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“ 5. That the medullary neurine is moulded into cords and bands—the nerves and commissures.” P. 329.
The functions of the nerves are thus described :
“ The experiments of Sir C. Bell, Magendie, and Mayo, have proved that there are nerves subservient to sensation-sensiferous or sensory nerves, and nerves of voluntary motion. The physiological researches of Whytt, Prochaska, and, more perfectly, Marshall Hall, confirmed by the anatomical observations of Grainger, Carpenter and Newport, have established another system of nerves for the involuntary—the conservative movements of the body under the title of the excito-motory system of nerves. All sound research and careful experiment prove that a nerve in the whole extent of its course, whether that course is between the fibres of a muscle, in the canal of a bone, in the substance of the spinal cord, in the crura of the brain, or in the masses of the hemispheres, always performs one and the same office, conducting always in one and the same direction.” P. 330.
In approaching the complex organs enclosed within the skull, Mr. Solly is impressed with the same difficulties that have obstructed all physiologists labouring in the same field : vivisections, comparative anatomy, and pathology, have thrown much light upon the mysteries of the mental phenomena, but still the curious inquirer is but too often doomed to disappointment. The author is inclined to adopt a theory, already advocated more or less by several eminent writers, among whom may be enumerated Drs. Todd and Carpenter and Mr. Bowman, to the effect that certain masses of grey matter the auditory ganglia of the medulla oblongata, the tuber. cula quadrigemina, the optic thalami, and the corpora striata, are, independently of the cerebral hemispheres, so many separate "sensorial centres,” that is distinct organs of perception.
As there appears to us to be some obscurity, if not contradiction, in the views which Mr. Solly states he has adopted from Dr. Carpenter, we prefer presenting them to our readers in his own words.
“ The anterior and posterior cerebral ganglia are regarded by Dr. Carpenter as forming part of the series of sensorial centres, of which we have seen other members in the olfactory, optic, and auditory ganglia. That they are independent centres of action, not mere appendages to the hemispheric ganglia, appears from the large quantity of vesicular neurine which they contain ; and that the corpora striata are so, further appears from the absence of any correspondence in size between them and the hemispheric ganglia. Thus in fishes, we find that the corpora striata make up the principal bulk of the second pair of masses; in reptiles, birds, and the lower Mammalia, they still form a very large portion of that which is commonly termed the cerebrum; and their subordinate aspect in man and the higher Mammalia is solely due to the large relative development of the hemispheric ganglia. On the other hand, there is scarcely any rudiment of the thalami optici to be discovered in fishes; their proportional size increases in reptiles, birds, and the lower Mammalia ; but it is only in man that their dirnensions approach those of the corpora striata. The peculiar connection of the thalami optici with the posterior columns of the spinal cord, and their great development in man, suggests the idea that they are the ganglia of tactual sensation ; whilst the connection of the corpora striata with the anterior columns indicates their relation with the motor function. The very close relation between the thalami optici and the corpora striata-corresponding, as Messrs. Todd and Bowman have suggested, with that which exists between the posterior and anterior peaks of grey matter in the spinal cord-harmonizes well with the fact that
Seat of Sensation and Volition.
the greater number of muscular movements are directed by common sensation ; whilst the special connection established by the inter-cerebral commissure between the corpora striata and the optic ganglia (tubercula quadrigemina) explains the peculiar influence of the sense of light in directing certain classes of muscular actions. The communication which is formed by the medullary substance of the cerebrum between these ganglia and the hemispheric ganglia seems to be the medium by which sensations are transmitted to the latter, to become the stimulus of intellectual operations, and by which the influence of volition is transmitted downwards to excite muscular motions through the corpora striata." P. 334.
In addition to these functions, the “whole chain of sensory ganglia is regarded as the centre of those automatic muscular movements which differ from those of a simply reflex character in being dependent upon sensation;" such as the instinctive actions of the lower animals, and a variety of actions performed by the human being—the consensual movements of the eyes, the regulation of the laryngeal muscles in the production of vocal sounds, the convulsive movements in hydrophobia, brought on by the sight or sound of water, &c. As to the hemispheres, they are the exclusive organ of the mental functions—the instrument by which the sensorial impressions are not only perceived, but are converted into ideas.
As we have already stated (Med.-Chir. Rev. 1845, p. 490), some of the reasons which may be adduced in opposition to these doctrines, we would only observe further that, up to the present time, they have not been reconciled, so far as they relate to the seat of consciousness, with certain familiar and admitted facts in physiology and pathology. One or two of these only can be now quoted : if both hemispheres be removed in a dog, as in Hertwig's experiments, the animal does not hear the report of a pistol ; if the hemispheres be excised in a pigeon, sight and hearing are abolished; if effusion of blood take place into the substance of one hemisphere above the corpora striata and optic thalami, or if from fracture of the skull a portion of bone be driven into the same part, inducing softening and suppuration of the white fibrous matter, there is paralysis more or less complete of the opposite side of the body. Now in all these and similar instances the assumed “sensorial organs,' “ the whole chain of sensory ganglia,” are left intact; and yet the phenomena of consciousness, attributed by this theory to them—vision-audition—tactual sensation, and voluntary motion, are destroyed. There is one fact connected with these cases, which is most significant; and which, whatever theory is adopted as to the organ of perception, must ever be regarded as the clue to the whole subject of paralysis and convulsion, as far as the brain is involved : we allude to the well-known circumstance that, in effusion and compression connected with one hemisphere, the paralysis is on the opposite side of the body. This is a clear demonstration that the decussating fibres already noticed, constitute, in reality, what physiologists contend they are, isolated conductors; for the mischief is traced precisely by following their remarkable and peculiar track. This fact, and the no less instructive cases of paralysis affecting special muscles of the orbit, further indicate that every affection of convulsion and palsy connected with the cranial nervous centres, however complex and apparently contradictory they may be, must be studied in strict reference to the course and destination of the primary fibrillæ. That the whole subject is still involved in much difficulty we are most ready to admit; but at the same time we must reiterate our conviction, that this will never be removed till physiologists, by returning to the doctrine formerly received, namely, that the cerebral hemispheres are the exclusive seat of all consciousness, shall place their conclusions in harmony with the unquestionable results of pathology. In treating of convulsive affections Mr. Solly quotes some extremely apposite remarks of Lallemande, to which, as bearing on the question just considered, we would call the attention of our readers (p. 554 et seq.)
Although we have ourselves no faith whatever in the truth of phrenology, it wonld be inconsistent with candour to withhold the author's arguments in favour of this popular doctrine.
“ My reasons for believing that there must be a great deal of truth in phrenology are fourfold. First. I have received from practical phrenologists, and especially the late worthy Mr. Deville, such accurate characters of individuals known to me, but unknown to them, that I cannot believe the accounts I received could be the result of accident and conjecture, which must have been the case if phrenology is untrue.
“ Secondly. Phrenology alone—as it appears to me-can account for all the varieties of insanity, especially monomania.
Thirdly. The facts which have been collected by the late Mr. Deville, showing that the brain will alter its form at any period of life.
“ Fourthly. The existence of longitudinal commissures.” L. c., p. 339.
We need scarcely remark that great importance is attached by phrenologists to the evidence derived from the investigation of insanity. Upon this most interesting subject Mr. Solly observes :
“. If phrenology is true, insanity on its first ingress is frequently not a disease of the whole brain, but of only a part of it. The first effect of inflammation is to excite to an unnatural degree the natural function of an organ. The function of the organ thus exalted obtains a mastery over the rest. For instance, a man, from defective education, combined with hereditary tendency, allows his love of approbation, his vanity, in other words, to grow with his growth, and strengthen with his strength, gradually becoming the sole ruling principle of life: at last it, instead of reason, so completely guides and regulates all his actions, that they are contrary to reason, and justly called the acts of a lunatic. Yet all this may go on with reasoning faculties so acute, that he conceals the dominant feeling of his breast, the mainspring of all his actions, and in a court of law deties any one to prove him insane.
“ The great amelioration which has been effected in the condition of the lunatic has been founded on this principle, that none are so mad as to be incapable of appreciating kindness. Throughout all the admirable and interesting reports of Dr. Conolly, it will be seen that this has been the guiding principle of his boldly humane treatment. The first thing, says this admirable man, is to gain the confidence of your patient; and that once obtained, you may do anything with him.
“ Now if this is true, (and no one who has treated the insane on these principles doubts it,) so is it equally true that they may be awed by punishment and even acknowledge its justice. Only the last time I had the pleasure of visiting that noble asylum, Hanwell, I listened with much interest to a lunatic whom we met in the grounds. He began by requesting Dr. Conolly to procure his release from the Asylum, and then went on in a rambling manner, reasoning on things and circumstances which had no existence, showing his mental aberration; but he finished by saying, as an argument for his being allowed his liberty, that he 1847]
On Anamic Coma.
had always conducted himself with propriety while there, which was perfectly true. This sense of right and wrong was as perfect as ever, and this sense enabled him to conduct himself properly. But if he had supposed that the circumstance of his being lunatic gave him a license for any conduct, and freed him from all responsibility, would he have been so anxious to conduct himself properly? And if he were told that the law of the land would not take notice of an improper act, even if that act amounted to murder of a fellow-creature, he would not feel the same reason for self-control.” P. 340.
The portion of Mr. Solly's work which treats of the diseases of the brain, is distinguished by a happy combination of practical observation with scientific research ; and as, in addition, the views of the most eminent modern writers are given in their own words, a comprehensive and valuable résumé of cerebral pathology as it is cultivated in the present day, is presented to the reader. In a subject so comprehensive, we can only select one or two of the more general topics for consideration. The observations of the author on derangements of the circulation, especially on the various forms of anæmic affection, are very judicious, and well worthy the attention of the practitioner. Those only who have carefully investigated the complex texture of the brain and spinal cord with the aid of the microscope, are capable of forming a just conception of the predominating influence that must be exerted on the actions of these organs by disturbance of their capillary system. Impressed with this conviction Mr. Solly, in considering the cause of the symptoms characteristic of cerebral anæmia, dissents from the opinion of Dr. Burrowes, that this consists of diminished pressure ; he thinks, and in this view we concur, that the mischief arises from the defective supply of blood in the capillary vessels.
“ We know that the function 'of all other organs, uninfluenced by pressure, may be excited by a flow of blood into them, or their function may be arrested by any stoppage in their supplies. Take the salivary glands or the testicles, as an illustration : mental emotions will both excite and arrest their secretions ; and I believe that the brain would be similarly affected, and to the same extent as now, even if that organ were not enclosed in a spherical box, and supported on all sides by the cerebro-spinal fluid.”—L. C., p. 349.
In speaking of anæmic coma, the author enforces the necessity of well distinguishing between this affection and the coma arising from inflammation and effusion—a distinction of vast importance in practice, and for firmly establishing which the profession is mainly indebted to that admi. rable observer Dr. M. Hall. Although much attention has been paid to this class of affections, the following judicious observations of Dr. Gooch will not be here misplaced :
“ So inveterate is the disposition to attribute drowsiness in children to congestion of the brain, and to treat it so, that I have seen an infant, four months old, half dead from the diarrhæa produced by artificial food, and capable of being saved only by cordials, aromatics, and a breast of milk; but because it lay dozing on its nurse's lap, two leeches had been put on the temples, and this by a practitioner of more than average sense and knowledge. I took off the leeches, stopped the bleeding of the bites, and attempted nothing but to restrain the diarrhæa, and get in plenty of nature's nutriment, and as I succeeded in this the drowsiness went off and the child revived. If it could have reasoned and spoken, it would have told this practitioner how wrong he was ; any one, who from long defect in the organs of nutrition is reduced so that he has neither flesh on his body nor blood in his veins, well knows what it is to lay down his head and dose away half the day without any congestion or inflammation of the brain. This error, although I have specified it only in a particular complaint of children, may be observed in our notions and treatment of other diseases, and at other periods of life. If a woman has a profuse hæmorrhage after delivery, she will probably have a distressing headache, with throbbing in the head, noises in the ears, a colourless complexion, and a quick, weak, often thrilling, pulse, all which symptoms are greatly increased by any exertion. I have seen this state treated in various ways, by small opiates, gentle aperients, and unstimulating nourishment, with no relief. I have seen blood taken away from the head, and it has afforded relief for a few hours, but then the headache, throbbing, and noises, have returned worse than ever; the truth is, that this is the acute state of what, in a minor degree and in a more chronic form, occurs in chlorosis, by which I mean pale-faced amenorrhæa, whether at puberty or in after-life. It may be called acute chlorosis, and, like that disease, is best cured by steel, given at first in small doses, gradually increased, merely obviating constipation by aloetic aperients.”—L. C., p. 367.
The necessity of employing the microscope in the investigations of morbid anatomy, is strongly advocated by the author ; indeed, when it is recollected that the essential structure of every organ in the body-in fact the organ physiologically considered, is altogether hid from the naked eye ; that the capillary vessels, constituting the active part of the vascular system—the cells of the various glands, forming the real apparatus of secretion; the gray corpuscles and primary tubules composing the instrument of innervation, are each and all of microscopic dimensions, what reasonable expectation can there be of detecting those molecular changes, which constitute the first and essential alterations in all organic disease, so long as the examination is made by the unaided senses and the very objects implicated are unseen? In some instances, indeed, the microscope will do little more than disclose the real seat of the disease ; but in others, it will also reveal important indications explanatory of the true character of the disease. One of these latter cases concerns that obscure affection, ramollissement or softering of the brain, a subject on which the author has collected much valuable information. Our readers will recall the involved and contradictory opinions of writers as to the true nature of this affection; the long discussions whether it be, as Lallemand contends, inflammatory; or, as Rostan regards it, an affection entirely sui generis ; or, as Cruveilhier affirms it to be, capillary apoplexy, and so forth. In the midst of this confusion, Gluge had the great merit of discovering, with the aid of the microscope, a certain test of inflammatory action in many instances of cerebral softening, indicated by the presence in the affected part of exudation corpuscles, or, as they were termed by this writer, compound inflammation globules.” In some valuable papers published in the Edinburgh Medical and Surgical Journal, Dr. Hughes Bennett has shown, by a similar mode of investigation, that two kinds of ramollissement exist, an inflammatory and a non-inflammatory; that these are distinguishable microscopically by plainly recognisable characteristics ; and that inflammation in the nervous centres has, by these means, been demonstrated in several instances after it had escaped the search of good