Comparative Neurology of Telencephalon

When a young graduate student sat before Percival Bailey in 1960 and spoke of his longstanding interest in zoology and his recent interest in the nervous system, he asked the then Director of the Illinois Neuropsychiatric Institute if there was support in the scientific establishment for research in evolutionary comparative neurology. Bailey patted his abdomen with both hands and thought for a moment. Finally he said: "Young man, there is no place for people like you." The graduate student was crestfallen. To a large extent what Bailey said is still true. The greater part of research in neurobiology is directed toward answering a single broad question. How do brains in general, and the human brain in particular, work? This is a legitimate and important question. It is not, however, the only question worth answering. This overweening emphasis on function, especially in regard to the human nervous is a result of the origins of neurology in the clinic. The professional school, system, site of most such research, has been remarkably well-insulated from many of the major concerns of biology.

Table of Contents:
1 On the Organization of the Telencephalon in Elasmobranchs.- I. Introduction.- II. Organization of Elasmobranchs.- III. Brain Weight-Body Weight Ratio.- IV. Telencephalic Organization in General.- V. Olfactory Input.- VI. Visual Input.- VII. Representation of Other Sensory Systems in the Telencephalon.- VIII. Telencephalic Efferent Pathways.- IX. Conclusion.- X. References.- 2 Telencephalic Function in Elasmobranchs: A Behavioral Perspective.- I. Use of Sharks in Comparative Neuropsychology.- A. Phylogenetic Advantages.- B. Neuroanatomical Features.- C. Behavioral Repertoire.- II. The Reign of Olfaction.- A. Origins of the "Smell Brain".- B. Multimodal Representation.- III. Telencephalic Involvement in Visual Discrimination.- A. Experimental Evidence.- B. Nature of the Deficit.- C. Performance Characteristics of Normal Sharks.- IV. References.- 3 New Observations on the Organization and Evolution of the Telencephalon of Actinopterygian Fishes.- I. Introduction.- A. The Fishes.- B. The Telencephalon.- II. Species Studied.- III. Quantitative Considerations.- IV. Normal Morphology.- A. Olfactory Bulb.- B. Area Ventralis Telencephali (V) or Subpallium.- C. Area Dorsalis Telencephali (D) or Pallium.- D. Summary and Discussion.- V. Olfactory Bulb Projections.- A. Methods.- B. Results.- C. Discussion.- VI. Histochemistry.- A. Introduction.- B. Methods.- C. Results and Discussion.- VII. General Discussion.- A. Previous Interpretations of the Telencephalon.- B. A New Hypothesis.- C. Evolutionary Considerations.- VIII. References.- 4 The Telencephalon of Teleosts.- I. Introduction.- II. Terminology.- III. Gross Anatomy and Cytoarchitecture.- IV. Olfactory Tract Projections.- V. Nonolfactory Efferent and Afferent Projections.- VI. Behavior following Ablations.- VII. Regeneration.- VIII. Conclusion.- IX. References.- 5 Projections of the Teleostean Telencephalon.- I. Introduction.- II. Commissural Fibers.- III. Projection to Pretectum and Optic Tectum.- IV. Medial Forebrain Bundle.- V. Projection to Nucleus Rotundus or Prethalamicus.- VI. Strio-lobar Bundle.- VII. Lateral Forebrain Bundle.- VIII. Projection to the Central Gray of Brain Stem.- IX. Contralateral Descending Projection.- X. Final Considerations.- XI. References.- 6 The Fish Telencephalon and Its Relation to Learning.- I. Introduction.- A. Evolutionary Considerations.- B. Anatomy.- II. Ablation of the Telencephalon.- A. General Effects.- B. Habituation.- C. Classical Conditioning.- D. Avoidance Problems.- E. Approach Problems.- III. Electrical Recording from the Telencephalon.- A. Olfaction.- B. Ascending Influences.- IV. Electrical Stimulation of the Telencephalon.- A. Effects on General Behavior and on Feeding.- B. Reinforcement Effects.- C. Effects on Other Brain Areas.- D. Effects on Learning.- V. Theories of Telencephalic Function.- A. Introduction.- B. Arousal.- C. Attention and Consolidation.- D. Secondary Reinforcement Processing.- E. Conclusions and Prospects.- VI. References.- 7 Telencephalon and Behavior in Teleost Fish: A Neuroethological Approach.- I. Introduction.- A. Ethological Introduction.- B. Neuroanatomical Introduction.- II. Methods of Studying Telencephalic Functions.- A. Ablation and Specialized Lesions.- B. Stimulation and Recording.- C. Histological Control.- III. Behavioral Changes following Ablation and Specialized Lesions of the Telencephalon.- A. Introduction.- B. Nesting Behavior.- C. Sexual and Parental Behavior.- D. Aggressive Behavior.- IV. Behavioral Observations during Stimulation of and Recording from the Telencephalon.- A. Nesting Behavior.- B. Sexual and Parental Behavior.- C. Aggressive Behavior.- D. Arousal and Reward.- V. Regenerative Aspects.- VI. Concluding Remarks.- VII. References.- 8 Organization of the Amphibian Telencephalon.- I. Introduction.- A. The Amphibia.- B. The Amphibian Telencephalon-1 On the Organization of the Telencephalon in Elasmobranchs.- I. Introduction.- II. Organization of Elasmobranchs.- III. Brain Weight-Body Weight Ratio.- IV. Telencephalic Organization in General.- V. Olfactory Input.- VI. Visual Input.- VII. Representation of Other Sensory Systems in the Telencephalon.- VIII. Telencephalic Efferent Pathways.- IX. Conclusion.- X. References.- 2 Telencephalic Function in Elasmobranchs: A Behavioral Perspective.- I. Use of Sharks in Comparative Neuropsychology.- A. Phylogenetic Advantages.- B. Neuroanatomical Features.- C. Behavioral Repertoire.- II. The Reign of Olfaction.- A. Origins of the "Smell Brain".- B. Multimodal Representation.- III. Telencephalic Involvement in Visual Discrimination.- A. Experimental Evidence.- B. Nature of the Deficit.- C. Performance Characteristics of Normal Sharks.- IV. References.- 3 New Observations on the Organization and Evolution of the Telencephalon of Actinopterygian Fishes.- I. Introduction.- A. The Fishes.- B. The Telencephalon.- II. Species Studied.- III. Quantitative Considerations.- IV. Normal Morphology.- A. Olfactory Bulb.- B. Area Ventralis Telencephali (V) or Subpallium.- C. Area Dorsalis Telencephali (D) or Pallium.- D. Summary and Discussion.- V. Olfactory Bulb Projections.- A. Methods.- B. Results.- C. Discussion.- VI. Histochemistry.- A. Introduction.- B. Methods.- C. Results and Discussion.- VII. General Discussion.- A. Previous Interpretations of the Telencephalon.- B. A New Hypothesis.- C. Evolutionary Considerations.- VIII. References.- 4 The Telencephalon of Teleosts.- I. Introduction.- II. Terminology.- III. Gross Anatomy and Cytoarchitecture.- IV. Olfactory Tract Projections.- V. Nonolfactory Efferent and Afferent Projections.- VI. Behavior following Ablations.- VII. Regeneration.- VIII. Conclusion.- IX. References.- 5 Projections of the Teleostean Telencephalon.- I. Introduction.- II. Commissural Fibers.- III. Projection to Pretectum and Optic Tectum.- IV. Medial Forebrain Bundle.- V. Projection to Nucleus Rotundus or Prethalamicus.- VI. Strio-lobar Bundle.- VII. Lateral Forebrain Bundle.- VIII. Projection to the Central Gray of Brain Stem.- IX. Contralateral Descending Projection.- X. Final Considerations.- XI. References.- 6 The Fish Telencephalon and Its Relation to Learning.- I. Introduction.- A. Evolutionary Considerations.- B. Anatomy.- II. Ablation of the Telencephalon.- A. General Effects.- B. Habituation.- C. Classical Conditioning.- D. Avoidance Problems.- E. Approach Problems.- III. Electrical Recording from the Telencephalon.- A. Olfaction.- B. Ascending Influences.- IV. Electrical Stimulation of the Telencephalon.- A. Effects on General Behavior and on Feeding.- B. Reinforcement Effects.- C. Effects on Other Brain Areas.- D. Effects on Learning.- V. Theories of Telencephalic Function.- A. Introduction.- B. Arousal.- C. Attention and Consolidation.- D. Secondary Reinforcement Processing.- E. Conclusions and Prospects.- VI. References.- 7 Telencephalon and Behavior in Teleost Fish: A Neuroethological Approach.- I. Introduction.- A. Ethological Introduction.- B. Neuroanatomical Introduction.- II. Methods of Studying Telencephalic Functions.- A. Ablation and Specialized Lesions.- B. Stimulation and Recording.- C. Histological Control.- III. Behavioral Changes following Ablation and Specialized Lesions of the Telencephalon.- A. Introduction.- B. Nesting Behavior.- C. Sexual and Parental Behavior.- D. Aggressive Behavior.- IV. Behavioral Observations during Stimulation of and Recording from the Telencephalon.- A. Nesting Behavior.- B. Sexual and Parental Behavior.- C. Aggressive Behavior.- D. Arousal and Reward.- V. Regenerative Aspects.- VI. Concluding Remarks.- VII. References.- 8 Organization of the Amphibian Telencephalon.- I. Introduction.- A. The Amphibia.- B. The Amphibian Telencephalon-Primitive or Degenerate?.- II. Species Studied.- III. Normal Morphology.- A. Olfactory Bulbs.- B. Pallium.- C. Subpallium.- IV. Organization of the Olfactory System.- A. Olfactory Organs.- B. Olfactory Projections.- C. Olfactory Mediated Behaviors.- V. Ascending Telencephalic Afferents.- A. Anterograde Degeneration Studies: Regional Sources of Telencephalic Afferents.- B. Cellular Sources of Telencephalic Afferents: The Horseradish Peroxidase Method.- C. Ultrastructure of the Ascending Afferents.- D. Other Ascending Afferents: A Quintofrontal Tract in Amphibians?.- E. Functional Significance of Telencephalic Afferents.- VI. Some Intratelencephalic Connections in Amphibians.- A. Projections of the Pallium.- B. Projections of the Subpallium.- VII. Telencephalic Efferents.- VIII. Amphibian Telencephalic Organization.- A. Telencephalic Organizational Pattern.- B. Comparisons with Other Vertebrates.- IX. References.- 9 The Telencephalon of Snakes.- I. Introduction.- II. Normal Anatomy.- A. Gross Appearance.- B. Lateral Ventricle.- C. Main Olfactory Bulb.- D. Main Olfactory Tract.- E. Accessory Olfactory Bulb.- F. Accessory Olfactory Tract.- G. Retrobulbar Region.- H. Septum.- I. Cortical Mantle.- J. Dorsal Ventricular Ridge.- K. Paleostriatum.- L. Archistriatum or Amygdala.- M. Preoptic Area.- III. Fiber Connections.- A. Main Olfactory Bulb.- B. Accessory Olfactory Bulb.- C. Nucleus Sphericus.- D. Medial Cortex.- E. Dorsal Cortex.- F. Lateral Cortex.- G. Septum.- IV. Concluding Remarks.- V. References.- 10 Cytoarchitectonic and Connectional Organization of the Lacertilian Telencephalon with Comments on Vertebrate Forebrain Evolution.- I. Introduction.- II. Anatomy of the Lacertilian Forebrain.- III. Connections of the Lacertilian Forebrain.- A. Ascending Sensory Projections.- B. Intrahemispheric Corticocortical Projections.- C. Interhemispheric Corticocortical Connections.- D. Descending Telencephalic Projections.- IV. Forebrain Organization in Other Reptiles and Birds.- A. Cortex.- B. Dorsal Ventricular Ridge.- V. Telencephalic Connections in Iguana and Gekko.- A. Ascending Projections.- B. Cortical Efferent Projections.- VI. Discussion.- A. Dorsal Ventricular Ridge.- B. Dorsal Cortex.- C. Trends in Forebrain Evolution.- VII. References.- 11 Parallels in the Organization of Auditory and Visual Systems in Crocodiles.- I. Introduction.- II. Parallels in the Organization of Midbrain Auditory and Visual Areas in Caiman.- III. Parallels in the Organization of Thalamic Auditory and Visual Regions in Caiman.- IV. Other Parallels in the Organization of Auditory and Visual Systems That Synapse in the Midbrain of Caiman.- V. Comparison with Other Reptiles and Birds.- VI. Comparison with Mammals.- VII. Summary.- VIII. References.- 12 Behavioral Studies of Telencephalic Function in Reptiles.- I. Introduction.- II. Subpallium.- A. Introduction.- B. Terminology.- C. Lesion Studies of Subpallial Function: 1823 to 1967.- D. Lesion Studies of Subpallial Function: 1968 to the Present.- E. Stimulation Studies of Subpallial Function.- F. Summary.- III. Pallium.- A. Introduction.- B. Stimulation Studies.- C. Ablation Studies.- IV. Discussion.- A. Telencephalon as an Arousal System.- B. Visual Telencephalon.- C. Function of Dorsal Cortex.- V. References.- 13 Functional Organization of the Avian Telencephalon.- I. Introduction.- II. Development and Organization.- III. Bilateral Hemispherectomy.- IV. Lesions of the Tectofugal Visual Pathway.- V. Thalamofugal Visual Pathway and Wulst.- VI. Combined Lesions of Tectofugal and Thalamofugal Visual Structures.- VII. Wulst Lesions and Reversal Learning.- VIII. Extensive Hyperstriatal Lesions.- IX. Interhemispheric Relations.- X. Archistriatum and Agonistic Behavior.- XI. Nucleus Basalis and Feeding Behavior.- XII. Central Control of Birdsong.- XIII. Summary and Conclusions.- XIV. References.- 14 Morphological Correlates of Specialized Elaborations in Somatic Sensory Cerebral Neocorte.- I. Introduction.- II. Gyral Configuration in Somatic Sensory Cerebral Cortex Related to Behavioral Specialization.- A. Proposed from Procyonids.- B. Tested in Marsupial Wombats.- III. Subcortical Correlates of Gyral Formations: Lobules.- A. Ventrobasal (Somatic Sensory) Nucleus of Thalamus.- B. Cuneate-Gracile Nuclear Complex of the Medulla.- C. What Are Lobules?.- IV. Role of Receptors in the Development of Lobules.- A. Relation of Receptor Density to Presence and Volume of Lobules.- B. Absence of Cuneate-Gracile Lobules following Early Receptor Removal.- V. Intracortical Correlates of Sensory Specialization: Barrels and Cellular Condensations.- A. Barrels in Layer IV of Sensory Neocortex.- B. Role of Receptors in the Development of Barrels.- C. Regions of Cellular Condensation and Rarefaction Related to Sensory Maps in Layer IV of Sensory Neocortex.- VI. Possible Relation of Barrels and Other Regions of Cellular Condensation to Gyral Formations.- VII. Summary.- VIII. References.- 15 Thalamocortical Relationships in Echidna (Tachyglossus aculeatus).- I. Introduction.- II. Materials and Methods.- A. Subjects.- B. Surgical Procedures.- C. Histological Preparation.- D. Identification of Cortical Lesions and Thalamic Degeneration.- III. Results.- A. Cortical Organization.- B. Thalamic Nuclear Organization.- C. Thalamocortical Relationships.- D. Unaffected Thalamic Nuclei.- E. Three-Dimensional Organization of Echidna Thalamus.- IV. Discussion.- A. Variations in Thalamocortical Circuit Connections among Vertebrates: The Search for Homologies.- B. Theoretical Concepts.- V. References.- 16 A Comparative Survey of Visual Cortex Organization in Mammals.- I. Introduction.- II. Survey of Extant Mammals.- A. Monotremes.- B. Marsupials.- C. Edentates.- D. Lagomorphs and Elephant Shrews.- E. Insectivores.- F. Archonta.- G. Carnivores.- H. Ungulates.- I. Rodents.- III. Conclusions.- IV. References.