Human Neuroanatomy

James R. Augustine is Professor Emeritus in the School of Medicine at University of South Carolina, Columbia, South Carolina, USA.

Preface xiii About the companion website xv

Chapter 1 Introduction to the Nervous System 1

1.1 Neurons 1

1.2 Classification of Neurons 4

1.3 The Synapse 5

1.4 Neuroglial Cells 6

1.5 Axonal Transport 9

1.6 Degeneration and Regeneration 10

1.7 Neural Transplantation 14

Further Reading 14

Chapter 2 Development of the Nervous System 17

2.1 First Week 19

2.2 Second Week 20

2.3 Third Week 20

2.4 Fourth Week 21

2.5 Fifth Week 24

2.6 Vulnerability of the Developing Nervous System 26

2.7 Congenital Malformations of the Nervous System 27

Further Reading 29

Chapter 3 The Spinal Cord 31

3.1 Embryological Considerations 31

3.2 Gross Anatomy 34

3.3 Nuclear Groups – Gray Matter 37

3.4 Functional Classes of Neurons 39

3.5 Funiculi/Fasciculi/Tracts – White Matter 40

3.6 Spinal Reflexes 41

3.7 Spinal Meninges and Related Spaces 42

3.8 Spinal Cord Injury 43

3.9 Blood Supply to the Spinal Cord 44

Further Reading 44

Chapter 4 The Brain Stem 47

4.1 External Features 47

4.2 Cerebellum and Fourth Ventricle 50

4.3 Organization of Brain Stem Neuronal Columns 52

4.4 Internal Features 54

Further Reading 65

Chapter 5 The Forebrain 67

5.1 Telencephalon 67

5.2 Diencephalon 77

5.3 Cerebral White Matter 78

Further Reading 79

Chapter 6 Introduction to Ascending Sensory Paths 81

6.1 Receptors 81

6.2 Classification of Receptors by Modality 81

6.3 Classification of Receptors by Distribution and Function 84

6.4 Structural Classification of Receptors 84

6.5 Reflex Circuits 88

6.6 General Sensory Paths 89

6.7 Organization of General Sensory Paths 89

Further Reading 92

Chapter 7 Paths for Pain and Temperature 95

7.1 Path for Superficial Pain and Temperature from the Body 95

7.2 Path for Visceral Pain from the Body 102

7.3 The Trigeminal Nuclear Complex 107

7.4 Path for Superficial Pain and Thermal Extremes from the Head 108

7.5 Path for Thermal Discrimination from the Head 111

7.6 Somatic Afferent Components of VII, IX, and X 113

7.7 Trigeminal Neuralgia 113

7.8 Glossopharyngeal Neuralgia 114

Further Reading 114

Chapter 8 Paths for Touch, Pressure, Proprioception, and Vibration 117

8.1 Path for General Tactile Sensation from the Body 117

8.2 Path for Tactile Discrimination, Pressure, Proprioception, and Vibration from the Body 120

8.3 Path for Tactile Discrimination from the Head 130

8.4 Path for General Tactile Sensation from the Head 131

8.5 Path for Proprioception, Pressure, and Vibration from the Head 133

8.6 Trigeminal Motor Component 135

8.7 Certain Trigeminal Reflexes 136

Further Reading 138

Chapter 9 The Reticular Formation 141

9.1 Structural Aspects 141

9.2 Ascending Reticular System 146

9.3 Descending Reticular System 149

9.4 Functional Aspects of the Reticular Formation 149

Further Reading 153

Chapter 10 The Auditory System 155

10.1 Gross Anatomy 155

10.2 The Ascending Auditory Path 158

10.3 Descending Auditory Connections 164

10.4 Injury to the Auditory Path 165

10.5 Cochlear Implants 167

10.6 Auditory Brain Stem Implants 167

Further Reading 167

Chapter 11 The Vestibular System 171

11.1 Gross Anatomy 171

11.2 The Ascending Vestibular Path 173

11.3 Other Vestibular Connections 180

11.4 The Efferent Component of the Vestibular System 182

11.5 Afferent Projections to the Vestibular Nuclei 182

11.6 Vertigo 183

Further Reading 184

Chapter 12 The Visual System 187

12.1 Retina 187

12.2 Visual Path 191

12.3 Injuries to the Visual System 200

Further Reading 204

Chapter 13 Ocular Movements and Visual Reflexes 207

13.1 Ocular Movements 207

13.2 Conjugate Ocular Movements 207

13.3 Extraocular Muscles 209

13.4 Innervation of the Extraocular Muscles 210

13.5 Anatomical Basis of Conjugate Ocular Movements 215

13.6 Medial Longitudinal Fasciculus 216

13.7 Vestibular Connections and Ocular Movements 216

13.8 Injury to the Medial Longitudinal Fasciculus 218

13.9 Vestibular Nystagmus 218

13.10 The Reticular Formation and Ocular Movements 219

13.11 Congenital Nystagmus 219

13.12 Ocular Bobbing 219

13.13 Examination of the Vestibular System 219

13.14 Visual Reflexes 221

Further Reading 225

Chapter 14 The Thalamus 227

14.1 Introduction 227

14.2 Nuclear Groups of the Thalamus 228

14.3 Injuries to the Thalamus 238

14.4 Mapping the Human Thalamus 238

14.5 Stimulation of the Human Thalamus 239

14.6 The Thalamus as a Neurosurgical Target 239

Further Reading 240

Chapter 15 Lower Motor Neurons and the Pyramidal System 243

15.1 Regions Involved in Motor Activity 243

15.2 Lower Motor Neurons 243

15.3 Pyramidal System 247

Further Reading 256

Chapter 16 The Extrapyramidal System and Cerebellum 259

16.1 Extrapyramidal System 259

16.2 Cerebellum 267

16.3 Input to the Cerebellum Through the Peduncles 271

16.4 Input to the Cerebellum 272

16.5 Cerebellar Output 273

16.6 Cerebellar Circuitry 273

16.7 Common Discharge Paths 273

16.8 Cerebellar Functions 274

16.9 Manifestations of Injuries to the Motor System 275

16.10 Decorticate Versus Decerebrate Rigidity 278

16.11 Epilogue 278

Further Reading 279

Chapter 17 The Olfactory and Gustatory Systems 283

17.1 The Olfactory System 283

17.2 The Gustatory System 290

Further Reading 295

Chapter 18 The Limbic System 299

18.1 Historical Aspects 299

18.2 Anatomy of the Limbic System 300

18.3 Cyclic Paths of the Limbic System 306

18.4 The Human Limbic System: A Case Study 306

18.5 Descending Limbic Paths 307

18.6 Functional Aspects of the Human Limbic System 307

18.7 Limbic System Disorders 308

18.8 Injuries to Limbic Constituents 309

18.9 Psychosurgery of the Limbic System 309

Further Reading 310

Chapter 19 The Hypothalamus 313

19.1 Hypothalamic Zones (Medial to Lateral) 313

19.2 Hypothalamic Regions (Anterior to Posterior) 315

19.3 Hypothalamic Nuclei 315

19.4 Fiber Connections 321

19.5 Functions of the Hypothalamus 322

Further Reading 324

Chapter 20 The Autonomic Nervous System 327

20.1 Historical Aspects 327

20.2 Structural Aspects 328

20.3 Somatic Efferents Versus Visceral Efferents 331

20.4 Visceral Afferents 331

20.5 Regulation of the Autonomic Nervous System 333

20.6 Disorders of the Autonomic Nervous System 333

Further Reading 334

Chapter 21 The Cerebral Hemispheres 337

21.1 Facts and Figures 337

21.2 Cortical Neurons 338

21.3 Cortical Layers 338

21.4 Cortical Columns (Microarchitecture) 343

21.5 Functional Aspects of the Cerebral Cortex 343

21.6 Cerebral Dominance, Lateralization, and Asymmetry 343

21.7 Frontal Lobe 343

21.8 Parietal Lobe 347

21.9 Occipital Lobe 354

21.10 Temporal Lobe 354

21.11 Insula 357

21.12 Aphasia 358

21.13 Alexia 360

21.14 Apraxia 360

21.15 Gerstmann’s Syndrome 360

21.16 Agnosia 360

21.17 Dyslexia 360

Further Reading 361

Chapter 22 Blood Supply to the Central Nervous System 365

22.1 Cerebral Circulation 365

22.2 Aortic Arch, Brachiocephalic Trunk, and Subclavian Vessels 366

22.3 Vertebral–Basilar Arterial System 366

22.4 Blood Supply to the Spinal Cord 368

22.5 Blood Supply to the Brain Stem and Cerebellum 372

22.6 Common Carotid Artery 378

22.7 Blood Supply to the Cerebral Hemispheres 379

22.8 Cerebral Arterial Circle 383

22.9 Embryological Considerations 384

22.10 Vascular Injuries 384

Further Reading 384

Chapter 23 The Meninges, Ventricular System, and Cerebrospinal Fluid 387

23.1 The Cranial Meninges and Related Spaces 387

23.2 Ventricular System 391

23.3 Cerebrospinal Fluid 393

Further Reading 394

Figure and Table References 395

Index 399