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shall proceed at once to consider the different theories which have been from time to time promulgated as to the seat of articulate language.
The ancients seemed to have possessed the most crude notions of the functions of the brain, as evidenced by Hippocrates assigning the seat of the mind to the left ventricle, and by Aristotle also placing the sensorium commune in the heart; Michael Servetus, who flourished in the sixteenth century, believed the choroid plexus was the organ destined to secrete the animal spirits, that the fourth ventricle was the seat of memory, and that the habitation of the soul was in the aqueduct of Sylvius; a century later, René Descartes assigned to the soul a more secure position in the pineal gland. In later times, the brain has been universally considered to be the organ of thought and intelligence, but opinions have been and are still divided, as to whether it is to be regarded as a single organ, or as consisting of a series of distinct organs, each endowed with a special and independent function—whether, in fact, the phenomena of intelligence are due to an action of the brain as a whole, or whether the different psychological elements which constitute them are connected with isolated and circumscribed parts of the encephalon.*
Out of the last theory has arisen the principle of the localisation of the cerebral faculties, which was first announced in a definite form by Gall, who divided the encephalon into organs endowed with primordial faculties, distinct the one from the others. The germ of this
* Those who may desire more detailed information as to the various theories of the seat of speech which were in vogue before the time of Gall, I would refer to an extremely interesting series of papers recently published by the late Dr. Hunt in the Anthropological Review.
idea of the polysection of the encephalon is to be found in the writings of physiologists long before the time of Gall; indeed, one writer, Charles Bonnet, assigned a special function to each fibre, stating that every faculty, sensitive, moral, or intellectual, was in the brain connected to a bundle of fibres, that every faculty had its own laws which subordinated it to other faculties, and determined its mode of action, and that not only had every faculty its fasciculus of fibres, but that every word had its own fibre!
The circumstance which directed Gall's attention to the possibility of connecting the brain with certain faculties of our mental nature is so well known that I scarcely need allude to it. In his early days, he often found himself surpassed by certain of his fellow students whom he felt were intellectually inferior to himself, but in whom a remarkable memory coincided with a striking prominence of the ocular globes. This external prominence led him to the inference that there was an internal cerebral prominence which produced it, and it was the application of this reasoning to other cranial protuberances that gave rise to his craniological doctrine.
According to Gall, the brain is composed of various parts, to each of which a special function belongs, and his system embraces the topographical determination of each of these organs. The organs of the memory of words, of the memory of persons, and of the faculty of language, he located in the convolutions which rest on the floor of the orbit, and which form the inferior surface of the anterior lobe; the organ of the memory of persons he placed immediately above the inner angle of the orbit, that of the memory words in the convolution which rests on the posterior half of the roof of the orbit, whilst the organ of language or speech he placed in the convolution which rests on the anterior half of the orbital roof, in front of the preceding faculty.
The minute anatomy of the convolutions was unknown in the time of Gall, and he based his phrenological theories rather on the external prominences of the skull—on cranioscopy—than upon a careful study of the convolutions to which these prominences corresponded, and although his conclusions must be considered in many instances arbitrary and hypothetical, still I would say “Let not the spark be lost in the flame it has served to kindle,” for in spite of all that has been said against Gall, and all that has been written in depreciation of his labours, beyond all doubt, his researches gave an impulse to the cerebral localisation of our faculties, the effect of which is especially visible in our own days; and I look upon his work as a vast storehouse of knowledge, and as an imperishable monument to the genius and industry of one of the greatest philosophers of the present age.*
* Gall's labours would undoubtedly have met with a more hearty recognition from his contemporaries, had not the Austrian priesthood raised the cry of “materialism” as applied to his doctrines. The great German psychologist had no such heterodox notions as his adversaries maliciously attributed to him, for as Hufeland philosophically observes, “he was employed in analysing the dust of the earth of which man is formed, not the breath of life which was breathed into his nostrils."
As in Gall's days so in ours, this very indefinite and unmeaning word “materialism" is used as a kind of psychological scare-crow to frighten all those who are endeavouring to trace the connexion between matter and mind. Surely there is nothing contrary to sound theology in assigning certain attributes or functions of an intellectual order to certain parts of our nervous centre; the cerebral localisation of our divers faculties, and the plurality of our cerebral organs, strike no blow at the great principle of the moral unity of man.
Gall's conclusions were based purely on the study of anatomy, but subsequent observers - Bouillaud, Schroeder Van Der Kolk, and Broca-have brought the light of pathological observation to shine upon this obscure subject, and, with the view of testing the soundness of the respective theories advanced by these physiologists, I propose briefly to weigh the evidence which has been furnished for or against the four different theories which have, in modern times, been promulgated as to the seat of speech; and here I would observe, that this question will never be settled by mere theoretical speculation, without the aid of that inexorable scrutiniser of facts-necroscopic examination.
I will first discuss the theory which has perhaps found the fewest advocates that of Schroeder Van Der Kolk-who placed the seat of speech in the corpora olivaria, a theory which has lately found a warm supporter in M. Jaccoud, who thus expresses himself in reference to it;—“The functional centre of the articulation of sounds and of deglutition is situated in the medulla oblongata. It is constituted respectively by the union of the hypoglossal, the facial, the glossopharyngeal, the spinal accessory, and the trifacial nerves. For the isolated movements of the tongue, of the lips, of the cheeks, of the velum palati, and of the pharynx, each of these nerves acts independently in its sphere of distribution; but for the complex and simultaneous power that caused the earth “like a spark from the incandescent mass of unformed matter, hammered from the anvil of omnipotence, to be smitten off into space,” this same power, surely, could just as well ordain that a multiplicity of organs should be necessary to the full development of man's mental faculties, as that the manifestation of them should depend upon the integrity of one single organ.
movements which are necessary for the production of articulate sounds and of deglutition, all the original nuclei of these nerves are connected together, also the one side with the other, by the olivary system, which thus becomes the co-ordinating organ of the final functional
A more recent writer, M. Vulpian, criticises most severely Van Der Kolk's conclusions, and quotes a case observed by himself, where, although the olivary bodies were both manifestly diseased, yet speech remained perfectly unimpaired to the last.f
Of the sixty-three cases to which I have called attention in the preceding pages, I find that in five only the olivary bodies were stated as having been found diseased after death. The first three cases are quoted by Van Der Kolk. In one of these, in addition to atrophy of the olivary bodies, there was an extremely imperfect development of the frontal convolutions, and also a positively diseased condition of the anterior lobes; in another case, although there was found grey degeneration of the right olivary body, there was also disease of other parts, namely, in the crura cerebri, the corpus callosum, one of the thalami, the fornis, and the corpora pyramidalia; in the third case I have quoted from Van Der Kolk, as well as in one from Abercrombie, in addition to the disease in the corpora olivaria, there was also disease in one of the crura cerebelli and in the tubercula mamillaria ; and, lastly, in a case observed by Romberg, the affection of the corpus olivare coincided with disease in the right half of the pons Varolii. It must, therefore, be conceded, that as in all these
Gazette Hebdomadaire de Médecine et de Chirurgie, July 22, 1864. + Leçons sur la Physiologie générale et comparée du Systême Nerveux, p. 495.