Cerebral Cortex

1 Early Ontogenesis of the Human Cerebral Cortex.- 1. Introduction.- 2. Historical Perspectives.- 3. Origin and Early Ontogenesis of the Human Cerebral Cortex.- 3.1. Human Embryonic Stage 15 (ca. 33 Days; ca. 7-9 mm).- 3.2. Human Embryonic Stage 17 (ca. 41 Days; ca. 11-14 mm).- 3.3. Human Embryonic Stage 18 (ca. 44 Days; ca. 13-17 mm).- 3.4. Human Embryonic Stage 20 (ca. 51 Days; ca. 18-22 mm).- 3.5. Human Embryonic Stage 22 (ca. 54 Days; ca. 23-28 mm).- 4. Differentiation and Maturation of the Mammalian Cortical Plate.- 5. Conclusions.- 6. References.- 2 The Role of the Subplate in the Development of the Mammalian Telencephalon.- 1. Introduction.- 2. Development of Geniculocortical Connections.- 3. Neurogenesis of Cortical Layer 4.- 4. Cellular Organization of the White Matter during Development.- 5. The Subplate Is a Transient Synaptic Neuropil.- 6. The Subplate and Marginal Zones Contain a Transient Class of Peptide-Immunoreactive Neuron.- 7. The Role of Subplate Neurons in Cortical Development.- 8. References.- 3 The Reeler Malformation: Implications for Neocortical Histogenesis.- 1. Introduction.- 1.1. The Reeler Phenotype.- 1.2. Genetics and Comparative Teratology.- 2. Neuronal Migration.- 2.1. Patterns of Neurogenesis and Migration.- 2.2. Cellular Interactions Critical to Neuronal Migration.- 3. Neuron Position and Secondary Events of Neocortical Histogenesis.- 3.1. Axonal and Dendritic Growth in Normal Development.- 3.2. Axonal and Dendritic Growth in the Reeler Mutant.- 4. Recapitulation and Implications.- 5. References.- 4 The Development of the Hippocampal Region.- 1. Introduction.- 2. The Hippocampal Region in the Adult Brain.- 2.1. The Entorhinal Cortex.- 2.2. The Subicular Complex.- 2.3. Ammon's Horn or the Hippocampus Proper.- 2.4. The Dentate Gyrus.- 3. The Generation of Neurons in the Hippocampal Region.- 3.1. The Generation of Neurons in the Hippocampus and in the Retrohippocampal Region.- 3.2. The Generation of Neurons in the Dentate Gyrus.- 4. The Migration of the Neurons in the Hippocampal Region.- 4.1. The Migration of Neurons in Ammon's Horn and in the Retrohippocampal Region.- 4.2. The Migration of Neurons in the Dentate Gyrus.- 5. The Development of Neuronal Form in the Hippocampal Region.- 6. The Development of the Afferents to the Hippocampal Region.- 7. The Development of Efferents from the Hippocampal Region.- 8. Other Aspects of the Development of the Hippocampal Region.- 9. References.- 5 Development of Projection and Local Circuit Neurons in Neocortex.- 1. Introduction.- 2. Projection Neurons.- 2.1. Proliferation.- 2.2. Migration.- 2.3. Morphological Differentiation.- 2.4. Neurochemical Differentiation.- 3. Local Circuit Neurons.- 3.1. Proliferation.- 3.2. Migration.- 3.3. Morphological Differentiation.- 3.4. Neurochemical Differentiation.- 4. Summary and Conclusions.- 5. References.- 6 Changes in Neurotransmitters during Development.- 1. Introduction.- 2. Excitatory Amino Acids.- 3. Acetylcholine.- 4. GABA.- 5. Neuropeptides.- 5.1. Somatostatin.- 5.2. Neuropeptide Y.- 5.3. Vasoactive Intestinal Polypeptide.- 5.4. Cholecystokinin.- 6. Monoamines.- 6.1. Noradrenaline.- 6.2. 5-Hydroxytryptamine (Serotonin).- 6.3. Dopamine.- 7. References.- 7 Biochemistry of Neurotransmitters in Cortical Development.- 1. Introduction.- 2. Afferent Pathways to Cortex.- 2.1. Noradrenergic Cortical Projections.- 2.2. Dopamine Projections.- 2.3. Serotonin Innervation.- 2.4. Cholinergic Innervation.- 3. Intrinsic Cortical Neurons.- 3.1. GABA-Containing Neurons.- 3.2. Vasoactive Intestinal Peptide-Containing Neurons.- 3.3. Somatostatin Neurons.- 3.4. Cholecystokinin Neurons.- 3.5. Other Peptidergic Cortical Neurons.- 4. Glutamate Pathways.- 4.1. Excitatory Amino Acid Receptors.- 4.2. Glutamate-Stimulated PI Turnover.- 5. Conclusion.- 6. References.- 8 The Physiology of Developing Cortical Neurons.- 1. Introduction.- 2. Spontaneous Unitary Activity.- 3. Evoked Potentials in Immature Neocortex.- 3.1. Bias in Activity Revealed by Evoked Potentials.- 3.2. Laminar Development of Synaptic Activity.- 4. Postsynaptic Potentials in Immature Cortical Cells.- 4.1. Morphological and Neurochemical Substrates for EPSP and IPSP Generation.- 4.2. Postsynaptic Potentials and Field Potentials.- 5. Latencies of Evoked Neuronal Activity.- 6. Nature of Unit Responses in Immature SmI Cortex.- 6.1. Genesis of Unit Responses.- 6.2. Following Frequency.- 6.3. Response Pattern and Inhibition.- 7. Receptive Field Organization in Immature SmI Cortex.- 7.1. Kitten SmI Cortex.- 7.2. Neonatal Rat SmI Cortex.- 8. Cortical Morphology and Functional Development.- 9. Laminar Development of Visual Cortex.- 10. Receptive Field Organization in Immature Visual Cortex.- 10.1. Receptive Field Size.- 10.2. Receptive Field Structure.- 10.3. Orientation Selectivity.- 10.4. Ocular Dominance.- 11. Conclusions.- 12. References.- 9 Changes in Cytoskeletal Elements during Postnatal Development of Cerebral Cortex.- 1. Introduction.- 2. Composition of Neuronal Cytoskeleton.- 2.1. Microfilaments.- 2.2. Microtubules.- 2.3. Intermediate Filaments.- 3. Heterogeneity.- 3.1. Actin Heterogeneity.- 3.2. Tubulin Heterogeneity.- 3.3. Neurofilament Heterogeneity.- 4. Distribution.- 4.1. Distribution of Microtubules and Neurofilaments in Nervous Tissue.- 4.2. Distribution of Actin and Actin Filaments.- 5. Potential Functions of Cytoskeletal Elements in Nerve Cells.- 5.1. Role of Microtubules and Neurofilaments.- 5.2. Role of Actin.- 5.3. Role of Brain Spectrin.- 6. Cytoskeletal Changes during Postnatal Brain Development.- 6.1. Developmental Changes in Tubulin and Microtubules.- 6.2. Developmental Changes in Actin and Microfilaments.- 6.3. Developmental Changes in Neurofilament Components.- 6.4. Developmental Changes in Glial Fibrillary Acidic Protein.- 7. The Cytoskeleton and Functionally Driven Plasticity.- 7.1. The Influence of Electrical Activation on Neuronal Connectivity.- 7.2. Critical Period Plasticity.- 8. References.- 10 Development of Visual and Auditory Cortical Connections in the Cat.- 1. Introduction.- 2. Development of Cerebral Hemispheres and Commissures.- 2.1. Development of Gross Structures.- 2.2. Development of Microscopic Structures.- 3. General Considerations of Pathway Tracing Techniques in Immature Animals.- 4. Organization of Corticosubcortical Projections during Development.- 4.1. Overview.- 4.2. Development of Projections.- 5. Organization of Corticocortical Projections during Development.- 5.1. Interhemispheric Projections.- 5.2. Ipsilateral Transcortical Projections.- 5.3. Reorganization of Interhemispheric and Transcortical Projections.- 6. Synapse Formation and Receptor Appearance.- 7. Development of Functional Connections.- 7.1. Visual Cortex.- 7.2. Auditory Cortex.- 8. Experientially Induced Reorganization of Cortical Connections.- 8.1. Visual Cortex.- 8.2. Auditory Cortex.- 9. Cortical Ablation Studies.- 9.1. Anatomical Studies.- 9.2. Physiological Studies.- 9.3. Behavioral Studies.- 10. Conclusions and Speculations.- 11. References.- 11 Plasticity of Synapse Structure and Pattern in the Cerebral Cortex.- 1. Introduction.- 2. Evidence for Changes in Preexisting Synapses.- 2.1. Experience Effects on the Size of Synapses.- 2.2. Number, Density, and Location of Vesicles.- 2.3. Conformation of the Contact or Apposition Zone.- 2.4. Spine Shape Modulation.- 2.5. Subsynaptic Plate Perforations.- 3. Synaptic Number and Pattern Changes.- 3.1. Mechanisms of Experiential Modulation of Synaptogenesis in Early Development.- 3.2. Dentritic Pattern Generated by Selective Preservation and Selective Growth.- 3.3. Capacity for Synaptogenesis Continues beyond Early Development.- 3.4. Functional Roles of Changes in Synaptic Connection Patterns.- 3.5. Tests of Other Possible Causes of Synaptic Number Changes.- 3.6. Persistence of Experience-Related Synaptic Number Changes.- 4. How Do Synapse Number Changes Arise? Developmental and Mature Forms of Synaptogenesis.- 5. Other Features of Developmental Plasticity of Cerebral Cortex.- 5.1. Developmental Plasticity of Associated Tissue Elements.- 5.2. Neuromodulation of Developmental Plasticity: A Case Study.- 5.3. Multivariate Statistical Approaches to Relations among Diverse Morphological Measures.- 6. Concluding Comments.- 7. References.- 12 Effects of Nutrition on Cortical Development.- 1. Introduction.- 2. Historical Perspectives.- 3. Animal Models.- 3.1. Malnutrition or Undernutrition?.- 3.2. Timing, Duration, and Severity.- 3.3. Methodology.- 4. General Morphological Effects of Experimentally Induced Undernutrition.- 4.1. Somatic Effects.- 4.2. Brain Weights.- 5. Histological Studies on the Brains of Undernourished Animals.- 5.1. Methodological Considerations.- 5.2. Effects of Undernutrition on Cortical Structure.- 6. Undernutrition and Environment.- 6.1. Brain Weights and Cortical Thickness.- 6.2. Neuronal and Glial Cell Measurements.- 6.3. Synaptic Measurements.- 7. Concluding Remarks.- 8. References.- 13 Embryonic Vascularization of the Mammalian Cerebral Cortex.- 1. Introduction.- 2. Materials and Methods.- 3. The Endothelial Cell of CNS Growing Capillaries.- 4. CNS Capillary Angiogenesis, Anastomosis, and Lumen Formation.- 5. Embryonic Vascularization of Cerebral Cortex.- 5.1. Perineural Vascular Territory and Meningeal Compartment.- 5.2. Interneural Vascular Territory and Virchow-Robin Compartment.- 5.3. Intraneural Vascular Territory and Perivascular Glial Compartment.- 6. Conclusions.- 7. References.