The Anatomy of Manual Dexterity : The New Connectivity of the Primate Sensorimotor Thalamus and Cerebral Cortex

1 Introduction.- 1.1 Purpose and Plan of This Review.- 1.2 Primate Manual Dexterity.- 1.2.1 Using the Hand.- 1.2.2 Cerebral Cortex and Dexterity.- 1.2.3 Topography of Sensorimotor Pathways that Mediate Handling.- 1.2.4 Parallel Distributed Processing in Sensorimotor Pathways.- 2 Corticospinal Connections in the Primate.- 2.1 Introduction.- 2.2 New Methods.- 2.2.1 Mapping the Distributions of Labeled Corticospinal Neuron Somas.- 2.3 Direct Corticospinal Projections.- 2.3.1 Origins and Projections.- 2.3.2 Multiple Corticospinal Neuron Populations in the Macaque.- 2.4 Morphology of Corticospinal Neurons.- 2.4.1 Intracortical Organization of Corticospinal Neurons: Soma/Dendrite Morphology.- 2.4.2 Axon Terminations of Corticospinal Neurons.- 2.4.3 Corticomotoneurons and Manual Dexterity.- 2.5 Indirect Corticospinal Projections.- 2.5.1 Corticorubrospinal Projections.- 2.6 Spinal Circuitry Mediating Supraspinal Control of Movement.- 2.6.1 Functionally Defined Interneuron Populations: Segmental and Propriospinal Connections.- 2.7 Postnatal Maturation of Corticospinal Pathways.- 2.7.1 Maturation of Manual Dexterity in the Macaque.- 2.7.2 Maturation of Direct Corticospinal Projections in the Rodent and the Macaque.- 2.8 Comment.- 3 The Primate Sensorimotor Thalamus.- 3.1 The Thalamus and Sensorimotor Behavior.- 3.2 Architecture of the Dorsal Thalamus.- 3.2.1 Cytoarchitecture: Three-Dimensional Maps of Thalamic Nuclei.- 3.3 Functional Groupings of Nuclei Within the Sensorimotor Thalamus.- 3.3.1 Subcortical Inputs to the Sensorimotor Thalamus.- 3.4 Thalamocortical Neuron Populations of the Sensorimotor Thalamus.- 3.4.1 Thalamic Territories.- 3.5 Neuron Circuitry of Sensorimotor Thalamic Nuclei in the Macaque.- 3.5.1 Relay Neurons and Interneurons in the Sensorimotor Thalamus.- 3.5.2 Neurons of the Thalamic Reticular Nucleus.- 3.5.3 Corticothalamic Neurons.- 3.5.4 Distributions of Terminal Axons Within Thalamic Nuclei.- 3.5.5 Synaptic Organization Within Thalamic Nuclei.- 3.6 The Pulvinar, Visually Directed Hand Movements, and Object Recognition.- 3.6.1 Topography and Cytoarchitecture.- 3.7 Comment.- 4 Sensorimotor Cortex.- 4.1 Introduction.- 4.2 Distribution of Visual Information in the Parietotemporal Cortex.- 4.3 Flow of Somatosensory Information in the Parietal Cortex in the Macaque.- 4.4 Visual Space, Tangible Space, and Their Neuronal Alignment.- 4.4.1 Which Spatial Parameters Need Central Representation?.- 4.5 Connections Between Parietotemporal, Cingulate, and Prefrontal Cortex.- 4.6 Cortical Connections of Corticospinal Neuron Populations.- 5 Summary and Comments.- 6 References.- 7 Subject Index.