21.1. Learning To Read And Write Shapes The Anatomy And Function Of The Corpus Callosum / Alexandre Castro-caldas, Alexandra Reis, Pedro Cavaleiro Miranda And Eduardo Ducla-soares -- 22. Optic Aphasia And Pure Alexia: Contribution Of Callosal Disconnection Syndromes To The Study Of Lexical And Semantic Representation In The Right Hemisphere / Claudio G. Luzzatti -- Commentary 22.1. Right Hemisphere Contributions To Word Recognition In Pure Alexia / Elisabetta Ladavas -- Commentary 22.2. Right Hemisphere Contributions To Residual Reading In Pure Alexia: Evidence From A Patient With Consecutive Bilateral Strokes / Paolo Bartolomeo, Anne-catherine Baghoud-levi, Jean-denis Degos And Francois Boller -- Commentary 22.3. Letter-by-letter Reading: Regional Cerebral Blood Flow Correlates / Marco Iacoboni, Patrizia Pantano And Vittoria Di Piero -- Editorial Commentary 5. The Case Study Of Pure Alexia: Sensorimotor Integration In The Split Brain / Eran Zaidel And Marco Iacoboni. Eran Zaidel And Marco Iacoboni, Editors. A Bradford Book. Includes Bibliographical References And Index. An overview of the central role in cognitive neuroscience of the corpus callosum, the bands of tissue connecting the brain's two hemispheres.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.