Название: From Clouds to the Brain
Автор: Celine Cherici
Издательство: John Wiley & Sons Limited
Жанр: Физика
isbn: 9781119779506
isbn:
One can wonder about this imaginary electrical singularity of an organism suffering from nervous disorders. It must be brought closer to the notion of a body designed as a natural electrical machine. If the sensitivity and excitability of the nerves depended on a personality marked by a more or less nervous temperament, the medical applications of galvanism were fairly quickly focused on nervous disorders. This fact influenced its reception in the medical world:
No doubt people of excessive nervous susceptibility are usually well served by a bath or simple galvanic current, so M. Labeaume’s method must be useful to patients with an eminently nervous constitution. [LAB 28, p. 25, author’s translation]
Also experimenting on human chains15, Humboldt quickly noticed the variability of conductivity from one person to another, which could be almost zero in some people. This observation completed the question of a subject’s electrical temperament; this temperament influencing both body and consciousness.
To conclude this chapter, here is a current scientific episode whose rigor is not to be judged, but to underline its inscription both in the long temporality adopted in this work and in a scientific imagining of the neuro-electric omnipotence. In 2016, a controversial article appeared on the Frankenstein effect. Canavero, known for his research in the field of human head transplants, using Aldini and Ure’s experiments, took up the following theme:
Data from two centuries ago prove that a fresh cadaver, after hanging or decapitation, can be mobilized by electrical stimulation for up to 3 hours. By administering spinal cord stimulation by applied paddles to the cord or transcranial magnetic stimulation to M1 and recording evoked potentials, it should be possible to test fusogens in fresh cadavers. Delayed neuronal death might be the neuropathological reason. [CAN 16]
It is doubly relevant to the history of cadaver experiments: on the one hand, a fresh cadaver can serve as an experimental substitute for the animal model; on the other hand, it allows us to explore the neuropathological foundations of the process of dying. Canavero placed his research in the context of isolated neuronal cell cultures:
Testing on brain dead organ donors in the interval between declaration of brain death and initiation of organ harvesting is an ethical option. Reviewed data from two centuries ago prove that another ethical option is available, that is, experimentation on fresh cadavers. As discussed, movements can be elicited in a fresh cadaver by electrical stimulation for up to 3 hours (and possible more). This suggests that the cerebral cortex and its projections to the spinal cord and the cord itself remain viable for up to 3 hours postmortem. This includes both the cell bodies and the synapses. […] spinal cord stimulation above the level of attempted fusion or transcranial magnetic stimulation to M1 followed by recording motor evoked potentials (MEP) should be enough to confirm neuropshysiological conduction. [CAN 16]
While the scientific dimension seems to fall back into the spectacular and the announcement effect, it seemed relevant to point out the continuous resurgence of the electric imagining as a material for life.
Thus, an electrical culture, plastic and polymorphic, was born and evolved during the 19th Century: a spark of life, the guarantor of a moral order, the substrate of individual temperaments, it marked the history of physiology, medicine, philosophy and literature. The next chapters will look at how these different stages are broken down and how they give rise to knowledge, practices and techniques that are still relevant today.
1 1 Bertholon alludes, in this passage, to the research of Nicolas, M. “Experiments made on some animals fallen into asphixia caused by coal vapors”, in Observations sur la physique, sur l’histoire naturelle et sur les arts, [NIC 86, p.231, author’s translation].
2 2 The muscle referred to in this quote from Aldini is the heart.
3 3 A Franco-Belgian physiologist, Nysten, together with Bichat, conducted pioneering electromedical experiments, particularly in connection with the determination of the stages of rigor mortis, described in 1811 and known as “Nysten’s law”. This research cannot be detached from experiments on the galvanization of the heart, nor can it be detached from investigations into the length of time the tissue retains potential excitability.
4 4 To understand the atmosphere and the race of these physiologists and experimenters to obtain these bodies, it is exciting to read Nysten’s story of his adventure to arrive just at the moment when the tortured man gave his last breath. Thus he saw the announcement of execution, went urgently to the director of a medical school who could receive such a subject and assisted him in motivating the request: “I testify to him the desire that I have to try on the heart of man the experiments that I had already made on the hearts of several animal species. I add that we are going to torture a criminal, […] I obtain authorization by virtue of which the body of the person to be killed was placed at my disposal, after his beheading, […]. No sooner had I got there than I saw the fatal knife fall” [NYS 02, p. 18, author’s translation].
5 5 Ultimum moriens is Latin for the last thing to die. In cardiac anatomy it describes the right chamber of the heart, considered as still susceptible to contraction after the rest of the heart and as the last part to stop.
6 6 Historically, this debate is part of older quarrels about the respective places of the heart and the brain. Moreover, it accompanies the progressive cerebralization of faculties. “Such a relationship is not self-evident and has not been established without difficulty. Aristotle and his school located the center of sensations in the heart, and gave the brain, a cold and humid organ, the only function of tempering the body’s internal heat. The idea that the brain is the center of intelligence is found in a cursive and often metaphorical way among some Presocratics, Hippocrates and Plato. But it was Galen (131–200) who, refuting Aristotle, provided the first systematic demonstration of this, based on convergent anatomical and pathological arguments” [LAP 70, p. 599, author’s translation].
7 7 Aware of the ambiguities of the state of proven death, Aldini underlined the fact that an individual can be paralyzed and alive or, on the contrary, moving and dead: “[…] that a man whose paralyzed limb refuses to undergo muscular contractions can very well be alive; whereas muscular contractions can easily be obtained by galvanism, or any other stimulant, in a subject who is truly deprived of life.” [ALD 04, pp. 222-226, author’s translation].
8 8 These preoccupations to differentiate between the state of life and that of death were developed during the 19th Century [DES 51; CAR 15].
9 9 “Execution of Weems”, Cambridge Chronicle and Journal, August 13, 1819.
10 10 William Sturgeon is known to have introduced the first electromagnet in 1825. In 1832, he introduced the first electric motor. In 1836, he published the journal Les Annales de l’Électricité СКАЧАТЬ