Multiple Visual Areas

In April 1979 a symposium on "Multiple Somatic Sensory Motor, Visual and Auditory Areas and Their Connectivities" was held at the FASEB meeting in Dallas, Texas under the auspices of the Committee on the Nervous System of the American Physiological Society. The papers presented at that symposium are the basis of most of the substantially augmented, updated chapters in the three volumes of Cortical Sensory Organization. Only material in chap­ ter 8 of volume 3 was not presented at that meeting. The aim of the symposium was to review the present status of the field of cortical representation in the somatosensory, visual and auditory systems. Since the early 1940s, the number of recognized cortical areas related to each of these systems has been increasing until at present the number of visually related areas exceeds a dozen. Although the number is less for the somatic and auditory systems, these also are more numerous than they were earlier and are likely to increase still further since we may expect each system to have essentially the same number of areas related to it.

1 Multiple Cortical Visual Areas: Visual Field Topography in the Cat.- 1. Introduction.- 2. Techniques.- 3. Visual Field Topography.- 3.1. Location of Cortical Visual Areas.- 3.2. Visual Field Transformations.- 3.3. Extent of Visual Field Represented.- 3.4. Areal Magnification Factor.- 4. Unexpected Findings.- 4.1. Asymmetry.- 4.2. Variability.- 4.3. Ability of Topographic Representations of the Visual Field to Define Functional Areas.- 5. Conclusion.- 6. Summary.- Acknowledgments.- References.- 2 Comparative Studies on The Visual Cortex.- 1. Introduction.- 2. Extension and Retinotopy of the Striate and Extrastriate Visual Areas in the Rat.- 3. Receptive Field Properties of Neurons in the.- Striate Cortex of the Rat.- 4. Striate-Extrastriate Corticocortical Connections.- in the Rat.- 5. Effects of Postnatal Enucleation of the Eye on the Striate-Extrastriate Connections in the Rat.- 6. Studies on the Visual Cortex of Other Rodents.- 7. Thalamic Afferents to Extrastriate Visual Areas in Rodents.- 8. Behavioral Studies on the Extrastriate Cortex of the Rat and Rabbit.- 9. Conclusions from Studies on the Rat.- 10. Cortical Connections from the Striate Cortex in the Rabbit.- 11. Cortical Connections from the Striate Cortex in the Rat.- Acknowledgments.- References.- 3 Multiple Representations of the Visual Field: Corticothalamic and Thalamic Organization in the Cat.- 1. Introduction.- 2. Retinotopic Organization in Lateral Posterior Complex.- 2.1. Projections of Area 17.- 2.2. Projections of Area 18.- 2.3. Projections of Area 19.- 2.4. Form of the Visual Field Representations.- 3. Lateral Posterior Complex Organization.- 3.1. Subdivisions Based on Connectional Patterns.- 3.2. Applications to Study of Cortical Interconnections.- 4. Interconnections of Cortex and Thalamus.- 4.1. Corticothalamic Connections.- 4.2. Thalamocortical Connections.- 5. Summary.- Acknowledgments.- References.- 4 Families of Related Cortical Areas in the Extrastriate Visual System: Summary of an Hypothesis.- 1. Multiple Ascending Channels in the Visual System.- 2. Experimental Questions and an Hypothesis about the Thalamocortical Connections.- 3. Identification of Extrageniculate Thalamic Subdivisions by Their Afferent Connections.- 4. Evidence for Systematic Groupings of Thalamic-Extrastriate Connections.- 5. Family Clusters in the Extrastriate Cortex.- Acknowledgments.- References.- 5 Cortical and Subcortical Connections of Visual Cortex in Primates.- 1. Introduction.- 2. The Principal Afferent Pathways to Cortex.- 2.1. The Geniculostriate System.- 2.2. The Tectopulvinar System.- 3. A Brief Outline of the Subdivisions of Visual Cortex in Primates.- 4. Projections of VI.- 5. Projections of VII.- 6. Projections of MT.- 7. Projections of Other Visual Areas in the OwlMonkey.- 8. Corpus Callosum Projections.- 9. Connections of Subdivisions of Visual Cortex with Subcortical Structures.- 9.1. Cortical Projections to the Lateral Geniculate Nucleus and Superior Colliculus.- 9.2. Projections to the Pulvinar Complex.- 9.3. Projections to the Pregeniculate Nucleus and the Reticular Nucleus of the Thalamus.- 9.4. Projections to the Basal Ganglia.- 9.5. Projections to the Pons.- 10. Reciprocal and Nonreciprocal Connections.- 11. Laminar Patterns of Connections.- 12. Conclusions.- Abbreviations.- References.- 6 Organization of Extrastriate Visual Areas in the Macaque Monkey.- 1. Introduction.- 2. Two-Dimensional Cortical Maps.- 3. Visual Areas of the Occipital Lobe.- 3.1. The Location of Area MT.- 3.2. Functional and Topographical Organization of MT.- 3.3. Interhemispheric Connections.- 4. Conclusion.- Acknowledgments.- References.- 7 Visual Topography and Function: Cortical Visual Areas in the Owl Monkey.- 1. Topographic Organization.- 2. Functional Correlates.- 3. Homologous Cortical Visual Areas in Other Species.- 4. Significance of Multiple Cortical Areas.- Acknowledgments.- References.- 8 Cortical Visual Areas of the Temporal Lobe: Three Areas in the Macaque.- 1. Introduction.- 2. The Middle Temporal Area (MT).- 2.1. Location and Architectonics.- 2.2. Neuronal Properties.- 2.3. Anatomical Connections.- 2.4. Behavioral Effects of Removal.- 3. Inferior Temporal Cortex (IT).- 3.1. Location and Architectonics.- 3.2. Neuronal Properties.- 3.3. Anatomical Connections.- 3.4. Behavioral Effects of Removal.- 4. Superior Temporal Polysensory Area (STP).- 4.1. Location and Architectonics.- 4.2. Neuronal Properties.- 4.3. Anatomical Connections.- 4.4. Behavioral Effects of Removal.- 5. An Hypothesis: Three Classes of Extrastriate Visual Areas.- Acknowledgments.- References.