Emanuel Swedenborg's Investigations in Natural Science and the Basis for His Statements Concerning the Functions of the Brain

by Martin Ramström

ON THE CENTRES OF THE MOTOR FUNCTIONS.

Swedenborg also placed the centres of the soul’s motor activity in the cerebral cortex (See Œc. R. A., No. 127, etc.).

I have not been able to find anything of this kind even hinted at in the antecedent literature. We are reminded of how preceding authors, who made an attempt at some kind of localization of the origin of motion, in most cases placed this in the medulla of the brain, as for example the Bartholins;[67] and also Boerhaave.[68] And as we have just heard, Haller still held the same view.[69] Nevertheless Swedenborg expresses his conception without the slightest hesitation, and this he did because he regarded it as resting on a sure foundation. His strongest grounds and proofs were here also derived from the clinical and pathological observations in certain cerebral diseases which had caused changes in the cortex, and in patients, who had been injured in the cerebral cortex. It was these clinical cases at which I hinted just now. And now some of these may be brought forward, for the most part as Swedenborg himself has related them—with some few abbreviations:

A female seventy years of age, who after exhibiting the premonitory symptoms of apoplexy for some months suddenly lost the power of speech, and on being conveyed to bed, lost all sensation and motion. On a post mortem examination a large cavity was found in the cortical substance of her brain (›in ejus Cerebri substantia corticali ampla cavitas reperta fuerit›, see Œc. R. A. II., No. 154). The case was taken from J. J. Wepfer’s ›Historiae Apoplecticorum› (Amsterdam, 1681, pp. 5-11).

Another case taken from Wepfer was the following: A man 50 years of age had for some weeks before his death suffered from excruciating headache, the pain of which sometimes drove him mad, so that he was not seldom unconscious of what he said and did. On examining his head after death, the whole surface of the cerebrum and cerebellum, including both the convolutions and the furrows between them, seemed to be clogged all over with a gelatinous substance, from which, when it was pricked with a lancet, genuine serum oozed out. And also the very substance of the cerebrum and cerebellum had imbibed a large quantity of serum. (Œc. R. A., loco cit. and J. J. Wepfer: Op. cit., p. 15-19).

A case from A. Pacchioni was as follows: A young man had died under symptoms of fever, severe headache and spasms, or cramp. On opening his cranium, it appeared that the firm fibrous membrane of the brain, the dura mater, was loosened from the bone on the top of the head; and here, according to the description, it had exercised a strong pressure upon the underlying portion of the brain and was tightly adherent to it. (Œc. R. A., loc. cit.)——Consequently, in the last two cases: inflammation of the membranes of the brain, or meningitis with accompanying influence upon the superficial layer of the brain, the cerebral cortex.

And still another case from Pacchioni, which was still more convincing: A youth was brought into the hospital in an almost unconscious condition, spoke incoherently, cast himself about in all directions, etc.; and furthermore——his lips were somewhat drawn over to the left side (›labris ad sinistrum paululum detractis›), thus a right-sided facial paralysis! On examination after death no injuries could be found upon the integuments of the head, nor upon the outer or inner sides of the cranium, but on the left side of the brain a depression of the cortex was discovered, occasioned by the formation of a tumor or ›bladder› on that part of the surrounding dura mater lying just over the place of depression: ›ibi depressus et durioris consistentiae cortex cerebri cavernam ostendebat vesicae congruentem.›[70]

Swedenborg brought forward still more cases, so incomplete, however, that it is not worth while to repeat them here. But he had at hand a very large number of cases, as he says: ›phalanges observationum idem testificantium› (Œc. R. A. No. 154), or, as he says in another place, so many that a bare enumeration of them would fill two whole pages (Œc. R. A. II., 154).

Swedenborg had made a specially careful study of a great many cases of apoplexy and hemiplegy, which naturally, in so far as they affected the cortex, gave him direct guidance in judging of its function. And he also understood very well how to judge at the same time with regard to the importance of bleedings in the soft membrane of the brain, the pia mater, on and between the convolutions of the brain, the ›gyri›, and the pressure that these exercise upon the cortex, and the results of prevented circulation in cases of apoplexy. For in all these cases, he says, the transmission of blood to the cortex is checked, and by this the cortex was disturbed in its function, and this was the cause of the loss of sensation and of the paralysis. (Œc. R. A., III., No. 411 and III., No. 413; see also ›The Brain›, No. 89).

But Swedenborg had also directed his attention to that method of investigation which, to the brain physiologists of the present day, is the best aid for the examination of the motor functions of the cerebral cortex, namely, experiments on animals. He quotes such experiments, in which incisions had been made into the cortex ›just to the marrow›, as it is expressed, (›usque ad substantiam medullarem› [Ridley], Œc. R. A., I., No. 505); or when the brain (in dogs) had been pierced, (Œc. R. A., II., No. 154), and how these injuries had occasioned spasms or contractions of the trunk or extremities (Ridley). He also describes such cases in which fine needles had been pierced through the dura mater and corrosive liquors introduced through the holes, with the result that severe disturbances occurred in both motility and sensibility, and also how through such injuries muscular contractions had been provoked, by which it was sometimes observed that with certain stimuli the contractions first occurred in certain groups of muscles (for example, in the head or neck) and afterwards spread to the other parts of the body. (Baglivi ›The Brain›, No. 20).

As will be seen, these experiments were no ›precision-investigations›; and the same may be said of the clinical and pathological ones. And this may be the more easily understood, when we consider that in those times so much interest was not attached to such special observations of pathological changes in the cerebral cortex; for this was then regarded only as a gland, a secreting organ or reservoir for the ›spiritus animalis›. These observations were therefore made more as it were in passing. The same is also true of the experimental investigations on animals, quoted above. These were in reality made not in order to investigate any function of the cortex, but for other purposes, namely, in order to search out the causes of the pulsations of the brain, or the qualities and functions of the dura mater, etc.

Yet, as we shall see later on, some of the cases, in the original descriptions, really contain statements somewhat more exact and of greater interest even for the theory of cortical localizations, than those which Swedenborg quoted; but he seems to have here adduced no more than what had reference to the cortex regarded as a whole, and which showed what great changes in both the power of sensation and motion injuries in the cortex could produce. If we take this into consideration, and if we synthesize all these experiences, and add to this the increased knowledge concerning the minute structure of the brain, which had been produced especially by Malpighi’s discoveries, we must admit that Swedenborg had good reasons for his view that the soul’s activity had its seat in the cortex of the cerebrum.