A Theory of the Basal Ganglia and Their Disorders

ISBN-13: 9781420058970 / Angielski / Twarda / 2007 / 312 str.

Robert Miller; Robert Miller

Opis

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.

Spis treści

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

O autorze

Robert Miller