From Clouds to the Brain. Celine Cherici

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      Reasoning from Malacarne’s observations of the proportion between the development of intellectual faculties and the number of superimposed blades of the cerebellum, he argues that this organ is formed by an aggregation of small galvanic cells. [BAY 25, pp. 798–799, author’s translation]

In 1808, he developed a project in which he designed a series of electrophysiological experiments in which brain slices were connected together like a galvanic column, in order to find the cerebral source of the human machine’s animating fluid. He thus presented the experimental steps necessary to verify the brain organ as a source of animal electricity. The physiological theory according to which the brain would produce, in the same way as a voltaic pile, electricity allowing the body to move, was based on a double metaphor: the first was mechanistic and compared the functioning of the brain to that of a machine; while the second was based on the identity of the shape of the galvanic column with the morphological organization of the brain structures. Animal electricity was conceived as the cause of the anatomopsychological nature of man. Beyond the source of the movement, this project tended to seek in galvanism, a “[…] phenomenon as important for animal functions” [MAL 08, p. 126, author’s translation], a similar functional principle for the expression of intellectual faculties and nervous mechanisms. Brain function was thus brought back to form: “[…] by beginning to subject to it those parts of the brain whose structure is visibly closest to the galvanic column, i.e. the cerebellum, and then moving on to the brain itself […]” [MAL 08, p. 128, author’s translation].

      The heuristic fertility of this analogy between the electricity-generating machine and the nervous productions of the brain lay in the resemblance of the structures, from which was induced an identity of the mechanisms:

      Let us assume six hundred and add the three hundred slices of the cerebellum that we observe and compare this machine with the galvanic column formed by nine hundred discs, also assuming some analogy in the activity of exercising galvanism. Shouldn’t we expect these powerful phenomena we admire in individuals to be produced by a hitherto unknown prerogative of the nervous and cerebral system? [MAL 08, p. 125, author’s translation]

      This research was linked, on the one hand, to neuro-anatomy, since no experiment could be undertaken without prior anatomical knowledge of the central nervous system, and on the other hand, to the experimental dimension of the recordings that Malacarne planned to make. The analogy of the cerebral structures with the galvanic column is traditionally attributed to Luigi Rolando (1773–1831), who from 1809 [ROL 09] stimulated the different parts of the column with current and thus caused violent convulsive phenomena in animal cerebella. In 1810, von Paula Gruithuisen (1774–1852) [GRU 10] described the cortical substance as an inexhaustible source of nerve power and stressed that it was a secretory organ. Reil imagined the cerebellum as a kind of voltaic pile, based on its histological aspect and the idea of a natural circuit. In 1840, Baillarger (1809–1890) [BAI 40] described the cell layers of the cerebral cortex and recommended that with its six alternating sheets of white and gray substances, it would be most similar to a battery and therefore suspected of making animal-electric fluid. The analogy of brain structures with a battery provided a morphophysiological model of a natural circuit conducting electricity from one point in the body to another:

In the cerebellum, there are a large number of separate slices superimposed on each other and joined together by a kind of conductor like the two elements of a galvanic cell. It is also noticeable that the nerves are formed of uninterrupted threads from the brain or spinal cord to their destination, and that these threads are usually wrapped in a fatty material that completely isolates them from each other and from neighboring parts; this gives these nerve conductors much resemblance to the silk-covered metal wires so often used to conduct electricity from one place to another without loss of power. [PAL 47, p. 39, author’s translation]

      Although animal fluid and electric fluid were often compared, there was still some ambiguity: their different applications did not require the same equipment. Animal fluid referred to the organic secretion of an energy similar to electricity. However, imagining a brain conceived as the driving force of the human machine, in a holistic perspective, included the production of normal and pathological thought, ideas and mental content. Considered to be responsible for behaviors considered as deviant, disturbances of the electrical cerebral organization needed to be medically and technically taken care of. This research was the catalyst the historical and conceptual articulation of the dominant influence of physics on the life sciences and of a medical discourse that attempted to understand the particularity of cerebral mechanisms in their organic and moral dimensions. Thus, galvanism referred to an imagination of the power of the human brain and contributed to basic cerebral myths on its unknown powers, such as telepathy or telekinesis:

      When the Voltaic pile produces incredible phenomena, when all the bodies of nature act and react upon each other, when electricity perhaps presides over all physical and vital phenomena, when its powerful action is perhaps not alien to the reproduction and evolution of living bodies, can we say that nervous action, the nervous fluid, the animal electricity, the magnetic fluid, any word, emanating from the brain of man, whose two substances and their numerous and deep convolutions perhaps form an animated electric instrument, can it be affirmed, I say, that this nervous fluid, after having been powerfully directed at the fingertips, cannot go beyond the limit of the nails? Can it not ally, unite and correspond with another person’s nervous system and impress them? [PIG 39, p. 41, author’s translation]

The beginning of the 19th Century marked the construction of a culture of physical, biological and medical electricity, of which today’s medicine still bears the traces. The links between the development of techniques for transmitting, stimulating and measuring electricity and progress in understanding the body were close. They were strengthened by work on the brain, with the conceptual background of the problem of how electricity maintains unity between mind, body and world. For galvanic doctors, there was no longer any doubt about the electrical nature of a mind-body connection. Thus was born the concept of an electric brain on which it was possible to intervene in order to modify, repair and/or contain the mind. As early as 1810, Matthew Yatman published a treatise entitled Galvanism, proved to be a regular assistant branch of medicine; also, “Interesting Inquiries concerning this influence, with regard to Living Actions” [YAT 10]. As a preamble, he describes animal fluid as the key to understanding all scales of life, from involuntary movements to conscious acts:

      The animal vital principle, formerly called ‘The Nervous Fluid’ is the connecting medium between mind and body; the source and regulating spring of animal sensation and expression, action and motion, both voluntary and involuntary; comprehending the circulation of the blood, respiration and all the other vital functions, or living actions. [YAT 10, p. 3]

      This harmonious communication between all levels of the organism took place, under what he called, the electrical influence formed in the lungs by the action of respiration, producing oxidation and chemical changes in the blood. Indeed, he took up the theme, largely theorized after 1740, of the influence of natural electricity present everywhere and absorbed by the mechanics of the body. The consideration was that the brain plays a central role in this modeling of the body as it separates electricity from the blood and transmits it throughout the vascular and muscular system, producing action.

      Electricity developed as an exploratory science of the central nervous system of control and improvement. This conceptual framework, linked to the current concept of increasing and improving capabilities, triggered a flurry of advertising promoting the merits of electrical accessories capable of improving mores by improving behavior. The fact that electrical treatments were seen as cures for virtually all diseases of the body and mind, from neurasthenia to epilepsy, was a result of this societal imaginary. The term culture, applied to electricity, took on its full meaning:

Such ideas about the hierarchical ordering of the body and society also made sense in light of the connections formed in the early nineteenth century between nervous impulses and other imponderable forces. If nervous impulses acted like СКАЧАТЬ