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

by Martin Ramström

(Thus, for example, Swedenborg describes the optic thalami as such a secondary centre in the course of the path of sight;[35] and the corpora striata in the path of the sense of smell;[36] and the origin of conscious tactile sensations he describes thus: — — — ›rudior quicunque tactus a superficie totius per medios nervos in Medullam Spinalem aut Oblongatam et abinde in activissimum cinerem, et in circumfusum corticem Cerebri emicet: Adeo ut extremi receptus modorum sint in cortice Cerebri, qui conscius redditur mutationum in seriebus et substantiis compositis usquam contingentium.› Œc. R. A. II., 192).

Thus: although Swedenborg did not suppose the ›Cerebellula› to be arranged into sensory centres in the same manner as we do, still he seems to have supposed an arrangement something resembling this, with Cerebellula-groups as subdivisions of the great sensible centre-organ, which is formed by the ›Cerebellula› of the brain cortex, taken together, and which Swedenborg called ›Sensorium commune.›

In regard to the relation of the cortex to motility, Swedenborg expresses himself much more definitely. This activity of the brain Swedenborg also regarded as derived from the small cortical elements, the ›Sphaerulae› or ›Cerebellula›.[37] He ascribes to them, on the one hand, a high degree of self-determination, so that they could perform their functions independently of each other, this on the basis of certain anatomical conditions, such as their position in respect to each other in separate cavities, and their connection each with its own special nerve-fibre, and, besides, also on the basis of certain clinical and pathological observations;[38] but on account of other anatomical conditions, such as the aggregation of the ›Cerebellula› into larger and smaller groups, as into gyres, and groups of gyres, etc., as well as on certain other grounds, he ascribed to them also the ability to cooperate with each other when necessary.[39] In consequence of this the brain possesses, as he says, the power and choice of influencing whatever nerves and muscles it will, and of stimulating them to activity. (›Proinde Cerebri secundum ordinatam ejus substantiae dispositionem in potentia et arbitrio est, quascunque velit fibras, aut fibrarum fasciculos, et consequenter nervos et musculos inspirare et ad agendum excitare.› Œc. R. A. II., 153). It was impossible for him to express himself as to what parts of the cerebrum or which convolutions, gyri, correspond to the respective muscles, but he refers to experimental investigations of animals, by which this might be discovered.[40]

But although the brain would then be able to govern every muscular action, it was not employed every time such an action was to be performed. No, in the medulla oblongata and in the grey substance of the spinal cord there were subordinate, secondary motor centres, and these governed the automatic and habitual movements, so that, for the performance of these, the brain need not be disturbed in its higher functions. Only for the purely voluntary motions were impulses from the cerebrum necessary.[41]

Swedenborg has thus clearly located the ›causa principalis› of the voluntary movements in the cortex of the cerebrum, or more definitely, in the cortical elements and in groups of such elements, although in this work ›Œconomia Regni Animalis› he did not succeed in more closely defining the position of the various motor centres.

From all that I have here brought forward concerning the functions which Swedenborg ascribes to the cortical substance of the brain, it is evident that he succeeded in coming to the full conviction that it is through the activity of the ›Cerebellula› (or as we express it, through the cerebral nerve-cells) that the perception of sense-impressions and the impulses to voluntary motions arise.

But Swedenborg does not stop even here. The elements of the cerebral cortex, he continues, are still not the ultimate determinants. They are only, so to speak, the inner sense-organs[42] and sub-determining media.[43] They are themselves subordinated under the understanding and the will, and their principle, the soul.[44] The soul, the principle of life, it is the soul, which, through those cortical elements, perceives the external world: it is the soul which feels, sees, hears, smells, tastes, it is the soul which recollects, thinks, performs, and wills; it is the soul which speaks and acts.[45]

What then is the soul, and where does she reside?

The seat of the soul must surely lie in the cerebral cortex; at least its activity comes into play there, and still more definitely, in the ›Cerebellula› of the cortex. (See above and also ›The Brain›, No. 7). But what is she? What is the soul?

Here Swedenborg makes one attempt after the other to draw away the obscuring veil. Sometimes he thinks of the soul as only dwelling and working in the ›Cerebellula› and their ›fluidum spirituosum›; but in this way he does not come to a solution of the principal question, which is only removed farther away.[46] Sometimes he thinks the soul to be identical with the ›fluidum spirituosum›; but how can this, however subtile fluid, be immortal? Here he is again repulsed.[47] He discusses the supposition that, although the ›fluidum spirituosum› in itself is not immortal, it yet becomes so upon the death of the body, and so forth.[48] And at last he bursts out with: ›it amounts to the same thing if we see in this fluid the soul itself, or only its faculty of imagination and judgment, for the one cannot be thought of without the other.›[49]