HX641 23529 RC341 .M56 A treatise on diseas wm Collese of l^f)v^icmn& anb burgeons! Hibrarp Digitized by the Internet Archive in 2010 with funding from Open Knowledge Commons http://www.archive.org/details/treatiseondiseasOOmett PLATE I. Opaque Optic-Nerve Fibres. — (After Beard.) — This is aeon- genital condition of the fundus oculi, in which the medullary substance of the optic-nerve fibres continues out over the retina instead of stopping at the papilla as it normally should do. In this condition and location we obtain the most direct and complete observation of the intact nervous tissue during life that it is possible to have. A TREATISE ON DISEASES OF THE NERVOUS SYSTEM BY L. HARRISON METTLER, A.M., M.D. Associate Professor of Neurology, College of Medicine of the University of Illinois; Professor of Mental and Nervous Diseases in the Chicago Clinical School; Con- sulting Neurologist to the Norwegian Deaconess' Home and Hospital, Chicago. Complete in One Volume grotusjelij %XlustvaUd CLEVELAND PRESS CHICAGO 1905 Copyright 1904 BY THE CI.EVELAXD PRESS CHICAGO PREFACE. The Neurone Doctrine is now an accepted fact. Its teachings have done more to illuminate the dark places of neurology than has any single scientific generalization heretofore promulgated. In spite of the fact that in regard to many of its details much has yet to be learned, the main principles which it lays down are universally acknowledged to be scientifically accurate and practically useful. The present treatise has been written with the view of presenting the subject of neurology in consonance with this doctrine. The diseases are classified, so far as possible, upon that basis. The neuronic structure of the nervous sys- tem is given special emphasis. A.nd the role of the neurone in the matter of the pathology and symptomatology of these diseases is kept well in view. The author feels that the time has arrived for the frank recognition of this great doctrine, not merely in histology but also in the greater field of neurology. He is convinced that one cannot acquire a proper conception of modern neurology without an adequate knowl- edge of the neuronic structure of the nervous system. Mistakes in the diagnosis and blunders in the treatment of diseases of the nervous sys- tem can be minimized only by keeping well in mind the facts taught in the neurone theory. If the present volume will enable the student and the practitioner to behold the entire field of neurology — modern neu- rology — under the brilliant illumination cast upon it by this scientific generalization, the highest wish of the author will have been attained. The unity of the nervous apparatus and its functions, the author believes, is not to-day taught as emphatically as it should be. In some quarters the tendency is marked to discuss the nervous system and its diseases in such minute detail that the universal working of the nervous system as a single, uniform, albeit compound organ, seems to have been lost sight of. This is shown particularly in connection with the subject of the cerebral localizations. Psychology is a science as well as neurology ; and as neurosis underlies psychosis, it is incumbent that a proper conception of modern psychology should be possessed to fully comprehend the nature of the cerebral localizations, the psychic symptoms of nearly all the nervous affections and the entire psychic side of neurology. The author has endeavored to make plain from the 6 PREFACE Standpoint of modern psvcholog}- many of the psycho-physical manifes- tations of the nervous organ. In the presentation of the individual diseases, their diagnosis and pathology have been especially dwelt upon, the writer being of the firm opinion that treatment and general therapeutics are absolutely valueless — sometimes positively dangerous — in the absence of a cor- rect or approximately correct diagnosis. Neurology's hardest prob- lems are in the diagnostic sphere. Given a correct diagnosis, the treat- ment is generally a very simple affair. Diagnosis and pathology rest upon anatomy and physiolog}-, hence much space has been given to normal as well as abnormal neurology in the following work. The proper classification of some nervous affections is still a mat- ter of uncertainty. One has but to recall such troubles as the myo- pathies, the periodical paralyses, Landry's paralysis, certain types of polyneuritis, exophthalmic goitre, progressive facial hemiatrophy, my- asthenia gravis. Bell's mania, disseminated sclerosis, hypertrophic pachymeningitis and many others. The author has classified them in accordance with his own view and with what he believes to be the general view among the best authorities. For valuable assistance and helpful suggestions the author feels his indebtedness to many friends and desires to avail himself of this opportunity to thank especially Dr. Walter M. Fitch for some exquisite photographic work : Dr. Charles H. Beard. Dr. Oscar Dodd and Dr. Willis O. Nance for their ophthalmological assistance: Dr. G. B. Hassin and others. Grateful acknowledgment is also extended to the various publish- ing firms who have courteously permitted the use of illustrations from works issued bv them. L. H. M. TABLE OF CONTENTS. SECTION A. IXTRODUCTTOX. Peculiarities of the Nervous System and its diseases 17 Classification of nervous diseases : 22 Etiology of the diseases of the nervous system , . . 2^ Degeneracy 29 Patholog}" of the diseases of the nervous SAStem 35 Symptomatology and Diagnosis of the diseases of the nervous sys- tem 41 Examination of the patient 42 Electro-diagnosis 64 Treatment of the diseases of the nervous system 75 SECTION B. THE XEURONIC DISEASES. The Neurone and the Neuronic structure of the nervous system . . 89 The Neurone Doctrine 89 The Neuronic Architecture of the nervous system 96 The Neuroses iot a. The cerehro-spinal neuroses 102 Hysteria 102 Psychoneuroses related to Sleep and Hysteria 138 Dreams 141 Pavor nocturnus 141 Nightmare 141 Automatism 142 Somnambulism 142 Hypnotism and hypnosis 143 Catalepsy 146 TABLE OF CONTENTS Lethargy 146 Insomnia 146 Prolonged sleep 148 Sleeping sickness. Negro lethargy 148 Vertigo 149 Ocular vertigo 1 52 Aural vertigo. Meniere's disease 153 Neurasthenia 157 Hypochondriasis 173 The Traumatic Neuroses 182 Epilepsy 188 Myoclonus-epilepsy 207 Hemicrania. Migraine 221 Headache. Cephalalgia 234 The Neuralgias 242 Tic douloureux, prosopalgia 248 Glossodynia : 250 Occipital neuralgia 250 Cervico-brachial neuralgia 251 Mastodynia 25 r Lumbar neuralgia 251 Coccydynia 25 1 Pododynia 252 Visceral neuralgia 252 Spermatic neuralgia 252 Urethrodynia 252 ficlampsia 252 ficlampsia infantum 252 ficlampsia parturientium . 254 ficlampsia ursemica 255 Tetany. Tetanilla 256 Localized myospasms 262 Localized Spasmodic Tic. Tic convulsif 264 Facial tic 265 Masticatory tic 266 Hypoglossal tic 266 Tic of the trunk and extremities 266 Respiratory tic 266 Spasmodic torticollis 267 Spasmus nutans 268 General Tic. Tic impulsif 269 "Jumpers," Miryachit, Latah 270 TABLE OF CONTEXTS t) Paramyoclonub muitipiex 27i Occupation Neuroses 272 Myotonia congenita 284 The Choreas 286 Acute Minor chorea. Sydenham's chorea 287 Symptomatic chorea 297 Chronic hereditary (Huntington's) chorea 297 Electric chorea 299 Paralysis agitans. Shaking palsy 299 b. Tlie syinpathctic neuroses. Angioiieuroses and trophoiien- roses 306 The Sympathetic Nerve ; anatomy and physiology 306 Symmetrical gangrene. Raynaud's disease 310 Erythromelalgia 314 Acroparjesthesia 316 Angioneurotic oedema 318 Chronic hereditary trophcedema 321 Intermittent articular hydrops 321 Exophthalmic goitre 322 Athyrea 334 M3"xoedema 335 Cretinism „ 337 Acromegaly 339 Gigantism 343 Adiposis dolorosa 345 Scleroderma 346 Progressive facial hemiatrophy 348 Ainhum 350 The System Diseases 350 Their nature and classification 350 Diseases of the Afferent or Sensory Systetn 367 Locomotor ataxia 367 Diseases of the Efferent or Motor System .392 Progressive muscular atrophy 392 Amyotrophic lateral sclerosis 401 Progressive bulbar paralysis 406 Progressive muscular dystrophy 409 Pseudo-hypertrophic paralysis 416 Juvenile dystrophy 418 Infantile dystrophy 418 Spastic paraplegia of adults 421 Spastic paraplegia of childhood 425 lO TABLE OF CON^TENTS Secondary spastic paralyses 426 Ophthalmoplegia , 427 A'lyasthenia gravis 429 Occupation muscular atrophy. Craft palsy . 430 Acute ascending (Landry's) paralysis 431 Periodical paralysis 43^ Diseases of the Afferent and Buffer cut Systems 437 Ataxic paraplegia 439 liereditary ataxia 444 Friedreich's disease 444 Amaurotic family idiocy 451 Multiple neuritis and neuromyelitis 454 Progressive interstitial hypertrophic neuritis 454 SECTION C. THE NON-NEURONIC DISEASES. The Nature of the non-neuronic diseases 457 Part I. Non-neuronic diseases of the Spinal Cord 459 The Spinal Cord ; its anatomy and physiology 459 Spinal localization and topography 4S5 Lumbar puncture 494 Diseases of the Spinal Column 496 Dislocations and fractures of the vertebrae 496 Caries of the vertebrse. Tubercular spondylitis \ . . .499 Tumors of the vertebra 507 Syphilitic disease of the vertebrae 509 Aneurismal erosion of the vertebras 509 Spinal hydatid disease 509 Lateral curvature of the spine 509 Arthritis deformans of the spine . . . , 510 Diseases of the Membranes of the Spinal Cord 511 Ansemia and hyperaemia 511 Inflammation of the spinal membranes. Meningitis 512 External pachymeningitis 512 Chronic cervical hypertrophic pachymeningitis 514 Acute spinal leptomeningitis 516 Syphilitic spinal meningitis. Spinal syphilis 519 Spinal meningeal hemorrhage. Hematorrhachis 524 TABLE OF CONTElv[TS II Diseases of the Spinal Cord 526 Anaemia , 527 Hypergemia , , , 527 Embolism. Thrombosis. Endarteritis 528 Spinal hemorrhage. Hematomyelia • 528 MyeHtis ,. 531 Acute anterior poliomyelitis of infants 541 Poliomyelitis of adults 552 Abscess of the cord 555 Tumors of the spinal cord 555 Cavities of the spinal cord 562 Hydromyelia 563 Syringomyelia 563 Malformations of the cord. Spina bifida 569 Caisson disease .570 Diseases of the Cauda Equina and Filiim Tenninale 573 Part II. X on-neuronic diseases of the Peripheral Nerves , 576 The Peripheral Nerves; their anatomy and physiology 576 Neuritis S^'^ Multiple neuritis , 589 Alcoholic multiple neuritis 592 Lead multiple neuritis 595 Arsenical multiple neuritis 597 Argentic multiple neuritis 59'^ Mercurial multiple neuritis 598 Diphtheritic multiple neuritis 599 Rheumatic multiple neuritis 602 Puerperal multiple neuritis 602 Beriberi or Kakke - 603 Akatama 603 Leprous multiple neuritis 60J. Tumors of the Nerves. Neuromata 600 Multiple neuromata 609 Fibroma molluscum multiplex 6og Plexiform neuroma . • 6id Diseases of the Spina! Nerves 613 Phrenic nerve 613 The brachial plexus • 614 Erb's palsy 616 Klumpke'"s palsy 616 Total plexus palsy 616 Obstetrical palsy 617 12 TABLE OF CONTENTS Posterior or long thoracic nerve .617 Circumflex nerve 618 - Musculo-cutaneous nerve 618 Suprascapular nerve 618 Musculo-spiral nerve 619 Median nerve 621 Ulnar nerve 622 The dorsal nerves 624 The lumbar plexus 62 x Obdurator nerve 626 Anterior crural nerve 626 The sacral plexus 626 Sciatic nerve. Sciatica 627 Plantar nerves 635 The muscles of the body, their functions and nerve supply 636 Diseases of the Cranial Nerves 643 Oculomotor or third nerve 646 Trochlear or fourth nerve 648 Abducens or sixth nerve 64S Trifacial or fifth nerve 649 Facial or seventh nerve 652 Auditory or eighth nerve 657 Glossopharyngeal or ninth nerve 658 Pneumogastric or tenth nerve 659 Accessorius or eleventh nerve 660 Hypoglossal or twelfth nerve 661 Part III. Non-neuronic diseases of the Brain 662 The Brain, its anatomy 662 Weight of the brain 664 Membranes of the brain 665 Embryological development 668 Lobes, convolutions, fissures, sulci 672 Cranio-cerebral topography 677 Minute structure of the brain 680 Cortex 681 Olfactory lobes 686 Corpora striata 689 Optic thalami 691 Optic tracts and retina 692 Regio subthalamica 695 Corpora quadrigemina 695 Peduncles of the brain 697 TABLE OF CONTENTS I O Cranial nerve nuclei 698 Olivary bodies 705 Cerebellum 705 Cerebellar cortex 707 Conducting tracts of the brain 710 Circulation of the brain 710 Brain physiology and cerebral localisation 714 Cortex 717 Internal capsule 736 Corpus callosum 72,6 Corpora striata 737 Optic thalami 737 Corpora quadrigemina, geniculate bodies and pulvinar 73S Red nucleus, etc 739 Corpora mamillaria 739 Hypophysis cerebri 739 Epiphysis cerebri 739 Crura cerebri 739 Pons and medulla • 740 Cerebellum 74° Olivary bodies 74i Symptoms of diseases of the brain 749 General symptoms 75^ Psychic symptoms 753 Disturbances of language 7^3 Motor symptoms 77^ Sensory symptoms 777 Olfactory symptoms 779 Optic symptoms • • • .780 Gustatory symptoms ; ^ '..■.'. .^' ... .'• 79^ Auditory symptoms 792 Diseases of the Membranes of the Brain . ........ i .......... . 793 Pachymeningitis 793 Hsematoma • ■ • ....... 1 ... j •• ■ -794 Leptomeningitis • • • •"• • ■ • • » -'^ •••i- • . • • • • -790 Acute leptomeningitis ..^u^.i^:. '■■■■•'■■ >j ■■■■•■ -79^ Epidemic cerebrospinal meningitis 808 Tuberculous meningitis 814 Chronic meningitis 820 Circulatory diseases of the Brain 821 Cerebral anaemia • °22 Cerebral hyperemia °25 1 4 TABLE OF COXreNTS Cerebral hemorrhage 828 Encephalomalacia. Embolism and thrombosis 845 Thrombosis of the intracranial veins and sinuses 850 Infantile hemiplegia §5^ Encephalitis . : 864 Acute hemorrhagic encephalitis 865 Acute suppurative encephalitis ; cerebral abscess 867 Acute delirium. Bell's mania 874 Cerebral syphilis • • ■ • 877 Dementia paralytica. General paresis 888 ^Multiple sclerosis ■■ • • 9°^ Tumor of the brain • 909 Intracranial aneurism '. 93.1. Hydrocephalus : 937 Serous meningitis 939 Acquired chronic hydrocephalus . 941 Congenital hydrocephalus 942 Diseases of the Pons Varolii and Medulla oblongata. Acute superior polioencephalitis '. .'. 951 Acute inferior polioencephalitis 952 Apoplectiform bulbar paralysis 952 Diseases of the Cerehellum .954 Malformations of the Brain 956 SECTION D. GENERAL MALADIES WITH LEADING NEUROLOGICAL SYMPTOMS. Alcoholism ; . . gcg The opium and kindred habits 063 Tetanus g5p Hydrophobia 063 Arthritis deformans 060 Other toxsemic troubles 071 SECTION A. INTRODUCTION. GENERAL CONSIDERATIONS UPON THE PECULIARITIES OF THE NERVOUS SYSTEM AND ITS DISEASES. The Nervous System is a unique and complex apparatus for the performance of unique and complex functions. Neither its anatomy nor its physiology' is like that of any other organ of the body. When rough- ly contemplated as a mass of tissue, constituting the center, as it were, of the entire organism, it has more or less of a uniformity of structure and a singleness of function. When regarded minutely in its multitu- dinous relations to all the various parts of the body, it is a very com- plex, compound organ with a large variety of functions. Nervous matter per se consists of a single element and its support- ing environment immensely multiplied. The two functions of this ele- ment are self-nutrition and the manifestation of a special form of irrita- bility. A study of nervous matter, whether found in the brain, the spinal cord or the peripheral nerves, exhausts itself when the nervous cell with its processes is analyzed. Its functions are summed up in the two words, self-nutrition and irritability. Its supporting environment of neuroglia, connective tissue and blood vessels is, strictly speaking, extra neural, or at least is not primarily involved in the manifestations of neurility. From this point of view the nervous system is a very simple affair. It is a point of view to keep always in mind, for in certain congenital diseases, inherited defects and degenerative, systemic maladies it offers the only clear explanation. It is difficult for us to keep this simple, uniform conception of the nervous apparatus clearly before the mind's eye, because we are accus- tomed to seeing its activities manifested in so many different ways. Mental, motor, sensory, trophic are the ways in which we .usually re- mark the exhibitions of nerve force. A moment's thought, however, will bring home the fact that motion, sensation, mentality, nutrition are not nervous phenomena. Motion belongs to the muscles, sensation to particular end-organs, nutrition to special embryonic cells and men- tality to the interplay of various different processes. In other words, the great variety of outward presentations of nervous activity is due not to any variety in the structures and functions of the intrinsic nervous l8 GENERAL COXSIDERATIOXS UPOX XERVOUS DISEASES elements themselves, but to the different organs and tissues of the body with which they are in intimate relationship and which they bind to- gether in perfect harmony of action. This also is a most important point of view from which to contem- plate the nen-ous system and one which emphasizes the peculiar differ- ence between it and the other organs of the body. In the localization of the lesion this point of view from which to regard the entire nerv-ous apparatus and its functions is a very important one. From these standpoints it must be obvious to the casual reader even that a thorough knowledge of the histology and physiology both of the nervous elements themselves and of the nervous elements with their various connections and end-organs must be presupposed before anv profitable advance can be made in the study of ner^'ous diseases. This, of course, is largely true of all the organs and tissues of the body, but nowhere in the whole range of medicine, except in neurology, is a perfect knowledge of normal structure, normal relationships and normal functions so absolutely necessary for the accurate appreciation of ab- normal changes and abnormal manifestations. The oft-quoted aphorism that disease is nothing but perverted physiolog}' comes more nearly to expressing the whole truth in neu- rology than in any other department of medicine. Much of the pessi- mism, lack of interest and ignorance in regard to the diseases of the nervous system spring out of unfamiliarity with the anatomy and physiolog}- of the normal nervous system. In many other diseases of the body there are new secretions formed, new sounds produced, new appearances presented that enable one to form a diagnosis along with the aid of a good memor}-. For example, an ascitic fluid, a valvular bruit, a crepitant rale, a peculiar intestinal discharge may be so remote from all normal physiological exhibitions that its existence alone will quite determine the diagnosis. These un- physiological symptoms afford to the examiner a most ready and avail- able means of diagnosing disease. On the other hand, there is not a symptom belonging to disease of the nen^ous system that is not in its last analysis a simple perversion of a physiological manifestation. Fagge was therefore right when long ago he declared that the symptoms of nervous disease were almost without exception those of perverted ner^'ous function. They reveal themselves always as an increase, a diminution or a modification of what would be a normal nervous exhibition. This is a most important fundamental fact to grasp in beginning the study of these diseases. It emphasizes the truth that a clear con- ception of the normal anatomy and physiology of the entire apparatus is an absolute prerequisite to the further comprehension of its pathology and symptomatology. Another peculiarity in regard to the nervous system is that most of its external manifestations are secondary in character and extraneu- ral. At no point except at the fundus of the eye do we at any time obtain a direct view of normal, functionating nerve tissue. Hidden behind the other organs and tissues, it reveals its own changes of activ- ity by the changes of activity in these organs and tissues. Motor, GENERAL CONSfDEKATIGNS UPON NERVOUS DISEASES I9 vasomotor, sensory and trophic disturbances may all be directly due> to nervous disturbances, but all that we can observe are the functional disturbances of muscles, blood vessels and special cutaneous end-organs and the nutritional changes in the related tissues. Occasionally we can observe changes in the optic nerve at the fundus of the eye to corre- spond with changes in the vision, but more often even visual dis- turbances occur without any discoverable alterations in the fundus. Practically all objective nervous manifestations therefore are extraneu- ral in character. We can only infer corresponding changes in the nervous matter from the changes that we see in the non-nervous. Even mental and subjective symptoms are practically non-neural in their manifestation. The changes in the mental functions are recognized only by the indi- vidual himself as being related to motion and sensation. A change of volition, for instance, is to the subject himself a conceptual change of muscular movement ; an alteration of some special or general sensa- tion is identified with the actual or conceptual alteration in the activity of some special end-organ such as the eye, ear or skin. Practically, therefore, all nervous manifestations, whether subjec- tive or objective, are secondary in character and involve extraneural tissues and organs. This is a startling and peculiar fact to remember always in con- sidering the semeiology of nervous diseases. So far as we know, irritability and self-nutrition are the only pri- mary physiological manifestations of unrelated nervous matter. When we speak of motor, sensory and trophic symptoms we refer merely to secondary, extraneural phenomena. Our analysis O'f the nervous activ- ity involves only inference and indirect reasoning. There is a third peculiarity in regard to the nervous apparatus that must be noted by one who wishes to understand its diseases. Though we often speak of it as a single apparatus, and though all its parts usu- ally functionate together in harmony, it is really a most complex and compound organ, made up of a great conglomeration of little organs or deposits of nervous matter, each having its own liftle sphere of activity and each exercising different functions according to the particu- lar end-organ with which it happens to be in connection. In the brain, in the spinal cord and in the nerves are clumps of elements which sub- serve motor, sensory and other functions, and yet lie in the closest sort of juxtaposition. Many observations in connection with the systemic diseases, with' the progressive degenerations, and with the changes that sometimes take place in widely separated but functionally similar parts of the nervous system, lead us to^ suspect that the nervous elements are not all exactly alike in structure. Whether they differ chemically, physically or func- tionally we cannot guess. That they differ at all is only a matter of inference. So far as our present means of examination lead us, we can merely say that in structure the nervous system seems to be the same everywhere, though in function it is like a multicolored kaleidoscope. No other organ in the body is thus constructed. As a consequence the localization of disease in the nervous system is a characteristic and 20 GENERAL COXSIDERATIOXS UPON NERVOUS DISEASES diagnostic feature. The same lesion in different parts creates very dif: ferent clinical pictures, and the mastery of the so-called selective action of poisons and disease processes is in part dissolved. Mewed independently, then, the nervous organism is seen to fall into a category of its own. Under the impulse of a strong ancestral and biological influence it appears in the embryo. The continuation of this same prenatal or hereditary influence, coupled later on with an environmental and postnatal force, guides and directs its further de- velopments. In structure it is made up of innumerable elements whose chief powers seem to be fimctionally those of self-nourishment and the exhibition of a high degree of irritability. Such is the nervous system apart from all its structural and func- tional cormections. It represents a mass of protoplasmic cells evolved from primitive embryonic cells and differentiated to a high degree for the performance of special purposes in the organism at large. It is always well to keep this conception of the nervous apparatus in mind, for it makes easy of comprehension some of the remarkable things that are observed in the nervous system in connection with heredity, de- generative influences, general infections and special'diseases. As a matter of fact, however, the nervous apparatus is practically never an independent and imrelated organ. We have already seen how it is so intimately associated with the other organs and tissues of the body that its own changes of action can only betray themselves by cor- responding changes of action in these other organs and tissues. So close is the connection and so mutuall}" dependent upon each other are the nervous elements and the rest of the organic tissues that the latter can even react upon the former almost as vigorously as the former can upon the latter. Nervous lesions can produce muscular atrophy ; but muscular disease often reacts in a wa}- to cause wasting of the nervous elements. Optic atrophy causes the visual organ to undergo marked changes, while permanent shutting out of light from the eye results in a wasting of the optic nerve. This phrase mens saiia in cor pore sann is expressive of the truth that even mental and physical processes are mutually interdependent. If the nerv^ous apparatus consists essentially, as I have previously indicated, of a mass of highly diff'erentiated cells, it is subject not only to the tissues and organs with which these cells are functionally con- nected, but also to the tissues and organs which surround and support them. The latter, as we know, consist of neuroglia, connective tissue, lymphatics and blood vessels. These, together with the nervous ele- ments, make up what in gross anatomy is called the nervous system. Sometimes the nerve cells are spoken of as the noble and parenchy- matous elements, while the nutritive and sustentacula r structures that surround them are referred to as the ignoble or interstitial. A large number of diseases of the nerv^ous system originate in these sustentacular tissues and secondarily damage the nervous apparatus in their way, just as diseases of the functionally related organs and tis- sues do in theirs. These diseases are literally as much extraneural as if they w^ere located in the surrounding bones or membranes. The only primary diseases of the nervous apparatus are those that originate GENERAL CONSIDERATIONS UPON NERVOUS DISEASES 21 and have their primary seat in the noble or true elements ; all others are secondary. The terms primary and secondary used to be employed in a grosser sense, the former being applied to all diseases that originated in the nervous system as distinguished from diseases that began in the bones, membranes and other coarse structures in the neighborhood. From the histopathological standpoint only the primary diseases of the nervous system are the parenchymatous diseases. The vascular and interstitial diseases are literally as much outside of the nervous apparatus as would be, for mstance, disease of the spinal, vertebral or cerebral membranes. They afifect the nervous apparatus secondarily and cause the appearance of nervous symptoms by their pressure or destructive influence upon the parenchymatous elements. Locomotor ataxia is a primary nervous disease ; cerebral syphilis of the gummatous type is not a nervous disease, but a disease of the blood vessels. The nervous changes in the latter are all secondary. For the proper appreciation of the intraneural diseases and the extraneural this conception of their primary and secondary charac- teristics should be insisted upon. Etiologically, pathologically, symp- tomatically and therapeutically there is the widest difference between the two sets of affections. The primary diseases are more subject to hereditary influences than are the secondary. They are degenerative in nature and are usually provoked by toxic, infective, cachectic, nutritional and other depressing causes of a general character. Their symptomatology is purely neu- rotic and as a rule is more or less uniform and progressive from the start. The localization symptoms are comparatively clear and well de- fined. Their prognosis is generally fan* as to life, but bad as to recov- ery. Their treatment is most discouraging. They are both organic and functional, inherited and acquired. Inherited defect is at the bottom of a good many of them and accounts largely for the unsatisfactory character of their treatment. The secondary diseases are the result of traumata and various noxious agents. Heredity plays but an insignificant role here. The primary seat of these troubles is strictly extraneural, and hence the lesions represent all sorts of general and specific vascular and connec- tive tissue changes. Inflammation is at the foundation of most of these troubles and by pressure and otherwise the inflammatory process damages the parenchy- matous elements or the true nervous apparatus. The symptomatology of these diseases bears a double countenance — namely, the symptoms of the vascular disturbance and the symptoms of the nervous. The former are varied in character, are more or less febrile and are the same wherever the lesion may be located ; the latter are more uniform, reveal progressive irritation and destruction of the neighboring nerve elements, and are varied according to the location of the lesion. As these diseases are usually diffuse, the localization of the lesion is not a prominent feature and is possible only when the lesion happens to be of a certain character. The prognosis of these diseases depends upon the extent of the 22 GENERAL CONSIDERATIONS UPON NERVOUS DISEASES damage done to the nervous elements and to some few particular in- herent features of their own. As a rule it is hopeful. Their treatment is generally effective and sometimes is rewarded with most brilliant success. They are practically all organic diseases, though the nervous elements for a time may be o^nly functionally dis- turbed. The minimum' of influential heredity amongst them accounts very largely for their more hopeful management. " As illustrative of what is meant by primary nervous diseases may be mentioned tabes, Friedreich's ataxia, primary Little's disease, some types of progressive muscular atrophy, amyotrophic lateral sclerosis, progressive bulbar paralysis and most of the so-called neuroses. Among the secondary group I would place all of the inflammations, hemorrhages, neoplasms, and vascular, connective tissue changes, whether they occur in the tissues immediately surrounding the nervous elements or in the more remote membranes, bones, etc. Myelitis, en- cephalitis and neuritis occur here. All forms of vascular diseases, such as arteritis, hemorrhage, embolism, thrombosis, must be included. Tumors are all extraneural primarily, even including the unique glio- mata. Primary sclerotic processes are extraneural, being due to con- nective tissue changes. It hardly needs to be mentioned that diseases- of the meninges and of the osseous coverings are pre-eminently extra- neural. These illustrations of wdiat is meant by primary and secondary nervous diseases do not include all of the known affections by any means. The principle underlying the distinction having once been rec- ognized, it will be an easy matter when the diseases are studied in detail to assign them respectively to one or the other class as we learn their pathology. The Classification of the diseases of the nervous system is still in a most chaotic condition. There is an obvious reason for this. Hith- erto all classifications have been based upon such varied and hetero- geneous factors as gross, arbitrary anatomical subdivisions, upoii par- ticularly prominent symptoms, or upon strange etiological and thera- peutical distinctions. Some of these classifications were so absurd that they have long passed into the limbo of oblivion. Our knowledge of the nervous system is so incomplete that we still find justification for the calling of a special symptom a disease and giving it all the dignity of a special chapter. Though we no longer head a page in our modern text- books with such meaningless terms as paralysis and apoplexy, we still treat chorea and hydrocephalus and hemicrania and headache and vertigo as though they were diseases. By the later elimination of the names Landry's Paralysis, Meniere's Disease and others and the proper assignment of these diseases to the places which their pathology indi- cates, it is seen that we are steadily though slowly progressing towards a more accurate neurological nosology. Some day symptoms will not be employed at all as the basis of classification. It was long ago recognized that the pathology of a disease should constitute the only guide for its name and classification. Pathology, however, involves both the location and the character of the lesion. Many authors adopt both factors in their classification. In one part of GENERAL CONSIDERATIONS UPON NERVOUS DISEASES 23 the book will be found the discussion of the system diseases. Here the location of the lesion is the prominent feature. In another part of the book there will be found a discussion of tumors of the nervous system and syphilis. Here obviously the character of the lesion is the principal consideration. It must be frankly admitted that in the present state of our knowledge such incongruity is not altogether blameworthy. In fact, it has its advantages for the present. Some day, however, this also will be avoidable. A very gross, yet convenient, classification, based upon location, is that which divides the diseases into those of the brain, spinal cord and peripheral nerves. Modern histology, and especially its recent magnifi- cent generalization, the Neurone Doctrine, has demonstrated that it is coarse and arbitrary to divide the nervous system intO' brain, spinal cord and nerves. It has shown us that there are no' lines of separation between these so-called parts of the nervous system. Processes from the brain cells pass far into the cord from above, while processes from the nerves extend high up into it from below. From the cord cells pass, in opposite directions, processes into the brain above and into the nerves below. In other words, most of the nervous elements lie partly in one and partly in another of these so-called divisions of the nervous system. Our ignorance of this fact has hitherto caused some most erroneous conceptions and classifications of the nervous affections and the incubus of it we even yet find hard to shake off. M^e still sometimes refer to locomotor ataxia as a spinal cord disease, though its lesion is chiefly found in nervous elements that extend farther outside of than inside of the spinal canal. There are certain bulbar diseases that present a symp- tomatology more nearly related to spinal cord than to brain phenomena. It is a question in the minds of some pathologists whether certain foirms of so-called peripheral neuritis are not really^ degenerative processes in the peripheral nerves due to trophic disturbances in the anterior horns of the cord. Certain eye symptoms have long been recognized as attrib- utable to disease in the lower part of the cervical cord. So far as the tracts and cellular processes are concerned in diseases of the nervous system, there are no demarkation lines between the brain, cord and peripheral nerves. As we will see when we come to discuss the neurone and neurone theory, the diseases that attack the true nervous elements primarily, the true nervous diseases, extend from brain into cord and into nerves and vice versa. They dO' not confine themselves to any one of these arbitrary divisions of the anatomists, but follow the course of the nervous elements. They may be classified, therefore, as Neuronic Diseases. They are the most truly nervous of all the nervous diseases. They are organic and functional, the former be- ing quite sharply localized, the latter being more difi^use and including to a large extent the so-called Neuroses and Psychoneuroses. The Neuronic Diseases and the Neuroses, therefore, will be treated of in sections by themselves and no attempt will be made to classify them as brain, cord or peripheral nerve affections. An examination of the gray matter of the nervous system reveals the fact that it is made up of a series of aggregations of cells extending all along the cerebro-spinal canal. These ganglia, or little brains, as it 24 GENERAL CONSIDERATIONS UPON NERVOUS DISEASES were, are to a certain extent independent in their individual activities and control without much interference various related organs and parts of the bodv. These ganglia are numerous and are found everywhere, though regularly situated" in all parts of the nervous system. They are in the sympathetic system, in the posterior spinal roots, and in many of the cranial nerves. They constitute the central gray matter of the cord as explained in the chapter on the minute anatomy of the cord. They are found in the nuclei, basal ganglia and cortex of the brain. Since their functions differ on account of their connection with differ- ent end-organs and different parts of the body, when they are anywhere attacked by disease, the location of the lesion can be at once determined by the peculiar symptoms presented. When the intraspinal ganglia, for instance, are affected, the symptoms are quite different from what they are when any of the intracranial ganglia are miplicated. There- fore, for obvious reasons, we still find it convenient to speak of dis- eases of the brain, of the cord, of the nerves and of the sympathetic system. In each of these divisions there are many distinct ganglionic m.asses with sharply defined functions. This enables us to carry the classifica- tion of diseases on the basis of location to a still higher point. W e subdivide those of the brain, for instance, into those of the cerebrum, the cerebellum, the pons and the medulla. We mig-ht carry the division even still farther, but as a matter of fact do not find it specially con- venient to do so. \\'e might even speak of the diseases of the motor cortex, of the visual cortex, of the sensory cortex, of the cervical cord, of the lumbar cord, etc. All this, however, can better be left to the con- sideration of the cerebral and spinal localizations in the chapters devoted to the anatomy of the brain and cord. In the following work I will adopt this provisional classification of the diseases of the nervous system, believing it to be justified by the present state of our knowledge, and realizing perfectly that newer dis- coveries will from tim.e to time transfer some of the diseases from one group into another. Neuronic Diseases. (Parenchymatous Degenerative Troubles.) a. The Functional Neuronic Diseases. 1. Cerebro-spinal. 2. Sympathetic. b. The Organic Xenronic Diseases. 1. Of the Aft'erent System. 2. Of the Eff'erent System. 3. Of Both the Aff'erent and Efferent Systems. Xon-Xeuronic Diseases. (Interstitial and Vascular troubles affecting the Neurones secondarily.) a. Of the Spinal Cord and its ^Membranes. b. Of the Peripheral Nerves. c. Of the Brain and its Membranes. General Intoxications with Special Nervous Symptoms. GENERAL CONSIDERATIONS UPON NERVOUS DISEASES GENERAL CONSIDERATIONS UPON THE ETIOLOGY OF DISEASES OF THE NERVOUS SYSTEM. It is premature to formulate an exact etiology or classification of the causes of diseases of the nervous system. They are so many, so varied and so indistinct sometimes that we are quite at a loss to give to them always their deserved valuation. For many reasons, however, an attempt should be made tO' gener- alize, so far as known data will warrant, the etiology of these affections. In the first place, the causation lying behind the pathology serves as the guide to the proper therapy. Our management of these dis- eases, even more so than in others, cannot proceed along logical and scientific lines as to the best interests of the patient until we have a clear conception of their etiology and pathology. It seems like a truism to say this and yet the pre-eminence given to therapeutics, to the neglect of etiology and pathology-, is the folly of the quack, the ignor- ance of the layman and the weakness of the physician. In the second place, we are so rapidly eliminating the innumer- able causative factors harped upon by the writers of the past, and discovering so much more positively the comparatively few real causes, that the time is getting ripe for an attempt at a systematic arrange- ment of the latter. In the third place, our knowledge of the pathology of nervous diseases has lately grown so and our conception of its relationship to all etiological antecedents has clarified to such a degree, that we are beginning to occupy a position to speak with a high tone of positive- ness of the latter as being the undeniable causes. In the fourth place, a study of the etiology of these affections points out a line for the classification of the diseases themselves, enables us to calculate the possibility of the removal of the cause and of the disease, and helps to determine the prognosis as well as the hopeful- ness or hopelessness of treatment. As all diseases of the nervous system naturally fall into one or the other of the two groups — namely, those that start primarily in the neurones and those that start primarily outside of the neurones, we must remember this in studying their etiology, for the latter is not exactly the same in all particulars for both. This will be noticed as we proceed in the discussion of the causes and especially when the particular diseases themselves are taken up for consideration. Another useful, because practical, division of the causation of nervous diseases is into those that are endogenous or developed within the body, and those that are exogenous or exert their influence from without. An ansemia is an endogenous cause of nervous degeneracy ; a blow on the head is an exogenous cause of meningitis. It would be perhaps too fine a distinction to speak of the endogen- ous and exogenous causes in relation to the neurones or true nervous elements ; and yet such a division would be both scientific and prac- tical, for all of the hereditary diseases are practically due to endogenous 26 GENERAL COXSIDERATIOXS UPOX \LRVOUS DISEASES influences within the neurones,, while all other diseases, whether merely congenital or prenatal, natal or postnatal, are exogenous. A grand starting point for the study of the etiology of nervous diseases is the division of the causes into the predisposing and the exciting. The former are inherent, of course, and include everything that involves the patient's individual body and personality. They there- fore take cognizance of his heredity, his intrauterine development, his birth and his constitutional state and his subjection to other diseases up to the moment of examination. They are concerned with his age, sex, nationality, occupation, mode of life and habits, his climatic, hygienic and social environment. The exciting causes are not neces- sarily inherent in the patient. As a matter of fact, they are more fre- quently external, all more or less temporary, and invade tfn, organism rather abruptly. They include the traumata, the intoxications and the infections. Among the reflex causes so much referred to by many writers, some are of the nature of mere predisposing factors, some fall into the category of direct traumata. I will discuss them later on. For convenience we may formulate the following scheme of the causes of the diseases of the nervous system : 1. Predisposing causes. Heredity. Age. Sex. Nationality. Occupation. Mode of Life and Habits. Climatic, Hygienic and Social Environment. 2. Exciting causes. Traumata. Intoxications. Infections. 3. Reflex causes. I will now discuss these a little more in detail and explain the omission in the schema grossly outlined above, some causes, as, for instance, tumors, parasites, etc. As has been long recognized, heredity plays its most brilliant role in connection with the nervous tissues. So recently has the nervous system, at least in its highest and most complex elaboration, been evolved in the course of biological development that we can trace an- cestral phenomena, both anatomical and functional, better in it than in any other organ or tissue of the body. Zoologists recognize this so forcibly that they are beginning to use the nervous apparatus for the basis of their higher classifications and to trace out with its aid the lines of descent in the various classes of animals. In neurology we have come to acknowledge that heredity is the most important factor biologically for modifying the nervous apparatus for good or for evil. Note carefully here the use of terms. I said the nervous apparatus. Strictly speaking, this includes, we now knovr, only the neurones and the neurosrlia. It follows logicallv and it is clearlv demonstrated em- GENERAL COXSIDERATIOXS UPON NERVOUS DISEASES 2" pirically, that in the neuronic and neuroghomatous diseases only do we find heredity exerting the most transcendent force. 2vlanv of the dis- eases of this class are purely and entirely hereditary. They are of the nature of inherited defects. Such, for example, are Friedreich's disease, some of the progressive muscular atrophies, the so-called con- genital neurasthenias, hysterias, epilepsies. There are other diseases of the neuronic class, however, that are provoked into existence by one or more exciting causes, but are local- ized and otherwise determined by the patient's heredity. In these there is a tendency toward the disease, but it remains latent until some ex- traneous cause starts the latent influence into action. It is believed that this explanation applies to many of the acquired systemic diseases like locomotor ataxia, to most of the gliomatous conditions and to a large number of the acquired and secondary neurasthenias, hysterias, epilepsies and other so-called functional neuroses. It is going too far, however, to affirm, as some have done, that a true neuronic disease cannot develop, whatever the exciting cause may be, unless there is an inherited neuropathic weakness of some sort present. It is not at all improbable that monotonous overexertion, intoxication or infection tnay expose itself in a disease of neurones that may originally haA'e been endowed with perfect health. These cases, however, are not as com- mon as is generally supposed. It is astonishing the amount of strain the perfectly healthy and well-developed nervous apparatus will bear. Most of the breakdowns that we observe in actual life, whether of the organic or functional type of neuronic disease, owe a large part of their misfortune to the inheritance of an madequate strength and vitality. In the diseases that start outside of the neurones heredity plays such a small part that it amounts to practically nothing. In certain vascular troubles, such as the cerebral hemorrhages and possibly in some of the tumors, there is a bare trace of hereditary influence. In the traumatic, toxic and infectious troubles that cause inflammation and all its sequelae, it is practically nil. The diseases that occur as the result of hereditary syphilis are not hereditary nervous diseases. Hence what I will say in regard to heredity will apply more particu- larly to the neuronic degenerations and neuroses. By direct heredity is meant the transmission of the same disease from parent to child. Such heredity is not common. -]\Iore frequently a nervous weakness or tendency is handed down. This is known as indirect heredity. When the hereditary influence is towards the pro- duction of the same disease in the child that was in the parent, it is spoken of as an inherited tendency. EA'en this is not so common. Much more frequenth' the progeny is presented with a neuropathic taint merely, which, upon provocation or without, may develop a simi- lar or dissimilar disease from that observed in the ancestry. A neu- ropathic diathesis is so frequently traceable in these cases that no ex- amination is properly conducted in which it is not promptly and most persistently inquired into. It is not always necessary that there should be a well-defined dis- ease in the parentage. Xervous strain may be sufficient to cause the 28 GKXEKAL CONSIDERA lldNS UPON NERVOUS DISEASES children to inherit a constitution that soon revels in the most elaborate forms of nervous disease. I have seen a girl go insane with a primary form of degenerative dementia for which no other possible cause could be detected than a congenital neuropathic weakness. When she was conceived and being carried her mother was under excessive worr)' and a physical and mental strain striving to make a livmg for a large and healthfully growing family. Hard brain workers, those who dis- sipate and indulge freely in alcohol and tobacco, often transmit to their children a vitiated nervous apparatus. The latter suffer from neu- rasthenia, hysteria, epilepsy and various psychoses. If both parents are- neurotic or subject themselves to causes that deteriorate the nervous system, the chances for the children are bad. The intermarriage of blood relatives is dangerous for the offspring. I have under observa- tion now a middle-aged man, the father of two vigorous, grown-up daughters, who has been the victim during the last eight years of typical disseminated sclerosis. His habits have always been exemplary and there is no known exciting cause for the disease. His paternal grandparents, however, were first cousins. His own father and a paternal uncle and aunt were all congenital deaf mutes. His own mother became a deaf mute from scarlet fever in childhood. The pa- tient himself is the younger and weaker of twins. Mental troubles not infrequently follow close blood intermarriages^ Dean concludes from his examination of i8i cases of eye troubles in an institution for the blind that of the congenital cases fourteen per cent were the result of consanguineous marriages of the first degree. He believes from his statistics that the greater the inheritability of a con- dition the more liable it is to be the result of consanguineous marriage. Sometimes the parent will be afflicted with a typical disease while the child will reveal only a general neuropathic depreciation. A mother is epileptic, her daughter becomes hysterical. It may be znce versa. A father has all his life had attacks of typical hemicrania ; his child has epileptic fits or becomes the victim of dementia prgecox. Chorea breaks out in the children of markedly neurasthenic parents. The neuroses are more frequently transmitted by the mother than by the father. The heredity has been seen to be direct, if I may say so, in alter- nate generations, indirect in succeeding -generations. Epilepsy, for instance, has been among the grandparents : genius with some of its- oddities and psychic peculiarities appeared in the next generation ; epilepsy again, with terminal insanity, reappear in the third genera- tion. This is sometimes called a manifestation of atavism, a reversal to earlier forms of nervous exhibition. Atavism is a remarkable and not such an uncommon phenomenon in the animal world. It is not frequent, however, in connection with nervous diseases. Indeed, it may seriously be questioned whether the mere repetition of the same disease back of the preceding generation is a true form of atavism. A disease in the ancestor is not necessarily an earlier or more primitive type of that seen in the progeny. It is really the same disease probably occurring in the same sort of a neu- ropathic constitution. As a phenomenon, however, this atavistic ten- dency in nervous disease, whether real or apparent, is interesting and GENERAL COXSIDERATIOXS UPOX XERVOUS DISEASES 29 ■worthy of further study. The same may be said of those diseases that :sometimes appear in collateral branches or in several members of the same family, so that they are spoken of as "familial diseases." These are largely of the nature of developmental defects or anomalies. Fried- reich's disease and some of the atrophies may be cited as illustrations. Glioma is a congenital defect. Diseases that reappear, and the morbid conditions that occur, later in life in the descendants than thev did in the ancestry, may be looked upon as waning in the family. Under the head of heredity the modern doctrines of degeneracy must receive some consideration. The term is one that is much abused and misunderstood. Degeneracy is the result of a biological taint. It is a product of liereditary and congenital influences. It is not the immediate result of environment. It therefore does not mean a falling back of the individ- ual from a previously normal state, but a falling back of the racial or familial development, as shown in the anomalous and primitive stigmata of the individual. A degenerate is what he is because of his ancestry, and not because of anything, he himself has done. It is therefore a misfortune, not a disgrace. In the physical sphere it shows itself by various stigmata, the value of which have not all been positively estab- lished. No man is perfect physically and yet we do not consider all men as degenerates. Just where degeneracy stops and so-called nor- mality begins is a hazy region ; hence the many extreme and ofttimes absurd notions put forth by those who believe and those who reject the doctrines of Lombroso. Asymmetry of the skull, protrusion of the lower teeth, irregularities about the eyes, anomalies in connection with the ears, disproportion between different parts of the face are all often signs of physical imperfection. Still greater degeneracy is seen in such conditions as hare-lip, cleft palate, irregular teeth, retinitis pig- mentosa, albinism perhaps. And yet too much must not be inferred even from such coarse defects as these. ]\Iost epileptics reveal more or less stigmata of degeneracy. Cranks and queer people very often pos- sess them. Genius has been accompanied by them. On the street scarcely an individual is seen who does not exhibit some similar phys- ical anomaly in greater or less degree. There are parallel stigmata in the neurotic and psychic manifesta- tions. They may range all the way from a slight eccentricity of thought and manner down to gross mental debility, imbecility and idiocy. As no man is perfect physically, so no man is perfect mentally. This is all too obvious when a definition of what is meant by nor- mal mentality is attempted in court during a trial for insanity. So many factors enter into the make-up of one's mental manifestations that what is craziness in one man is perfect mentality in another. The points of view vary. Hottentots are not insane, nor even degenerate, because they do not think and act as Englishmen do. A genius, an artist, may well appear to be erratic, even crazy, beside a dull financier with his one idea of money-getting. Their opinions of each other in regard to their mental exhibitions will probably be mutually uncom- plimentary. "W'e may, if we please, call the average man normal. Only in 30 GENERAL CONSIDERATIONS UPON NERVOUS DISEASES comparatively coarse defects, however, can the positively abnormal be recognized. Genius is eccentric, even crazy at times ;• so seems the dull monotony occasionally of the average man. It behooves the true scientist to be conservative in his conceptions of mental and nervous degeneracy, just as he must be conservative in deciding who are afflicted with the stigmata of physical degeneracy. Along coarse lines we can recognize both psychic and physical de- generacy. We can even note a remarkable parallelism running be- tween them. A wholesale slashing about of the doctrine as some en- thusiasts have made, attributing degeneracy to all geniuses and bril- liant intellects, and to all deviations from their preconceived notions of physical and mental perfection, will lead, in the present state of our knowdedge, like a boomerang, back to their own imperfections and de- generate reasonings. The age of the individual exercises a considerable influenct in determining the nature of the disease. This is partly on account of the differences in the patient's own organism and in his habits and en- vironment in dififerent years. It may even be entirely secondary so far as the nervous system itself is concerned, for the primary disease may entirely determine the age at which the nervous troubles appear. The nervous sequelse of scarlet fever, for instance, occur in childhood merely because scarlet fever is a childhood disease. In childhood and earlv life generally the congenital troubles that result from prenatal and natal injuries usually declare themselves. Hereditary troubles also are apt to appear early. The infectious fevers that occur in children are responsible for a large number of nervous diseases. Early malnutrition exerts its influence, as well as unwonted strains. The child's ner\^ous apparatus is, of course, a growing and immatvire one. a fact wdiich exercises some force in the determination of the kind of disease, as well as of its symptomatology and prognosis. In middle and later childhood we observe a predominance of motor troubles, such as chorea, paralysis and convulsive seizures. The ex- cessive use of the motor apparatus in learning to talk, to walk and to adjust the voung creature to his environment is possibly the cause of this. About the time of puberty the sensory and emotional disorders are in the ascendent. Under the awakening of the sexual life and all that it means lx)th in the individual's inner sensibilities and in his relation- ship to his surroundings, hysteria, neurasthenia, epilepsy, sleep troubles,, hvpochondriasis and inherited tendencies, nervous and mental, are apt to break out. From puberty on to the climacteric the nervous system is mort «>r less stationary and developed, but it is subjected to all of the strains of an active adult life. Traumatisms of all sorts now come into play. So do the intoxications and infectious diseases of adults. After the climacteric the troubles of old age, the degenerations of all the tissues, ner\'ous and vascular, are to be counted upon. Hence the senile weakness, the apoplexies, the softenings, the arteriosclerotic and atheromatous degenerations, vertigos, neuralgias and paralyses are common. GENERAL CONSIDERATIONS UPON NERVOUS DISEASES 3 1 The influence of sex is a knotty question. Women are more emo- tional than men and are undoubtedly subject to different physiological influences. But they also lead very different lives from men. The neuroses and sensory disorders predominate among- them, whereas the organic and motor affections lead among men. Just how much of this is to be attributed to their difference oi organization, and how much to their difference of mode of living, it is not easy to say. More study is needed before the influence of sex upon the development of nervous disorders can be dogmatically spoken upon. Nationality seems to have some bearing. Whether this is a racial, a biological or a mere geographical factor is not entirely known. The neuroses, for instance, are more prominent among the Jews and the Latin races of Europe. They are old races and have been historically subjected to most unhappy conditions. A degree of degeneracy there- fore may account in part at least for their proneness to the functional troubles. The organic diseases are more common in the Germanic and Anglo-Saxon peoples. Locomotor ataxia is a rarity in the Negro and the Jap. The insanities of childhood are almost considered American diseases, but they are probably due to the strenuous lives we live here. Certain immigrant races, such as the Bohemians and Poles, probably owe their susceptibility to epilepsy and other neuroses to their de- pressed conditions in life as much as to their nationality. France is the home of hysteria ; as a people the French live a comparatively sensuous, unrestrained and highly emotional existence. All occupations that are in unhygienic surroundings, that are monotonously prolonged, that necessitate irregularity of habits, that interfere with sufflcient exercise, fresh air and relaxation, that, in a word, destroy the nice balance between all the functions of the body necessary for its health, predispose towards the development of nervous troubles. Much neurasthenia is attributed to hard work, especially mental work, in these strenuous days, whereas it is not the work that is to be blamed, but the monotony of it and the one-sided development which it enforces. Hysteria is often provoked by the narrow mental lives that many women lead, as well as by their want of self-discipline. Occupations of some kinds are particularly prone to lead to nervous troubles on account of the exposure to accidents, to intoxica- tion and to infection. Bridge builders are liable to the caisson disease; saloonkeepers suffer from alcoholic degenerations ; lead workers some- times develop lead palsy; and traveling men get syphilis and develop tertiary consequences. It is said that the unmarried suffer more from nervous diseases than the married. The freer life and greater dissipation of the former may be the proper explanation for this. The whole subject of occupation, environment and the special dangers therein is a large one and can only be referred to briefly here. The influence of the mode of life that an individual lives has already been hinted at in the consideration of the age, sex, occupation and nationality. It is very great. It involves the mental as well as the physical life. Overindulgence in eating, in the use of spirituous beverages, tea, coffee, tobacco, is a prolific source of nervous trouble. 32 GENERAL CONSIDERATIONS UPON NERVOUS DISEASES Bad sleeping arrangements, bad bathing customs, bad methods in everything will surely lead to misfortune. It is astounding how some of the simplest intimations of nature are misinterpreted and unheeded by those who ought to know better. A physician, in a high degree an irritable neurasthenic, came to me and declared that he did not seem to get well, but worse, though he stimulated himself up every day with a cold plunge bath in the morning, full doses of strychnia and long, exhausting walks. I told him I was not surprised i Excessive sexual indulgence is undoubtedly a source of much nervous breakdown in both married and unmarried. Athletics and the indulgence in outdoor sports at the present time are so excessive that they become a source of danger by putting unusual strain upon the vascular system. On the mental side, sensational literature, narrow thinking and the habit of flaring up in anger at every trifle are highly conducive to the development of the neuroses, as weU as being often a symptom of them. Why is it so frequently forgotten that the mind is as much in need of proper exercise as the muscles are? The mind is a product of brain activity and the brain grows or wastes just as any other tissue of the body if it is exercised or neglected. We do not know what parts of the brain subserve particular faculties of the mind, but we do know- that as a sort of counterpart to the biceps and triceps and lumbar mus- cles of the body there is a memory and an imagination, a logical and a speech faculty. How pitifully lop-sided is that man who toils daily after business hours in the gymnasium with his dumbbells and Indian clubs in order to develop the nmscular system, but who never once thinks of exercising specifically his imagination or his memory. The dull round of his routine life does not afTord the opportunity for very wide mental development. I am convinced that one-sidedness in mental development as well as one-sidedness in physical is responsible for some of the neurasthenia and hysteria which we observe alDOut us. A volume could be written upon the influence of habits and the mode of life in the fostering of nervous affections. Climate, apart from mere racial and geographical influences, is not an important factor in the etiology of nervous .diseases. The fact that these are more common in the temperate zones is because there the strenuous life and extreme competition are found. This suggests the truth that civilization is responsible for much nervous and mental trou- ble. Neurologists and alienists would find their services at a discount among barbarous races. In the centers where civilization is burning at white heat, as it were, namely, the great cities, there the nervous trou- bles are in abundance. In fact they are on the increase. The two great- est causes of these affections were included in that happy epigram of Krafift-Ebing, "syphilization and civilization.''' We must be careful, however, not to charge civilization with what is to be blamed upon squal- or and vile conditions in some of our cities. To argue as Rousseau did that we need to return to barbarism is a bad mixing up of cause and efifect, of separate and distinct forces, that is wholly inexcusable. Civi- lization in its true sense means culture, refinement, comfort and mental GENERAL CONSIDERATIONS UPON NERVOUS DISEASES 33 elevation. Because ignorance, stupidity, greed and poverty happen to loom up where civilization is existent, it merely shows by the contrast that much good has been accomplished though much is yet to be ac- complished. Not civilization but the abuse of the opportunities offered by civilization is the cause of the apparent mcrease of nervous troubles. Among the predisposing causes of nervous affections, certain diatheses must not be overlooked, especially the gouty and rheumatic. What passes under the general name of the litha;mic condition is read- ily recognized clinically, though the nature of the defective process is not fully understood. Faulty metabolism with faulty elimination is perhaps the real difficulty. How this reacts upon the nervous system to produce functional and peripheral diseases is not clear but that it does do so is amply demonstrated both clinically and therapeutically. I come now to the exciting causes of nervous diseases, and first and foremost I place in the list the traumata. These include all kinds of physical and mental insults. A terrific blow on the head may pro- duce less serious eft'ects than a terrible fright. Bodily injuries of all sorts, especially about the head, may set up profound nervous and mental deterioration. Primarily or secondarily the delicate neurones may be disturbed. From a gross fracture of the skull, all the way to a mere concussion, may the traumata range. The former lacerates, compresses, invades with hemorrhage, inflammation and infection the cerebral tissues; the latter jars and disturbs the functions of the neurones in such a way as to give rise to neurosis. Exposure to cold and damp is of the nature of a trauma. So are sudden excitement, tmnatural coitus and many other causes given in the books. Almost any form of infection may give rise tO' disease of the nervous organism. Usually it is of the inflammatory type of disease though in some chronic infections it may be non-infllammatory and purely a neuronic degeneration. It is generally believed that not the germs themselves but their toxic products are the immediate causes of the disease process. Syphilis, both acute and chronic, acquired and inher- ited, is hig'hly blameable. Scarlet fever, measles, influenza, pertussis, erysipelas, gonorrhoea, septicaemia, pyaemia, etc., all enter into the etiol- ogy of nervous affections. Tuberculosis, near and remote abscesses and other germ troubles may provoke metastatic lesions in the nerve cen- ters. Some tumors and parasitic growths should probably be classed here, though in a way they act more as traumatic causes by compress- ing and mechanically irritating the nervous elements near which they are located. Until we know more about the pathogenesis of these neo- plasms we can only say that infection and traumatism are the imme- diate causes of the nervous disturbances when they are present. Of the intexications that provoke nervous maladies, the alcoholic far outranks all the others. Lead, arsenic, mercury, aniline, copper, carbon dioxide, tea, coffee and tobacco are a few of the intoxicants. Here should be mentioned also the drugs that are sometimes used as a habit, morphine, cocaine, chloral. Autointoxication together with malnutrition is probably the explanation of the etiological bases of the various cachexias, of ansmia, of diabetes mellitus, of nephritis and certain alimentary troubles. 34 GENERAL COXSTDERATIOXS UPOX XERVOUS DISEASES Finally, a word must be said upon the much-discussed _ reflex causes of nervous diseases. To deny all etiological influence of a re- flex character is to deny the reflex phenomenon of the normal nervous apparatus. To attribute disease in the otherwise unaffected nervous centers to a mere reflex activity, which is a normal function of a nor- mal nervous system, is illogical on the face of it. Therefore, we as- sume that a constant reflex excitement of the nervous apparatus pro- duces the manifestation of disease symptoms in only one of two condi- tions ; either as an excitant to an already abnormal and diseased nervous organism or as an excitant to an exhausted and wearied one. In the first case the reflex is not the primary cause of the dis- ease but is clearly a mere irritant to it. In the second case, it may be seriously questioned w^hether a mere state of exhaustion ever becomes transformed into a specific type of disease. Let me illustrate. There are ophthalmologists to-day who attribute epilepsy to eye-strain. Where there is epilepsy, eye-strain as well as a painful corn on the toe, a phimosis or an impacted bowel may provoke the attacks. If there is a tendency to epilepsy even, eye- strain may start the disease into activity. In all cases of epilepsy therefore the eyes should be corrected if need be, but don't charge the eyes with the central nervous trouble. When it is contended that eye- strain produces epilepsy de novo in a previously healthy nervous appa- ratus, it is incumbent upon the ophthalmologist to explain how it does it. He declares that it does it by exhausting the nervous centers. He has been betrayed clearly in his pathology by the use of the unfortu- nate word fiinctional. Epilepsy, hysteria and neurasthenia we may grant for argument's sake are all alike in being functional but their very symptomatology proves that they are not alike in their origin and physical basis wherever and whatever that may be. The eye-strain of the ophthalmologists' pathology acts always in the one way, namely, as an exhausting strain, and yet strange to say it produces a variety of distinct specific diseases of a different character in different indi- viduals. Knowledge of the pathogenesis of these various diseases is not as clear as it should be but it certainly is clear enough to reveal the illog- ical reasoning of those who attribute a series of distinct, sharply-de- fined, different aft'ections to a mere peripheral wearying reflex that is always the same in character and points to no direct connection between these various diseases or between them and itself. The causation of different distinct pathological conditions in a previously normal system by the mere constant exercise of a single and uniform reflex irritation is a step backward and brings us face to face again with a pathology that is hazy and antiquated and from which we had fondly thought mod- ern neurology- was redeemed. In my opinion, nervous diseases are not reflex diseases though they may be aroused into expression, or excited into greater activity when so aroused, by a dozen or more sources of peripheral reflex stim- ulation. GENERAL COXSIDERATIOXS UPOX XERVOUS DISEASES 6:j GEXEE_\L COXSIDERATIOXS UPOX THE PATHOLOGY OF XER\'OUS DISEASES. In order to have a clear comprehension of the pathology of the diseases of the nerv^ous system, one must keep well in mind the com- plex character of the ner^^ous tissues and their relationship to all the other tissues. Alany diseases are secondary to extraneous affections that cause pressure or by extension and metastases invade the neri'ous system. Therefore in these diseases frequently there are pathological findings of great importance in other parts of the body. For instance, intracranial embolism is usually associated with valvular heart dis- ease; tuberculous meningitis is accompanied b}^ tuberculous foci in the lungs; abscess of the brain is very largely due to suppurative otitis media ; damage to the spinal cord frequently results from caries of the spine; disease of the muscles and various end-organs in direct functional connection with the neurones not infrequently sets up de- generative changes in the latter. It is not our province to refer to all of these extraneural troubles but merely to the pathological changes which the}' and other causes set up within the nervous apparatus. It will be remembered that nervous tissue consists of two dis- tinct sets of elements, developed from dift'erent embryonic layers in the ovum. The true nervous elements are the neurones and the neuroglia cells. Though these differ in function, the former being the excitable elements while the latter are merely sustentacular or supporting, both are found only in the nervous system, and developed from the epiblast are non-vascular. The false nervous elements are the connective tissue cells, the blood vessels, the lymphatics and the epithelium lining the ventricles. The function of these is to nourish and furnish a matrix for the true nen'ous elements. They are found in other parts of the body as well as here, are mesoblastic in origin and are vascular. Pathologically then the nen^ous system is liable to two great types of change. The non-vascular elements undergo degeneration, the vas- cular elements undergo inflammation. Degeneration is the only change that tvtv occurs in the neurones. The neuroglia cells may proliferate, form tumors and then undergo degeneration. Inflammation with all its attendant conditions, hemorrhage, vas- cular obstruction, infective processes, connective-tissue and parasitic new-growths, and sclerotic changes may occur in the vascular con- nective-tissue of the nen'ous system just as they may occur in the vascular connective-tissue of other organs and parts of the body. Un- der such circumstances the true or nobler nervous elements are damaged secondarily. It is doubtful whether a simple, primary degeneration in the true nervous elements ever sets tip inflammation secondarily in tiie vascu- lar structures. I knoAv that in locomotor ataxia, a true degenerative disease, and in some degenerative forms of polyneuritis inflammation 36 nFXKRAL COXSIUKRATIOXS UPON XERVOUS DISEASES of the meninges and of the interstitial tissues is often respectively ob- served but it" is a question whether this inflammation is not due pri- marily to the same general infection or intoxication that gives rise to the degeneration. Degeneration as it is seen in the nervous system is a unique pro- cess. It gives a very characteristic appearance to the affected tissues, and its presence and progress render the symptomatology of nervous lesions clinically almost pathognomonic. Hence its appreciation is most important. As the distinctive lesion of the nervous apparatus, it is more important than the grosser lesions of vascular origin. When a nervous element undergoes degeneration it dies, wastes and dis- appears. The cell-body swells up, then becomes granular and fatty, and finally is absorbed. The process is sometimes called chromatolysis. In the early stage and temporarily, if the degeneration is not severe or complete, there may be a shriveling up of the cell-body ; its edges then become serrated, its nucleolus disappears, its nucleus shifts to one side (decentralization), the chromophyllic particles diminish in amount and closely hug the nucleus while open sp?xes appear in the substance of the cell-body ( vacuolaticn). Such cells sometimes regenerate, pass- ing through a reverse order of events. In acute and complete degeneration the neuraxones participate in the cellular destruction. The white substance of Schwann breaks up into fatty globules, the nuclei of the neurilemma proliferate, and the entire process becomes a hollow tube containing the axis-cylinder and degenerated white substance. At length the axis-cylinder breaks down ; absorption takes place, and nothing is left. Into the hollow space vacated by the process, or neuraxone, the neuroglia and connective- elements crowd and thus render the tissue firmer and denser, more vascular and less puctuated from nerv^e fibres on cross-section (scler- osis) than it was before. Degeneration may be an acute or chronic process, severe or mild, partial or complete. Most important is the fact that it may be primary or secondary. Under certain circumstances it may involve the entire neurone or only a part of it. It may spread directly from one neurone to the next one in the same nervous pathway, provided the second neu- rone is functionally subordinate to the first. This explains the morbid anatomy of the progressive system diseases. It probably never passes directly from one neurone laterally across to another lying beside it. The simultaneous degeneration of the two neurones under such circum- stances is in all probability due to the simultaneous action of the same cause. The origin of these degenerations lets a flood of light in upon the etiology of nervous diseases. The primary degenerations may be due to hereditary, congenital, toxgemic, nutritional and traumatic influ- ences. When the vitality of the neurones, transmitted from the parent to the child, is so vitiated that they cannot develop properly, function- ate normally, or resist the deleteriou.= influences of life, they are neuro- pathic and break down into the condition of disease. In this way the developmental and familial diseases are evolved. Friedreich's ataxia and the progressive atrophies furnish capital illustrations. In all prob- GENERAL CONSIDERATIONS UPON NERVOUS DISEASES 37 ability, it is only degree that distinguishes the neuroses such as epilepsy, migraine, congenital neurasthenia and hysteria from the cited ex- amples. Congenital primary degenerations are undoubtedly due sometimes to shock and malnutrition of the mother and then of the child while the latter is in the uterus. One must not confuse with these cases the infantile hemiplegias in whom secondary degenerations occur as the result of hemorrhage, inflammation and other factors. The con- genital primarv^ degenerations are non-hereditary for the}^ are intra- uterine in origin. Most of them, like most of the natal, postnatal and adult primary degenerations, are due to general or local traumatic, nu- tritional and toxjemic influences. Profound shocks, blows and concussions, without causing any discoverable lesion, are not unfrequently seen to provoke degenerative troubles, particularly of the mild type of the neuroses. Some of these even go on to severe degenerative alterations pronounced enough to be manifested in permanent paralysis. Malnutrition as a cause of degenerative trouble needs but to be mentioned. Local malnutrition occurs from vascular oibstruction by emboli, thrombi and arteritis obliterans. Many senile forms of nerv- ous degeneration are due to inefficient nutrition and metabolism. The supreme cause of the primary degenerations in adult life are the intoxications and infections. I might have said only the intox- ications, for in the infections it is tlie poisonous products of the germs and not the germis themselves that provoke the degenerative changes. Under the head of etiology in the previous chapter I have referred to the various kinds of intoxication. Just how these intoxications act upon the nervous elements is not clear. Some probably damage them directly ; others doubtless affect them, indirectly by lowering the nutritive value of the blood. Much has yet to be learned upon this question. Perhaps the greater number of nervous degenerations are sec- ondary in origin. The function of self-nutrition for the entire nervous element, seems tO' reside in the cell body. Therefore if the cell body is damaged, all parts of the neurone undergo a parallel wasting. If a part of the neurone, say a part of the neuraxone, is severed from its cell-body, all that part that has been cut off wastes away. The latter is the well-known Wallerian type of denegeration. Now the factors that may damage the cell-bodies of a mass of neurones, or lacerate and sever their processes from them, are innu- merable and as a rule belong to the diseases and lesions of the con- nective tissue, the vascular and sustentacular elements generally. It is not necessary to^ describe these in detail but it is important to note that the localization of the lesion is rendered ofttimes very definite by the limited and definite area of destruction. As these lesions impli- cate more or less transversely the nervous paths, the degeneration travels in opposite directions away from it. Remaining always in the same system wherein it started, it advances upwards in the sensory and downwards in the motor paths if the lesion is anywhere between the cerebral cortex and the posterior spinal ganglia. If the lesion be ^8 GEXKRAL (ONSIDERATIOXS UPOX XERVOUS DISEASES outside of the posterior spinal ganglia and include the paths of both the anterior and posterior roots, the degeneration will be downward in lioth the motor and sensorv fibers in the nerves beyond the seat of the lesion. There will be no degeneration on the proximal side of the lesion. * Secondary degenerations being, due to damage of the neurone bodies or severance of the neuraxones from their nutritive centers, they are confined more distinctly and prominently to the neurones imme- diately involved. The next adjoining lower or higher neurones are but slightly afifected and then only when they are functionally subor- dinate and dependent. In this respect there is a difference between the primary degener- ations due to such general influences as heredity and intoxication, and the secondary due "to separation of a neurone or part of it from its nutritive center. Though localization symptoms may appear with the primary de- generations and in some particular cases be well-defined, they will be most pronounced and therefore most valuable in the secondary degen- erations. The whole question of localizations will be discussed however elsewhere. The constant characteristic of all those lesions, whatever their original cause may have been, that eventuate in secondary degenera- tion is that they involve vascular tissues and sooner or later are ac- companied by inflammation. Perhaps the only exception to this rule, and that is more apparent than real, is the case wherein a local area of nerve substance undergoes softening from the shutting off of its blood supply by an embolus or a thrombus. In this case the degenera- tion is of the primary type, though the lesion is grossly local and vas- cular. In all other cases, vascular trouble enters into the lesion with the appearance of more or less inflammation and secondary degenera- tion. Inflammation, therefore, is a most important feature in the pathol- ogy of the nervous system. The inflammatory process itself is iden- tically the same as it is elsewhere in the body. There is the same ini- tial hypersemia, extravasation of red corpuscles, infiltration of leu- cocytes, redness, swelling, softening and oedema. All this of course damages the delicate neurones lying in the midst of it. They undergo the degenerative process which usually terminates in complete func- tional and structural annihilation. The number of neurones that may be implicated is always a varia- ble one, depending upon the virulence of the cause and the violence of the lesion. Many neurones weather the storm and regain their func- tional integrity after the inflammation subsides. As inflammation is the reaction of the organism to an irritant, whether traumatic or infective, it is really a reparative process, an effort of nature to rid herself of noxious conditions. It is therefore always regressive rather than progressive and tends to limit itself so soon as it conquers the baleful cause which brought it into existence. In the warfare which it is carrying on against the agents of harm, it causes damage itself, some of which remains as a sort of a scar long after- GENERAL CONSIDERATIONS UPON NERVOUS DISEASES 39 wards in the conditions of sclerosis, cavity-formation and atrophy. Among the last of course are to be included the secondary degenera- tions. Usually we recognize three types of inflammation in the nerv^ous system, just as we do elsewhere. They are the simple exudative, the purulent and the so-called productive or proliferative inflamrnation. The former two are acute or subacute processes and differ from each other in regard to the presence of pus. The last is a chronic process ; is characterized by little congestion and exudation but rather by the slow formation of connective tissue. The cause of all these inflammations is not the same of course, some being due to mechanical, others to chemical, and still others to bacterial factors. It is unnecessary to discuss these further here as they are not at all peculiar. Among the residua and after-effects of inflammation in the nerv- ous system there are several of great importance. The secondary de- generations I have alread}' spoken of. There is often local softening, general destruction and necrobiosis in the vicinity, with a mass of de- bris consisting of broken down nervous tissue, and blood elements. This undergoes absorption and leaves a scar or cyst in some cases. In others, especially when the inflammatory process has been chronic, sclerosis takes place. By this term is meant a hardening of the tissues from an overgrowth of the connective tissue elements and the replac- ing of the wasted true nerve cells and processes by them. The neu- roglia usually proliferates also. In sclerosis then we observe an absence or diminution of the num- ber of neurones with an increase of the neuroglia and connective tis- sue. Whether the overgrowth of the sustentacular tissue is first, caus- ing destruction of the neurones by compression, or whether the neu- rones degenerate first and the sustentacular elements proliferate to fill up the vacuity, is not alwa3's easy to determine. It is generally con- sidered, however, that the latter method occurs in the primary degen- erative diseases, whereas the former mode obtains in the inflammatory and secondary degenerations. From what has been said under the head of degeneration, it is easy to infer that when the neurone-cells are destroyed they are never regenerated. This is a fact of common observation and accounts for the perma- nency of many forms of paralysis and trophic disturbance. A neu- raxone that is destroyed may, however, completely regenerate. Just how it does so is not minutely known. All evidence seems to point out that the neurilemma and white substance of Schwann grow again in situ, but that the axis-cylinder extends forward from the proximal or cellular end into the new nervous tissue. The former reappear some- how from the local elements, whereas the latter steadih' pushes for- ward like a branch growing from the trunk of a tree. It grows of course always from the trophic center. Some recent experiments made at the University of Chicago demonstrate in the lower animals that neuraxones can thus extend 40 GENERAL COXSIDERATIONS UPON NERVOUS DISEASES across lacerations and other forms of solntion of continuity in the cen- tral nervous svstem. An interesting pathological condition which belongs solely to the nervous svstem is what is known as gliosis or glioniatosis. It is the basis of a' certain form of tumor and cavity formation. It is essen- tially a proliferation of the glia cells and neuroglia tissue. Being non- vascular and epiblastic in origin it undergoes both primary and sec- ondary degeneration. In certain slates of embryonic defectiveness, it proliferates, breaks down, is reabsorbed and leaves a cavity. Syringo- myelia is such a case in point. Sometimes with or without apparent cause, it spreads out and creates a tumor-like formation. These are the well-known gliomata of the nervous system. Finally it joins in the proliferative process of the cormective-tissue elements in the production of the scleroses of the cerebrospinal axis. In regard to the diseases of the nervous system in which no patho- logical changes can be discovered we can only argue, form hypotheses, and balance our logic. It is a time-honored custom to call such diseases functional, and to describe them as depending upon change of func- tion without change of structure. I must confess that I am incapable of comprehending such a paradoxical condition. I cannot grasp the idea that an abnormal manifestation can be the outgrowth of a normal structure. It is argued, however, that malnutrition, and possibly slight blood changes, are the cause of the functional disturbances. When pushed to the wall, those who argue thus say that they presume there may be some temporary physical or physio-chemical change in the neurones as a result of the malnutrition or reflex irritation. That, however, is included in what I conceive of as change of structure. It is too fine for our present means of detection undoubtedly but logic can penetrate often where physical means of research fail utterly. Logic seems to me to affirm beyond all question that an attribute of a thing cannot alter in the slightest degree without some alteration in the the thing itself. An attribute does not exist apart from the thing. It is but another point of view from which w.e behold that thing. A func- tion is an attribute of a functionating body. It has no more real ex- istence apart from that body than has its color, consistency or shape. Not one of the latter can vary without some variation having taken place in the body. In the same way, the function cannot change, it seems to me, without a change having taken place in the functionating substance. Of course this has no reference to what may be called sec- ondary functions or functions resulting from the action of one normal structure upon another. Psychosis is a secondary function, for it is the result of the interplay of certain elementary impulses. An abnormal psychosis may be a functional trouble with a normal physical basis. This is further discussed under hysteria. Therefore, in my opinion, there is a pathology for the so-called neuroses and functional diseases. Our knowledge of it, like our knowl- edge of a good many other things, is still wanting. In their last analysis, functional diseases are as organic as any degenerative disease but not to s'O great a degree or so grossly as in what are commonly denominated the crs'anic diseases. GENERAL CONSIDERATIONS UPON NERVOUS DISEASES 4I As a resume of the pathology of diseases of the nervous system the following schema may be useful : A. Pathological changes distinctively and primarily Neural (in- cluding the Neurones and the Neuroglia). a. Malformations ; Hereditary and Congenital Defects ; In- complete Development or Agenesis ; Defective Development or Dysgenesis. b. Degeneration, Primary and Secondary. c. Gliosis and Gliomatosis. B. Pathological changes, not distinctively nor primarily Neural (including the connective tissues, blood-vessels, Ivmphatics and epithe- lia). a. Inflammations. b. Hyperemia, Anaemia, Hemorrhage, Qidema, Arterial and Venous Diseases generally. c. Connective Tissue Sclerosis. d. Infective Processes like Tuberculosis, vSyphilis, etc. e. All Neoplasms, Tumors, Parasitic Growths, Cysts, Ab- scesses, etc. (excepting Gliomata). GENERAL CONSIDERATIONS UPON THE SYMPTOMAT- OLOGY AND DIAGNOSIS OF DISEASES OF THE NERVOUS SYSTEM AND THE EXAMINA- TION OF THE PATIENT. It will be most appropriate to discuss the general semeiology of diseases of the brain, spinal cord, nerves and sympathetic system, at the head of the sections devoted to these diseases and immediately after the consideration of the anatomy and physiology of the respective parts of the nervous system. In this chapter I will take up, merely in a gen- eral way, the symptoms that belong to the nervous system as a whole, and will attempt some practical suggestions in regard to the proper method of examining a patient. On account of the inaccessibility of the nervous apparatus to direct examination, except in the one little spot back of the eye, and on account of the multiplicity and interrelations of its functional activities, the examination of it is a supreme test of the physician's natural ingenuity, skill and knowledge. One must ap- proach it with his mind completely unbiased, alert, and flexible. New points of view must be taken when unexpected hints are thrown out by the patient or his guardians. No opinions must be formed until the examination is finished, and even then it is sometimes well to with- hold them until after two or three future examinations. Snap diagno- ses are especially dangerous in neurology. There are geniuses, ex- ceedingly rare and far between, however, who can instinctively grasp the full situation after the patient has uttered a few sentences and ex- hibited a few signs. Even they sometimes make outrageous blunders. The more experienced a man is and the more learned in regard to the 42 GENERAL CONSIDERATIONS UPON NERVOUS DISEASES nervous mechanism of course the more swiftly and accurately will he arrive at his final diagnosis. It is the safest plan for every one, how- ever, to be patient and painstaking, to omit no details and to weigh and test every phenomenon even to the point of tediousness. A mere glance at the anatomy and physiology of the nervous sys- tem demonstrates how absolutely necessary that every organ, tissue and function must be closely interrogated. In this respect a neurological examination differs pre-eminently from every other that the medical man is called upon to make. Only in cases of the greatest emergency should a hurried manner and a quick diagnosis be adopted. It is un- fortunate, though necessary of course, that such has to be done even then, for it is sometimes the cause of some very sad mistakes. When there is grave doubt, or not a reasonably clear symptomatology under these circumstances, the physician VN'ill do well to do^ nothing. Under such conditions nature is less liable to err than is human blindness. When there is no emergency or need of special haste, the phy- sician should first note carefully all of the attendant circumstances sur- rounding the patient. If he visits the latter at his home he should ob- serv'e the environment as closely as possible, for hints are sometimes thrown out in this way in regard to the mental and social status, the mode of life, the joys and the sorrows. The relatives and companions about him may be highly suggestive. Alcoholic coma might not in- appropriately be thought of in a saloon ; hystero-neurasthenia in a girl might justly be suspected if a brutal father and a termagant mother are present; trouble from, excessive mental study would hardly be ex- pected where there were no signs of a book. The patient's own attitude must be quickly remarked and the changes it undergoes during the examination. By the attitude I mean both the physical and the mental. It is wise to examine the patient alone and in the presence of oth- ers. In hysteria it is sometimes risky to remain alone in the room with the patient, but the door can be left partly open while the friends and relatives are in a distant room. The presence of one of the latter when distasteful may cause all sorts of irregularities in the symptoms. A temporary change of environment often astonishingly changes the complexion of things. I remember a woman who was sent to a pri- vate hospital several times by me. It was almost ludicrous how reg- ularly as clock-work she flew into her hysterical attacks at home while during weeks at the hospital she was as docile and reasonable as any creature. Syphilitics will often admit to the consultant, who charges them a good fee and for whom they have therefore perhaps an exag- gerated reverence, the disease that they have constantly and strenu- ously denied to their family doctor. Get the patient always, if possible, under other conditions and examine further before forming a final opinion. Avoid leading questions in eliciting the history of the case. Neu- rotics are particularly open to suggestion. I have seen diagnoses made that were really constructed on the semeiology suggested by the doc- tor and acquiesced in by the susceptible patient. This is an easy and common pitfall and should be carefully guarded ao-ainst. GEXERAL COXSIDER-\TIOXS UPOX XERVOUS DISEASES 43 . Let the patient first tell his own story, often in his own verbose ^vay, for thereby most valuable hints may be dropped and leading lines of examination suggested. After he has said all he has to say, then let the relatives and associates tell their story. Even let them give their opinions. Ee most patient with them for they are reasoning, albeit ignorant laymen; and the very picturesqueness of their descrip- tion, the energy and interest with which they tell of the patient's strange exhibitions, the biased yet unbiased attitude of mind in which they are, may go a long way tow-ard giving a complete clinical pic- ture, whereas a too close limitation to the mere scientific data may lead to some confusion. In the examination of hysterics, epileptics and the insane we have to depend very largely upon the accounts of the family and of the friends. We must, however, be always guarded against letting their views determine ours. A nice adjustment between the medical and the lay prejudices will here reveal the keen examiner and the skillful physician. During the telling of the history of the case by the relatives note the trend of their ideas and the degree of their intelligence. The pa- tient may have moved intellectually beyond their sphere, and his en- vironment being uncongenial he may act in a wa}- that seems queer to them but is not entirely illogical. This is the origin, in a large meas- ure, of the popular conception of the insanity and 'eccentricity of geniuses and of artists. After acquiring all the information he can from the patient and his friends, the physician takes up the examination himself and while allowing them to interject an occasional remark that may add new light to some things, he avoids being diverted from his owm course of proce- dure. He should have a general systematic method whereby to con- duct his examination, else he will be certain to overlook many things. Even though he may not have to go through the whole form every time before arriving at a diagnosis, it is nevertheless good to do so "because important m.atters may thus be brought out, time may really be saved in the end, and the practice of being systematic may develop a desirable facility for examining future patients. A scheme some- what like the following may be adopted, even printed out in one's case book : 44 GENERAL CONSIDERATIONS UPON NERVOUS DISEASES Xame Age Sex Nationality Occupation. Marriage Temperament Culture Date... Family History: Grandparents Parents Brothers and Sisters Other near Relatives Personal History : Habits as to Diet Habits as to Alcohol Habits as to Tobacco and Drugs . Habits as to Venery Inherited and Acquired Dis- eases : Syphilis Gonorrhoea Other Infections . . . Condition of the — Lungs Heart Arteries Alimentary Tract Genito-Urinarv Tract Traumata Deformities Pulse Temperature Respiration Urine Gait Attitude Patient's Account Trouble in Brief of Present Motor Symptoms Sensory Symptoms Reflexes Electrical Phenomena \'asomotor and Secretor\- Symp- toms Trophic Symptoms Eye and X'ision. . . Ear and Hearing. . Nose and Smell. . . Mouth and Taste. . General Remarks . Diagnosis A'oice Speech Handwriting Psychic Symptoms The diagnosis of disease of the nervous system depends upon both etiology and symptomatology. It must be made from all available phys- ical and mental data. Its end is the determination of the actual exist- ence of a nervous disease, the character of the lesion and its loca- tion. The real presence of a nervous disease is decided almost wholly by etiological factors and a few obser\^able changes like a choked disc or GENERAL CONSIDERATIONS UPON NERVOUS DISEASES 45 muscular atrophy. In other words not all motor and sensory and psvchic abnormal manifestations represent actual disease. Simulation and malingering may be present. Suggestibility may provoke mislead- ing exhibitions. Secondary irritation from extraneous conditions of all sorts, both in and out of the body, may give rise to the exaltation or suppression of nervous functions that closely imitate inherent nerve trouble. It is sometimes the hardest part of the diagnosis to determine whether there is an actual disease of the nervous system present. No fast rules can be laid down for determining this. It is all a matter of the logical ability, the shrewdness, the skill, and the knowledge of the diagnostician. When it is recognized that an actual disease of the nervous sys- tem is present, the nature of it must be decided by a careful study of both its etiology and symptomatology. The location of the lesion is inferred almost wholly from the symptoms, though the etiology helps in determining it slightly in some cases. In the preceding chapter upon pathology, I have pointed out some general facts in regard to the nature of the various lesions and how they may be inferred. Localization symptoms Avill be taken up at the head of the various sections devoted to the brain, the spinal cord and the nerves. The gait of the patient in walking is a most obvious symptom sometimes, and to one experienced in nervous troubles will alone often suggest the diagnosis. The hemiplegic, the tabetic, the victim of dis- turbed equilibrium of the cerebellar or other type, and of spastic para- plegia, can almost instantaneously be recognized. The attitude, with or without the peculiar gait, is frequently very significant. Who does not recognize the characteristic stoop and posi- tion of the hands in paralysis agitans? Even the laity notice the list- less, fixed, indifferent position of the victim of melancholia. If atti- tude were given more consideration, hysteria, neurasthenia, many forms of psychosis and not a few organic troubles would almost be suspected at once sometimes. The attitudes of disease are not infrequently path- ognomonic. While the patient is giving his account of the first appearance of his present trouble and of its course and symptoms up to the present mo- ment, note carefully the character of his voice and the mode of his speech. Does he speak loudly or softly? Is his voice rasping or smooth? Is there aphonia and does he have to whisper? Observe whether he trips in his speech or runs his words together or scans his sentences as if he Avere scanning a line of poetry. Does he omit or repeat words or introduce irrelevant words into his sentences ? Ask him to read and note if he does the same thing when reading. Aphonia, dysarthria and aphasia will all be discussed after the consideration of the physiology of the brain. They are mentioned here simply to im- press the importance of noting them carefully in the course of the ex- amination. Agraphia, trembling and other impediments to writing will also be described elsewhere. Psychic symptoms are hardly of less importance in neurology than 46 GENERAL CONSIDERATIONS UPON NERVOUS DISEASES they are in psychiatry. The niincl is the product of cerebral activity, and cerebral activity is provoked by afferent nervous impulses. It may be interesting but hardly profitable to discuss such questions as the immateriality of mind and the duality of man's nature. We have no proof, that can be called scientific, of a consciousness apart from cerebral function. To say this is not to deny the mind's possible im- material existence ; it is merely affirming the scientific limitations of the question. To escape all such gross notions as mental telepathy, mental trans- ference, mind-reading, clairvoyance, spiritism, etc., one has but ta recollect that psychic phenomena are never known to occur without simultaneous cerebral phenomena. Dead brains have never, in all the ages, given the slightest evidence of the presence of mind, and mind has never been observed apart from living brains. This interdependence is further shown in the parallelism that ob- tains between physical disease and mental aberration. In many cases- actual gross changes are observed in the brain ; in others the changes are so slight that our present means of investigation cannot detect them. It is not improbable that a disturbance of the normal flow of inpouring sensations, by means of various nervous and other diseases,, may underlie a large number of the phenomena of psychiatry. At all events, as the nervous system is the seat of the mind pre-eminently,. and as it is the apparatus upon which it seems immediately to depend both for its own portrayal, activity, and communication with the outer world, it is obvious that mental symptoms are of immense significance in neurology. A detailed description of these symptoms will be more appropri- ately considered along with the physiology of the brain. It may be noted here, however, that chief among them are the mental stigmata of degeneracy, a,bnormal emotional states with exaltation or depres- sion, delirium, maniacal violence, illusions, hallucinations and delusions, loss of consciousness, or coma, double consciousness, amnesia, aphasia, word-deafness, word-blindness, agraphia, etc. Motor and sensory symptoms have very dissimilar diagnostic valu- ation. The motor symptoms, being objective and capable of being ex- amined apart from the patient's consciousness, are the more definite, distinct and reliable to base a diagnosis upon. The sensory symptoms are almost wholly subjective. To be sure we can infer a good deal objectively in reference to them bv varving ourselves the stimuli that provoke them and by testing them in the reflex arcs ; but nevertheless even here it is practically impossible +o- eliminate entirely the patient's consciousness during their examm^ tion. Under ether narcosis they are not in evidence even in relation to the reflex arcs. Too much stress, therefore, should not be laid upon sensory phe- nomena except in association with others. They are, however, the most important symptoms to the patient and sometimes the onlv ones. Their greatest value, after their reality has been positively determined, is in the localization of the lesion. The psychic nature of hvsteria is all but positively affirmed by the peculiar distribution and prominence GENERAL CONSIDERATIONS UPON NERVOUS DISEASES 4/ of its sensory symptoms. A moving myelitis can sometimes be beau- tifully watched by the rise and fall of the border-line of anaesthesia. The symptomatic significance of the various forms of sensory dis- turbance will be referred to again in the introductory chapters to the special diseases. Only some general features will be noted here. There are five forms of sensation, commonly spoken of as gen- eral and special sense. Biologically they are all evoluted out of com- mon or simple touch sense. So far as the nervous apparatus itself goes there are nothing but afferent impulses. The naming of these impulses, touch, pain, heat and cold, sight, smell, taste and hearing, is the result of the special end-organs in connection with the nerves. A nervous atrophy that produces blindness, for instance, is no different from a nervous atrophy that produces cutaneous anaesthesia; the form of nervous lesion that causes auditory hallucinations may be exactly the same as the form of nervous lesion that causes a parsesthesia. With all the sensory phenomena, therefore, there should be a most careful determination as to whether the lesion resides in the outer end- organs, the receiving brain centers, or the intervening nervous pathway. It would be ludicrous, if it were not so tragical, to note how frantic- ally and persistently glasses are worn and changed, even upon the recommendation of careless and ignorant opticians, for a fading eye- sight, when an examination of the eye-ground would reveal a progres- sing optic atrophy. It is a common fact for the pains of tabes, a central disease, to be mistaken for the pains of rheumatism, a peripheral trouble. The diagnosing of the presence of a sensory disturbance is not enough. It must be determined why and wherefore the disturbance is present. In the skin are located three forms of common sensation, namely, touch, pain and temperature sense. In the muscles, tendons, fascia, joints and contiguous structures there is what is called a muscular sense, a sense which gives us some- what an idea of the location of the limbs. The nature of the latter sense is not clearly established yet and some authorities even doubt its existence as a special sense. The cutaneous and muscular senses are as much dependent upon special end-organs for their differentiation as are the so-called special senses of hearing, smell, taste and sight. When a sensation is excessively or abnormally acute we speak of the condition as hypercesthesia. When it is abnormally dull we re- fer to it as hypcesthesia. If it is absent entirely it is armsthesia. Per- verted sensations such as numbness, "pins-and-needles" feeling, formi- cation or the sensation as of ants crawling over the skin, are known as parcesthesia. These terms have been so universally applied to the tactile sense alone that, I am satisfied, it has had a good deal to do with keeping alive the common notion that special sense is in some way something extraordinarily different from the sense of touch. Nerve blindness is nothing but optic anaesthesia ; visual hallucinations, like flashes of light, fortification figures, are really, when of nervous origin, only instances 48 GENERAL CONSIDERATIONS UPON NERVOUS DISEASES of Optic parjesthesia. This should never be forgotten as it will save one from propounding such absurd questions as, Why should blind- ness occur in hysteria along with cutaneous anaesthesia, as a notable symptom? A proper knowledge of the basic character of all sensa- tion would cause the question to be asked, Why shouldn't it occur? Disease, it must be remembered, may attack the end-organs and produce hypersesthesia, anesthesia or parsesthesia ; a cataract produces blindness ;' a scar in the skin causes local loss of sensation ; the loca- tion and lesion are unlike but the manfestations are the same, anaes- thesia, but not pure neural anaesthesia. Atrophy of the optic nerve and atrophy of the spinal sensory nerves cause respectively loss of vision -and loss of the sense of touch ; the lesion is the same but the location merely is different. That is pure neural anaesthesia. Destruction of the visual centers in the occipital cortex and destruction of the sen- sory centers in the parietal cortex alike cause sensory anaesthesia. The universality of irritability in the nervous system is a most im- portant fact for it helps to give valuation to these phenomena as a means of localization, since it is thus varied merely by reason of the connections which the nervous apparatus makes. In this respect the sensory apparatus is the same as the motor M^herein we localize lesions chief! V bv the particular muscles with which it is connected. For the alterations in the pain sense we use the terms hyperalgesia and analgesia. Sometimes pain arises spontaneously in an analgesic area. This is known as analgesia dolorosa. Therman