Anatomy of the brain and spinal cord, with special reference to mechanism and function, for students and practitioners

Front matter

COLUMBIA LIBRARIES OFFSITE

HEALTH SCIENCES STANDARD

CoUese of ^f^^fiitims ant S>urgeonfii l^ihratp

Preface

The author hopes that the present edition of this work may receive from his colleagues the same generous consideration accorded to the former editions. His endeavor has been to set forth the present status of the anatomy of the human brain. and spinal cord. To do this the facts have been gleaned from many sources; and, so far as was possible, from the original sources. Being designed for a text-book, the subject-matter is presented in the order found convenient to the dissector. The description proceeds from the gross structures to the constituent neurones in each successive region. Wherever the embryology will assist the student to comprehend the adult forms, the development is briefly given in the text ; but a special chapter is also devoted to embryology, which presents a concise and connected statement of the development of the entire brain and spinal cord.

The special objects held in view throughout the book are the location of functional centers and the tracing of their afferent, associative and efferent connections. Particular emphasis is laid upon the origin, course, termination and function of conduction paths as they are met in the regular study, and the more important and better known of these paths are summed up in a final chapter on the tracing of impulses. Function is ever}^where correlated with structure; and so far as present knowledge permits, the function of each group of neurones is given in connection with its anatomical description.

The BNA Nomenclature is followed almost without exception, the English equivalents of the Latin terms being very largely employed.

Keeping pace with the lectures, every student is expected to dissect the human brain in the laboratory, exposing, studying and sketching every macroscopic structure as it occurs in the work;

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VI PREFACE.-

and, then with the microscope, examine the minute structure and picture the histology of the same parts. For these purposes the class should be taken in small sections, divided into groups of two to four students, and each group should be provided with a well hardened human brain. It is desirable that each student should receive a well stained microscopic section of every important part. This is, however, often impossible; and the instructor may get along with considerable satisfaction, by having the students exchange, if he has but a few sets of slides.

The author wishes to acknowledge his indebtedness to recent literature and to standard works on anatomy. McMurrich's "Development of The Human Body," Barker's "BNA" and Barker's " Nervous System," the work of Dr. Alfred W. Campbell, " Histological Studies on the Localization of Cerebral Function," the "Text-book of Anatomy" and "Memoirs " of D. J. Cunningham, F. R. S., and the fourth edition of Morris's " Human Anatomy" have been especially useful.

I desire to express my appreciation of the kindly assistance of my colleague, Prof. Wm. T. Eckley, M. D.; and to say that the artistic merit of the new illustrations in this book belongs to my friend and pupil, Mr. Zan D. Klopper, of Chicago, who sketched the original dramngs from my own specimens. My thanks are also due to the publishers of this little monograph, for many favors and courtesies shown me, particularly for allowing me to select illustrations from Gordinier, McMurrich and Morris, works published by them.

Harris E. Santee.

Chapter I. The Meninges Of The Brain

PAGE

Dura Mater of the Brain : i

Structure and relations i

Processes i

Sinuses 2-5

Arachnoid granulations (Pacchioni) 5

Arteries 6-7

Nerves 7

Contrasted with dura of spinal cord 7

Arachnoid of the Brain : 8

Structure 8

Relations, subarachnoid spaces 8-9

Vessels and nerves 9

Contrasted with arachnoid of the cord 9

Pia Mater of the Brain : 9

Structure and relations 9-10

Chorioid tela of third and fourth ventricles 10

Arteries and veins 10-13

Nerves 13

Contrasted with pia of spinal cord 13

Blood Supply of the Brain: 14-30

Carotid and vertebral arteries 14

A. Cerebral Circulation, Arteries : .''... 14-2 1

Arterial circle (Willisi) and branches 14-15

Ai. Cortical system of arteries 15-18

Anterior cerebral arter}- 16

Middle cerebral artery 16-1 7

Posterior cerebral artery 17

Chorioidal arteries, posterior and anterior 17-18

A2. Ganglionic system of arteries 18-21

vii

Vni TABLE OF CONTENTS.

PAGE

Antero-median ganglionic arteries i8

Antero-lateral ganglionic arteries i8

Postero-median ganglionic arteries 18-2.1

Postero-lateral ganglionic arteries 21

The Veins of the Cerebrum: 21-24

Internal veins of the cerebrum 21

Great vein of the cerebrum (Galeni) 2 1-22

External veins of the cerebrum 22-23

Superior 22

Medial 22-23

Inferior 23

Lymphatics of cerebrum 23-24

B. Circulation of the Rhombencephalon: 24-30

Bi. The medulla oblongata 24

B2. The pons (Varolii) 24-27

B3. The cerebellum 27-30

Superior cerebellar artery 27-28

Anterior inferior cerebellar artery 29

Posterior inferior cerebellar artery 29

Internal cerebellar veins. 29

External cerebellar veins 29-30

Superior 29

Inferior 29-30

Lymphatics of cerebellum 30

Table I. Embryologic Divisions of the Brain 3'^~33

Components of cerebrum 7,3

Components of rhombencephalon 33

Chapter II. General Consideration Of The Brain

Embryonic Brain Vesicles 34

Their cavities — the ventricles 34

Superior view 34~35

Posterior view 35~3^

Inferior view 36-41

Anterior area 36-37

Middle area 37-38

Posterior area : 38-41

TABLE OF CONTENTS. IX

PAGE

Roots of the Twelve Cerebral Nerves: 42-49

Nuclei, genetic and terminal 42

Olfactory nerves 42

Optic nerve 42

Oculo-motor nerve 42-45

Trochlear nerve 45

Trigeminal nerve 45

Abducent nerve 45

Facial nerve 45-46

Intermediate nerve 45-4°

Acustic nerve 4"

Glossopharyngeal nerve 46

Vagus nerve 46-49

Accessory nerve 49

Hypoglossal nerve 49

CHAPTER in.

THE CEREBRUM.

Subdivisions :

End-brain 5°

Inter-brain 5°

Mid-brain 5°

Section I. The Fore-brain or Prosencephalon 50-144 Exterior surface of fore-brain 5 ^~9^

Definition of fissure and sulcus 52

Subdivisions and borders 5^

Convex, medial and basal 52

Longitudinal fissure of cerebrum 52-55

Transverse fissure of cerebrum 55

Lateral fissure of cerebrum (Sylvii) 55-56

Sulcus centralis (Rolandi) 56'

Occipito-parietal sulcus 56-59

Lobes and gyri of convex surface 59-73

Frontal lobe, its gyri and sulci 59-63

Parietal lobe, its gyri and sulci 63-67

Occipital lobe, its gyri and sulci 67-69

TABLE OF CONTENTS.

PAGE

Temporal lobe, its gyri and sulci 69-7 1

Superior surface 70

External surface 7o~7 1

Island (Reili), its sulci and gyri 71-73

Frontal lobe, inferior surface 73~74

Island (Reili), inferior surface 74-77

Rhinencephalon 77-79

Olfactory lobe 77-79

Olfactory bulb 77-78

Olfactory tract and striae 78

Olfactory triangle 79

Parolfactory area (Brocae) 79

Anterior perforated substance 79

Tentorial area of basal surface 79-82

Chorioidal fissure 80

Hippocampal fissure 80

Ectorhinal sulcus , 80-81

Fissura coUateralis 81

Inferior temporal sulcus 81

Gyrus fusiformis 81

Gyrusjingualis 81

Limbic lobe, inferior part 81-82

Gyrus hippocampi and uncus 81-82

Dentate fascia 82

Hypothalamus 82-85

Pars optica hypothalami 82-84

Lamina cinerea terminalis S^

Optic chiasma, nerves and tracts 83-84

Tuber cinereum and inf undibulum 84

Hypophysis (pituitary body) 84

Pars mammillaris hypothalami 82 and 84

Corpora mammillaria 84

Fissures and sulci of medial and tentorial surface 84-98

Sulcus cinguli (calloso-marginal) 86

Subparietal sulcus 86

Callosal sulcus 86-89

Occipito-parietal sulcus 89

Calcarine fissure 89-90

Hippocampal fissure 90

TABLE OF CONTENTS. XI

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Chorioidal fissure 90

Collateral fissure 90~93

Ectorhinal sulcus 90~93

Inferior temporal sulcus 93

Gyri of medial and tentorial surface 93^98

Gyrus fornicatus 93~97

Gyrus cinguli 93^94

Gyrus hippocampi 94^97

Uncus 94-97

Lobus pyraformis 97

Limbic lobe, rhinencephalon 97

Gyrus rectus 97

Gyrus frontalis superior (g. marginalis) 97

Lobulus paracentralis 97

Praecuneus 97

Cuneus 97

Gyrus lingualis 97

Gyrus fusiformis 97

Summary of lobes of the cerebrum 98

Neopallium 98

Rhinencephalon (archipallium) 98

Corpus striatum 98

Internal capsule 99-104

Inferior lamina 99-100

Motor fibers 100

Sensory fibers 100

Superior lamina 100-104

Genu, frontal and occipital parts 103

Motor fibers 103

Common sensory fibers 103-104

Special sense fibers 104

Corpus callosum: 104-108

Upper surface 107

Gyri supracallosus and subcallosus 107

Inferior surface 107

Borders, posterior and anterior 107-108

Splenium, rostrum, genu, truncus 108

Boundaries of general cavity of fore-brain 108-109

Body of fornix 109

Xll TABLE OF CONTENTS.

PAGE

Crus f ornicis no

Columnae f ornicis no

Septum pellucidum in

Fifth ventricle 111-112

Lateral ventricle and its boundaries 11 2-1 2 7

Central part (body) 1 12-120

Corpus striatum 115-119

Lentiform nucleus 116

Nucleus caudatus 116-119

Stria terminalis 119

Thalamus 119

Chorioid plexus of lateral ventricle 120

Anterior horn of the lateral ventricle 1 20-1 23

Posterior horn 123

Inferior horn 123-127

Trigonum coUaterale 124

Hippocampus, its digitations 124

Chorioid epithelium , 124

Third Ventricle and Inter-Brain 127-144

Posterior commissure 132

Roof epithelium 132

Pineal body 132-135

Chorioid tela of third ventricle 135-136

Anterior commissure 136-139

Lamina terminalis 139

Thalamus 139-143

Extremities — anterior and posterior 140

Surfaces — medial, superior, lateral and inferior. . 140-143

Tegmental hypothalamic region 143

Nucleus hypothalamicus (Luysi) 143

Medial geniculate body 143-144

Section II. The Mid Brain (Mesencephalon): 144-164 Surfaces — superior, inferior, anterior, posterior 144-146

Bases pedunculi 147-151

Intermediate bundle 148

Temporo-pontal tract 148

Pyramidal tract 148-151

Fronto-pontal tract 15^

TABLE OF CONTENTS. XUl

PAGE

Substantia nigra 151

Tegmenta 152-163

Cerebral aqueduct (Sylvii) 152

Nuclei of oculo-motor and trochlear nerves 152-155

Mesencephalic nucleus of trigeminal nerve 155

Formatio-reticularis 155-163

Tegmental decussations 155

Tracts of fibers in the tegmentum 155-163

Medial (or posterior) longitudinal bundle 155-158

Fillet or lemniscus 159-161

Medial fillet — superior fillet 159-160

Lateral fillet 160-161

Spino-thalamic tract 161-162

Brachium conjunctivum 162

Olivary fasciculus 162

Descending root of trigeminal nerve 163

Quadrigeminal lamina 163-164

Colliculus superior 163-

Colliculus inferior 163-164

Brachium superius 164

Brachium inferius 164

Section III. Structure of the Cerebrum: 164-241 The neurone or nerve cell 167-173

Cell-body, perikaryon, or neurone center 167

Dendrites 167

Axone 168

Myelin sheath 168

Types of neurones (three) 168

Orders of neurones (ist, 2d, etc.) 168-171

Functions of neurones 171

Degeneration of neurones 1 71-172

Development of neurones 172-173

Sustentacular tissue 173

Epiblastic 1 73-1 74

Neuroglia and ependyma 173-174

Mesoblastic connective tissue 174

Cortical gray matter 174-204

XIV TABLE OF CONTENTS.

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Cortical or cerebral localization 177-183

Motor area, emissive 177

Psychic motor area lyg

Common sensory area 1 78

Psychic sensory area lyg

Acustic center i3j

Optic center j3 j

Olfactory and gustatory centers 181

Naming center 181

Centers of intonation, equilibration and orientation 181

Anterior association center, abstract conceptions 182

Posterior association center, concrete conceptions 182-183

Middle association center 183

Cell and fiber lamination 183-204

Plexiform layer 184-187

Layer of small pyramids 184 and 187

Layer of medium-sized pyramids 184 and 187

External layer of large pyramids 184 and 187-188

Layer of stellate cells 184 and 188

Internal layer of large pyramids 184 and 188-191

Layer of fusiform cells 184 and 191

Radiations of Meynert 192

Association fibers of Meynert 192

Atypical cortex: 192-204

Visual cortex 192-195

Olfactory cortex 195-204

Olfactory bulb 195-196

Uncus hippocampi 196-199

Nucleus amygdalae 199

Subiculum 199

Fascia dentata 200

Trigonum olfactorium, etc 200-203

Gyrus cinguli 203

Claustrum 204

Corpus striatum 204-208

Centrifugal fibers 207-208

Centripetal fibers 208

Thalamus 208-217

Thalamic nuclei 208-21 1

TABLE OF CONTENTS. XV

PAGE

White matter of the thalamus 211-217

Cortical fillet 216-217

Occipito-thalamic radiation (optic) 217

Temporo-thalamic radiation (acustic) 217

Red nucleus 217

Nucleus hypothalamicus 218

Metathalamus 218

Medial geniculate body 218-219

Superior colliculi of corpora quadrigemina 219-220

Inferior colliculi of corpora quadrigemina 220

Nucleus lateralis superior 220

Substantia nigra 221

Central or ventricular gray matter '. 22 1-224

Hypothalamus 221-222

Pars optica 221

Pars mammillaris 221-222

Massa intermedia (middle commissure) 222

Stratum griseum centrale of mid-brain 222-224

Oculomotor nucleus 223

Trochlear nucleus 223

Trigeminal nucleus of mid-brain 224

Projection fibers of the cerebrum 224-234

Corticifugal, or motor fibers 225-231

Intermediate tract — 225

Fronto-pontal tract 225

Tempora-pontal tract 225-226

Pyramidal tract 226-231

Head and neck fibers 227

Upper extremity fibers 228

Trunk fibers 228

Lower extremity fibers 228-231

I

Destruction of by clot, etc 2

Sensory or corticipetal fibers 231-234

Medial fillet, spino-thalamic tract and brachium con-

functivum 231

Olfactory projection fibers 232

Cortical fillet (common sensory) 232-233

Taste fibers (not located) 2^;^

XVI TABLE OF CONTENTS.

PAGE

Auditory 233

Lateral fillet and brachium inferius 233

Temporo-thalamic radiation 233

Occipito-thalamic radiation (optic) 234

Commissural fibers of cerebrum 234-236

Corpus callosum 234

Anterior commissure 234-235

Coramissura hippocampi 236

Association fibers of cerebrum 236-241

Short association fibers 236-238

Long association fibers 238-241

Cingulum of gyrus fornicatus 238

Uncinate fasciculus 240

Superior longitudinal fasciculus 240

Inferior longitudinal fasciculus 240-241

Fasciculus occipito-frontalis 241

Perpendicular fasciculus 241

Section I. The Cerebellum: 242-266 Function 242

Divisions: 242

Cerebellar hemispheres 242-243

Vermis cerebelli or worm 243

Cerebellar notches, anterior and posterior 244

Medullary Body : 244-247

Inferior medullary velum 244

Brachia conjunctiva 245

Superior medullary velum (Vieussensi) 246

Corpora restiforraia 246-247

Brachia pontis 247

Horizontal sulcus of cerebellum 247-248

Superior Surface of Cerebellum: 248-251

Sulci of upper surface 248-249

Precentral sulcus 248

Postcentral sulcus 249

TABLE OF CONTENTS. XVU

PAGE

Predeclivil sulcus 249

Postdeclivil sulcus 249

Lobes of superior surface 250-251

Lobus lingulas 250

Lobus centralis 250

Lobus culminis monticuli 250

Lobus declivis monticuli 251

Lobus folii vermis 251

Inferior Surface of Cerebellum: 251-256

Sulci of lower surface 252-253

Postnodular sulcus 252

Prepyramidal sulcus 252-253

Postpyramidal sulcus 253

Midgracile and postgracile 253

Lobes of lower surface 253-256

Lobus noduli 253-254

Lobus uvulae 254

Lobus pyramidis 254-255

Lobus tuberis 255-256

Cortical Gray Matter of the Cerebellum 256-260

Superficial layer 256-258

Stratum cinereum 256

Stratum gangliosum 257

Cells of Purkinje and stellate cells 257

Fibers of superficial layer 257-258

Deep layer (stratum granulosum) 258-260

Cells of granular layer 258-259

Fibers of granular layer 260

Function of stellate, granule and Purkinje cells 260

Neuroglia of cerebellum 260

Ganglionar Gray Matter of Cerebellum 260-262

Function, relay stations 260

Nucleus dentatus 260-261

Nn. emboliformis, globosus and fastigii 261

White Substance — Corpus Medullare: 262-266

Brachium conjunctivum 263

Superior medullary velum 263-264

Brachium pontis 264

Corpus restiforme 264-265

XVlll TABLE OF CONTENTS.

PAGE

Commissural fibers 265

Section II. The Pons (Varolh) 266-284 Superior and inferior 266

Anterior (Tuber annulare) 266-269

Posterior — ^ventricular, and attached part 269-270

Transverse fibers of the pons 271-272

Superficial of pars basilaris pontis 271

Deep transverse of pars basilaris pontis 271

Transverse of pars dorsalis pontis 271-272

Trapezoid body 272

Longitudinal fibers of the pons 272-278

Ventral 272

Medial fillet and superior fillet 273-274

Lateral fillet 272

Spino-thalamic tract 272

Ascending anterior cerebello-spinal tract 272-276

Gowers's tract 276

Olivary bundle 277

Descending root of trigeminal nerve 277

Spinal tract n. trigemini 277

Nucleus pontis 277

Stratum nucleare /. 278-284

Superior olivary nucleus 278-279

N. prasolivaris and n. semilunaris 279

Nucleus of trapezoid body 279

Nuclei of recticular formation 279-280

Ponto-spinal tracts (Collieri) 280

Nuclei of trigeminal nerve 281

Genetic (motor) 281

Terminal (sensory) 281

Nucleus of abducent nerve 281-282

Nucleus of facial nerve 282

TABLE OF CONTENTS. XIX

PAGE

Salivary nucleus 283

Vestibular nucleus of auditory 283

Lesions in pons 283