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CHAPTER V.

THE BRAIN IS NOT THE ORGAN OF MIND-CASES OF DISEASED BRAIN WITHOUT IMPAIRED INTELLECT.

T is a pity for the two former schools already referred to, that they have not yet decided upon

what is the respective functions of the cerebrum and cerebellum. I know that by some intelligence is ascribed to the former-animal instinct to the latter; but there is nothing like unanimity among themselves on this point, several writers* having denied consciousness to the cerebral hemispheres. For instance, certain writers have placed the sensorium commune in the corpus callosum; others in the corpora striata; others, again, in the pineal gland, the medulla oblongata, certrum ovale, &c. But, as Mr Lewes has remarked, "they might as well have placed it in the jaw-bone, or any other bone, as far as any scientific warrant can be given for these opinions." And few good physiologists agree with Gall in assigning the

* Prochaska, Muller, &c.

sextual instinct to the cerebellum; but at the same time we have no good reason to assert with certain physiologists that this smaller brain is the organ of muscular co-ordination, because I think experiment has disproved it. Mr Solly, in his work on the brain, reports the case of a child whose cerebellum was entirely wanting, yet it reached the years of twelve, and only a slight part of the co-ordinating power was affected. And out of ninety-three cases of diseased cerebellum, Andral found only one to favour the opinion of physiologists; and, as we have already seen, certain animals are quite vivacious after their entire head is cut off, so that neither disease nor experiment-two very valuable evidences-favour the current opinion. Indeed, some men hold the cerebellum to be a seat of sensibility, as we may learn from the following remarks of a very eminent physiologist:-"The opinion advanced by some physiologists that the cerebellum is the regulator of the voluntary movements, if we attentively consider the reasoning on which it rests, seems to me to strengthen the idea which places the central seat of sensibility in the cerebellum." Others, again, assert that the medulla oblongata is a seat of sensibility and volition. Müller says that it is "the seat of volition;" and again, he states that "it is the seat of the faculty of sensation." Others say "That the medulla and the ganglia at the base of the cerebrum constitute the sole sensorium;" and we have already seen that sensation, &c., has been assigned to the spinal cord-so

that we find no unanimity among physiologists with regard to the functions of the various parts of the brain. This is a This is a pity for their own sakes; because they each disprove what the other has advanced, and the experiments of either contradict the experiments of all; and from this labyrinth of confusion how can we extricate truth? When the facts are at variance (which proves distortion somewhere; because truth is one, and one part cannot contradict the other-all truths must agree with the truth), how can we adopt a proper theory? But these men cannot but disagree, because they fight not for truth, but for the defence of a favourite theory. Physiologists, I am sorry to say, are not the only ones guilty of such conduct. I consider that these sadly contradictory theories tell very much against those who hold that brain is the organ of the mind; and their duty is to collect and classify more facts, and not waste their time and energy in defending a mere hypothesis. It is here worthy of remark that the medulla oblongata exists before the brain-that every part of the brain exists at the period of birth, and that the brain attains its full size at the seventh year. We will state a few cases where the brain was wholly or in part diseased, without any intellectual derangement ensuing :

1.* "A young man, aged eighteen years, had been for six or eight weeks troubled with a cough and * We are indebted to Dr Abercromby for these cases of brain disease.

pain in the chest, but afterwards complained of severe pain in the right temple; a couple of months passed with little or no convalescence, when the patient began to complain of pain at the back of the head, and in the course of another month he died rather suddenly, having the day before become extremely weak and pale without any obvious cause. Inspection: On removing the dura mater, there appeared on the middle of the right hemisphere a remarkable depression, which, when cut into, was found to arise from an extensive mass of pure remollisement (or softening of the brain), the part being in the state of a soft white pulp, without any appearance of pus, and without fetor; it extended the whole depth of the hemisphere. In the cerebral matter adjoining to this disease, there was a small abscess, no larger than a bean, lined with a firm, soft cyst of coagulable lymph. On raising the brain a remarkable appearance was found in the basilar artery. Through the extent of about an inch it was very much enlarged and hard, and this portion was found to be completely filled up by a firm white matter, without any appearance of blood." Now, one would think that if brain be the organ of mind, surely this youth's mind was deranged? Not so; we read "that speech and intellect were entire."

2. Another youth of eighteen, who had "the right hemisphere of his brain, to about half its depth, entirely reduced to a mass of fetid pus; in the centre

it was fluid, and towards the external parts it was more of a pulpy consistence. In this mass was found some small coagula of blood, and the ventricle contained a considerable quantity of bloody fluid." Notwithstanding all this disease, we do not read of any mental derangement; but, on the contrary, he was sensible, and knew all the persons around him.

3. Another young man, of the same age as the former two, had "the whole of the posterior part of his brain one mass of undefined suppuration. There was considerable deposition of coagulable lymph on the surface of the brain in several places, especially under the anterior lobes. There was a very small quantity of fluid in the ventricles, which contained considerable remollisement of the fornix. In the substance of the brain, near the base, there was a small tumour of an ash colour, which contained a cheesy matter approaching to suppuration," and other marks of disease, yet the mind was unaffected.

4. A young lady, aged eighteen, had "considerable effusion in the ventricles of the brain. In the substance of the right hemisphere there was a soft, tubercular mass of large size, and there was considerable remollisement of the cerebral substance surrounding it. There were two small tumours of the same kind in the cerebellum." This brain disease was complicated with extensive bodily disease; yet the lady appeared sen

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