1st Edition

A Theory of the Basal Ganglia and Their Disorders

By Robert Miller Copyright 2008
    312 Pages 23 B/W Illustrations
    by CRC Press

    The Basal ganglia, to adopt a phrase of Churchill's, are "a riddle wrapped in a mystery, inside an enigma." And although there is a wealth of information available on them, this research field remains controversial due in part to the diverse number of disciplines involved. A Theory of the Basal Ganglia and Their Disorders provides a clear, coherent view of basal ganglia that integrates evidence from the basic neurosciences, neurology, and psychiatry. The author explores the basal ganglia within a context of the function of the mammalian forebrain as a whole.

    Divided into two parts, the book explores the basic framework in which normal functions of the basal ganglia can be understood, and then moves on to discuss major disorders. It explains, as far as possible, symptoms and related clinical facts in terms of the underlying pathology and pathophysiology. With this goal in mind, the author includes only disorders of the basal ganglia for which there are already clear ideas about the underlying neuropathology or pathophysiology. He also conveys the human experience of these disorders as well as their scientific basis.

    While many books cover cutting-edge research, none have addressed large-scale questions about the role of the basal ganglia as a whole. Until now. This is arguably the only book published in the last 50 years that has attempted to provide an overall theory of the basal ganglia, as well as relevant areas of neurology and psychiatry. It concisely presents the theory, rather than comprehensively covering all the literature, and places the essential clinical facts within a framework formulated for normal operations of the basal ganglia. Presenting a unified view, the book takes several steps toward unraveling the riddle that is basal ganglia.

    THE FRAMEWORK FOR NORMAL BASAL GANGLIONIC FUNCTION
    Introduction: Background to the Dynamics of the Basal Ganglia
    The Cortico-Thalamo-Hippocampal Excitatory Network: Substrate for Cell Assemblies and Associative Operations
    Definition of Executive Functions
    The "Motor Thalamus": Target of Executive Decisions?

    The Striatum: Functional Significance and "Direct" Connectivity to Output Nuclei of the Basal Ganglia
    The Striatum: Detector and Encoder of Motivationally Significant Outcomes of Behavior and Deployer of Motivationally Favorable Behaviors
    Functional Subdivisions within Each Component of the Basal Ganglia
    The "Credit Assignment Problem"
    Morphological Evidence about the Fine Distribution of Connections in the Basal Ganglia
    Cybernetic Interpretations Derived from Quantitative Synaptology
    Collateral Inhibition in the Striatum

    The "Indirect" Pathways from Striatum to Basal Ganglia Output Nuclei, and Their Relation to the "Direct" Pathway
    Overall Patterns of Connectivity
    Segregation versus Overlap of "Direct" and "Indirect" Pathways from Striatum to Thalamus
    The "Credit Assignment Problem" in the Indirect Pathway
    Evidence on the Relative Role of "Direct" and "Indirect" Pathways

    Theories of Basal Ganglionic Function
    Early Theories
    Synopsis of Key Issues
    The "Scaling of Movement" Hypothesis
    The "Focused Selection" Hypothesis
    A More Complete Version of the "Focused Selection" Theory, Including Predictions
    Comparison with an Earlier Theory of the Basal Ganglia: Significance of Cell Assemblies
    Dynamics of Neural Activity in Structures of the Basal Ganglia and the Nature of the Neural Code in These Structures

    Synopsis of Part I and Predictions Derived from It

    INTERPRETATION OF SYMPTOMS OF DISEASES OF THE BASAL GANGLIA
    Introduction
    General Comments
    Neuropathology and Pathophysiology of Disorders of the Basal Ganglia

    Huntington's Disease

    Parkinson's Disease and Parkinsonian Syndromes
    Introduction
    The "Goad and the Halter" in Parkinson's Disease
    Coactivation of Striatal Neurons and Cognitive Problems Associated with Parkinsonian Syndromes
    Inflexibility of Adjustments of Posture and Gait in Parkinson's Disease
    The Role of the Subthalamus in Production of Parkinsonian Symptoms
    Burst Firing in Components of the Basal Ganglia and Parkinsonian Tremor
    Direct Connections from Basal Ganglia to Brain Stem, and Their Role in Parkinsonian Akinesia and Rigidity
    Parkinson's Disease: Summary

    Dopamine-Dependent Psychosis
    Introduction
    Development of the Dopamine Hypothesis of Psychosis
    Neural Dynamics in the Basal Ganglia When Dopaminergic Tone is Elevated
    Overactivity of Striatal Dopamine in Relation to the Symptoms of Psychosis
    Pharmacology of Psychosis
    Positive Feedback between Striatum and Cortex in the Generation of Psychosis

    Syndromes Arising as Complications of Prolonged Underactivity of Striatal Dopamine Mechanism, and Other Disorders of the Basal Ganglia
    Introduction
    Reasons for Identifying Striatal Cholinergic Cell Loss as the Origin of the Four Syndromes
    Phenomenology of Peak Dose Dyskinesia and Tardive Dyskinesia
    Dyskinesias, Stereotypy, Refractory Psychosis and Other Behavioral Pathologies Related to High-Dopamine States without a Prior History of Prolonged Dopaminergic Underactivity
    Pharmacological Theory: Involvement of Dopaminergic and Cholinergic Receptor Subtypes
    Other Disorders Involving the Basal Ganglia

    Synopsis of Part II and Predictions Derived from It
    Appendix 1: Abbreviations
    Appendix 2: Pharmacological Agents and Their Actions References
    Index

    Biography

    Robert Miller

    "Miller’s knowledge of the anatomy of neurological disorders is impressive. Only a person with a lifetime of experience in basal ganglia research could pull together such a wide range of information into a coherent model. We can all be grateful for the work of researchers like Robert Miller who have persevered for so many years in this area and are giving us all a coherent model of basal ganglia function."

    – James J. Jakubow in PsycCRITIQUES, Volume 54, No. 35, 2008