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greater or less degree. Thus, Professor ROLANDO of Turin, who has devoted much of his time to the study of the anatomy and functions of the brain, in speaking of mutilations, which he had performed with a view to discover the functions of a particular part of that organ in the lower animals, complains of this as an almost unsurmountable obstacle. "I have made," says he, " innumerable experiments to discover the results of injuries done to the bigeminal tubercles, and the parts in the neighbourhood of the optic thalami, but I have rarely obtained consistent results; which is not surprising, if we consider the peculiar interlacing of the numerous medullary fibres which meet in these parts; for, as it is extremely difficult to know what bundles of fibres have been affected in these operations, we cannot draw clear and precise conclusions where there is a difference in the result." If this holds true with regard to mutilations performed with every precaution to avoid wounding other parts, and under every advantage which an acquaintance with anatomy can afford, it certainly applies with tenfold force to injuries, the results of accidental and unguided violence.

Lastly, That, from the mere aspect of the wound, we are never certain of the precise extent of the injury done to the brain; and, consequently, can never positively refer the phenomena to an affection of any particular part, and of it alone. One injury, for instance, apparently of the very slightest nature, often produces the most serious constitutional symptoms, and disturbance of the whole mind; while another, to appearance much more severe, is productive of little inconvenience. In the former, the effects of the violence seem to extend either immediately or from sympathy over the whole brain, or at least, much farther than its external or visible seat, while, in the latter, the affection is more strictly of a local nature; and thus the results obtained in one case are often entirely negatived by those obtained in another.

In accordance with, and in corroboration of the opinion

which I have here ventured to express, as to the total inadequacy of this mode of investigation for the purposes of original discovery, I would ask no better authority than Sir E. HOME himself. For although, for the sake of greater he confines himself to cases which have come unaccuracy, der his own immediate notice, and, although these must have been observed with a view specially to this inquiry; yet, his own essay on this subject affords the most convincing proof and apposite illustration of all the defects of the mode which it is written to recommend. The first things, for example, that strike the reader on referring to it, are, 1st, That out of the ten classes, into which the cases are purposely divided by Sir EVERARD, no less than seven, (1. Undue pressure of water on the brain, 2. Concussion of the brain, 3. Preternaturally dilated or diseased bloodvessels of the brain, 4. Extravasated blood, 5. Formation of pus, 6. Depression or thickening of parts of the skull, 7. Pressure from tumours), resolve themselves into affections, in which the totality of the brain is, in some way or another, concerned; 2d, That, in one, (viz. 8. Injury of the medulla spinalis), the entire brain is unaffected; and, 3dly, That in two only, (9. Injury to the substance of the brain; and, 10. Alteration of structure), is the affection generally confined to individual portions of that organ; although in very many instances, even in these two classes, it extends over the whole brain. From his own statement, then, the reader would naturally anticipate a priori, that the effects resulting from most of these injuries would be such as are known to indicate derangement, not of one, or of several, but of all the parts of the brain; and, consequently, that they could not, by any possibility, lead to the discovery wished for, of the functions of its individual portions. Accordingly, Sir EVERARD himself informs us, that the effects produced are, delirium, convulsions, coma, apoplexy, sickness, watching, and the like, and not lesion of any particular faculty, or of any individual function. In one or two instances, indeed, the state of the memory and of

the external senses is mentioned, but without being connected in any way with specific injury. The reviewer himself, with every wish to be pleased with Sir EVERARD'S method, is constrained to say, that the results obtained in this manner are so vague and contradictory, that they 66 serve only to confirm what had already perhaps been sufficiently made out by the authors we have named; to-wit, that there is no sort of uniformity either in the kind or degree of the symptoms which accompany diseases of the brain." And in this sentiment I cordially concur with him, in so far as regards violent injuries.

To render the results obtained, either from observing the effects of cerebral injuries in man, or from the performance of mutilations upon the brains of animals, at all valuable in illustrating the cerebral physiology, a previous knowledge of the seats of the organs, and of the nature of the faculties which they subserve, has been already shewn to be an indispensable requisite ; and if we suppose these to have been accurately ascertained by other means, then the facility of making interesting and precise physiological and pathological observations is so greatly increased, that much valuable information may be obtained; especially in some individual cases, in the two last mentioned classes of Sir E. HOME. But without this preliminary knowledge to guide us in our observations, it is obvious that nothing precise or practicable can be got at.

If an injury of the cerebellum, for example, or of part of the posterior lobes of the brain, occurs to a philosopher, who is firmly satisfied in his own mind "that the whole brain is engaged in every act of thought," and that no part of it is appropriated to the manifestations of any of the propensities or sentiments, what inference can he draw as to the function, upon finding no intellectual faculty with which he is acquainted impaired or wanting? He cannot consistently investigate the state of the propensities, and refer any irregularities among them to the injury sustained, because these are not intellectual faculties, and, according

to him, have no connexion with the brain.

He remains of

necessity as much in the dark as ever. But let such a case occur to the phrenologist, or to him who has ascertained, by previous observation, the uses of the part, it is evident, that, although he could not, any more than the philosopher, infer the function from a consideration of the symptoms alone; yet, having discovered it by other means, he comes to the inquiry fully competent to judge whether his former observations are confirmed or refuted by the phenomena now before him. It is only when in possession of this previous qualification that we can derive any advantage from such cases in increasing our knowledge of mind.

That the philosopher, with such views, could never have been led to the discovery of the connexion between certain parts of the brain and the propensities and sentiments, by the mere observation of their injuries, is proved by wounds of these parts having been actually attended with symptoms corresponding to their phrenological functions, and neither he nor the anatomical surgeon having drawn any such inference. Wounds and diseases of the cerebellum, for instance, have forced themselves upon their notice, where the sexual propensity was extinguished by loss of substance, or preternaturally excited by the subsequent inflammatory action; and yet no one drew the inference that the cerebellum was the organ of Amativeness*. The temper and moral sentiments have also been entirely changed, in consequence of certain injuries of the brain, while the intellect remained unimpaired; and no one drew the conclusion that the parts affected were the organs of these sentiments. Nor would they have been warranted in doing so, because instances of injury confined so entirely to one part as to affect its function, without having any influence upon those of the neighbouring parts, are so rare, in comparison to those of an opposite kind, that no just inferences can be drawn from them alone; although, combined with other evidence, they are highly important.

* WEPFERUS' Historia Apoplecticorum, edit. 1724, p. 487. MAGEN

CONCLUSION

(To the Second Edition.)

In the Introduction to this work, it is observed, that, "in surveying the philosophy of man, as at present exhibited to us in the writings of philosophers, we perceive, first, That no account is given of the influence of the material organs on the manifestations of the mental powers; that the progress of the mind from youth to age, and the phenomena of sleep, dreaming, idiocy, and insanity, are left unexplained or unaccounted for; secondly, That the existence and functions of some of the most important primitive faculties are still in dispute; and, thirdly, That no light whatever has been thrown on the nature and effects of combinations of the primitive powers in different degrees of relative proportion. It is with great truth, therefore, that Monsieur DE BONALD, quoted by Mr STEWART, observes, that, “diversity of doctrine has increased from age to age, with the number of masters, and with the progress of knowledge; and Europe, which at present possesses libraries filled with philosophical works, and which reckons up almost as many philosophers as writers; poor in the midst of so much riches, and uncertain, with the aid of all its guides, which road it should follow; Europe, the centre and focus of all the lights of the world, has yet its philosophy only in expectation."

May I hope that Phrenology will now appear to the attentive reader calculated to supply the deficiency here pointed out, and to furnish Europe, at last, with the Philosophy so long in expectation?

Hitherto the writings of Dr GALL have been little known to the British public, except through the medium of hostile

DIE'S Journal de Physiologie for April and August 1822; also Medical Repository, vol. xviii. p. 268–358.-LARREY'S Memoires de Chirurgie Mi. litaire et Campagnes, vol. ii. p. 150; vol. iii. p. 262.

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