From Clouds to the Brain. Celine Cherici

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СКАЧАТЬ long as he tried to provoke cardiac movements by connecting the heart to the central nervous system, it achieved little. It had to be detached, insulated and brought into direct contact with metals:

      Besides, in admitting even these different results, I do not see how it is possible to refuse acknowledging, that with respect to the stimulus of galvanism, there is a wide difference between the susceptibility of the muscles of the animal life, and those of the organic life. Again, supposing that the galvanic phenomena were the same in both sorts of muscles, the fact would prove nothing more […]. [BIC 39, pp. 261–262]

This experiment showed that cardiac movements reacted to a localized and direct galvanism, independently of a direct action of the brain. Bichat differentiated between the effects of galvanization on animal muscles, subject to the action of the brain, and on those of organic life, which depended only very occasionally on the will. So there was no direct action of the brain on the heart, nor any technical means of triggering it. The two organs did not cease to function simultaneously. The knowledge of the life of the organs but also the definition of death was one of the stakes of this research. The description of brain death, which was not completed until the middle of the 20th Century, depended on research on resuscitation and on the possibility of identifying all the stages that marked the boundaries between life and its cessation.

      Aldini also noticed that the cardiac function appeared to be subdued in some of the suppressed patients, while it was easily reactivated in all muscles in others. He used three procedures to verify the resumption of cardiac movement post-mortem:

       – by supplying the spinal cord with a lead cylinder inserted into the canal of the cervical vertebrae and then bringing one end of a silver arc over the surface of the heart and the other to the spinal cord framework. The heart, which in the individual subjected to galvanism still enjoyed great vitality, immediately presented very visible and quite strong contractions;

       – by supplying the nerves of the wave pair and the large sympathetic nerves without the help of a battery;

       – by means of Volta’s devices and making use in general of a battery composed of 50 silver discs and as much zinc with the cards soaked in a solution of muriate of soda.

      He noted in several decapitated people, very strong cardiac contractions and concluded that the tip of this organ was, of all its parts, the most mobile and the most sensitive to galvanic influence. The contractions produced by the last of these three processes were not only stronger but also longer lasting. In the same perspective of verifying or corroborating scientifically the irritability of the heart and thanks to electrophysiology applied to the body as a whole, he was able to test the different organs separately and together and to specify the duration of excitability during which they could still imitate the movements of life:

1. That if the mechanical irritation of the pin and scalpel excited, from the beginning, visible contractions in the intestines, heart and diaphragm; the same contractions were much stronger with the battery. 2. That when neither the heart nor the diaphragm was no longer irritated by the scalpel, the scalpel still excited contractions in the muscles of the extremities. 3. That after the intestines, the heart first lost galvanic susceptibility; then the diaphragm, and finally the muscles of the extremities. [ALD 04, p. 93, author’s translation]

      Thus, Aldini’s experiments on the actions of the heart muscle formed some of these whole-body demonstrations. The medical imaginary, deeply embedded in scientific explorations, could hardly be separated from them. While Aldini chose tortured bodies to experiment on, the reasons were not only related to the history of the links between the bodies of those condemned to death and the history of vesalian anatomy, but also, and perhaps above all, to the possibility of having subjects whose vital forces had not been altered by disease and in which the springs of the fibers were not destroyed. In addition to galvanizing excitable points on the body, Aldini also connected isolated brains to raise their reflex actions:

      I sawed the skull to determine the action of the battery on the different parts of the brain, in the same order as they were presented by the anatomical dissection. All these parts obeyed the force of galvanism; but the corpus callosum and the cerebellum gave a more lively action. [ALD 04, pp. 62–63, author’s translation]

      Excerpts from Aldini’s texts allow us to highlight an underlying questioning of the links between facial expressions caused by galvanization and possible thought content retained even after the cessation of visible life. The following passage retranscribes both this questioning, already found in the revolutionary period on the subject of decapitated heads just after the killing when the eyes or face are still affected by movement, and a scientific theme on the links between muscles and the mechanics of emotions that were discussed in more detail by Duchenne de Boulogne (1806–1875):

      So I placed the two heads of the torture victims horizontally on a table (sl. 4, fig. 6.), so that the two sections communicated with each other by animal moisture alone. It was wonderful, and even frightening, to see these two heads at the same time making horrible faces at each other, so that some of the spectators who did not expect such results, were truly frightened. […] Having removed the upper part of the skull by a dissection parallel to the base of the brain, I incized the meninges, and made an arc from one of the ears to the medullary substance: first I saw sharp convulsions in the facial muscles. […] I separated the lobes of the brain, and applied the arc to the corpus callosum and to the ears, and then to the lips: and there was a violent shock over all the head, and over all the muscles of the face. Some of the spectators even believed that the corpus callosum had been affected by a convulsion of its own […]. [ALD 04, pp. 73–74, author’s translation]

Thus, by applying localized galvanization directly to selected nerves and not to the spinal cord, Aldini used the expression experimental myology [ALD 04, p. 100], the only one capable of making the fixed and mobile points of muscles and the true term of their action sensitive to the eye. Did Aldini really seek to bring the dead back to life? Nothing is less certain. In any case, it appears that he did not seek to bring criminals back to life, but accident victims, drowning victims or suicides caught in an apparent and perhaps reversible death. Indeed, the industrialization of the 19th Century, accompanied by the growth of cities, created the study of new neuroses, a psychiatricization of mores but also an increasing suicide rate, as Brierre de Boismont points out:

      It is impossible not to notice, when going through them, that the study of suicide touches upon the great questions of our time, such as pauperism, work, salary, family, property, the future of craftsmen, the future of society perhaps, etc. All these subjects and many others find in the etiology of many teachings, at the same time as they reveal the depth of an evil that has claimed no less than 300,000 victims in France since the beginning of this century. [BRI 56, viii–ix, author’s translation]

      Thus, Aldini’s perspective was that of a public health problem affecting several countries and of emergency medicine coming to the aid of unfortunate people who, as soon as they died, may have already regretted their action:

      Nevertheless, it cannot be opposed that the help of galvanism should be given, together with any other, to these unfortunate people who, in despair, have sought their destruction by strangulation or other means. Such accidents are unfortunately all too frequent in large cities; and galvanism deserves all the more confidence because its application, in all these cases, suffers no delay. [ALD 04, p. 141, author’s translation]

      Helping people in distress, defining death, understanding it in the depth of its physiological mechanisms were the goals pursued by Galvani’s nephew who promoted galvanism as an instrument of medical philanthropy. In fact, if galvanization contributed to differentiate, beyond the absence of movement and consciousness, the living from the dead, then it could help to save people who were not dying:

      A host of facts have shown us СКАЧАТЬ