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Jean Pierre Flourens
Jean Pierre Flourens
Born	13 April 1794 Maureilhan, France
Died	6 December 1867(1867-12-06) (aged 73) Montgeron, France
Nationality	French
Known for	anesthesia
Scientific career
Fields	physiologist

Marie Jean Pierre Flourens (13 April 1794 – 6 December 1867), father of Gustave Flourens, was a French physiologist, the founder of experimental brain science, and a pioneer in anesthesia.

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In 1861, two scientists got into a very brainy argument. Specifically, they had opposing ideas of how speech and memory operated within the human brain. Earnest Aubertin, with his localistic model, argued that a particular region or the brain was devoted to each separate process. Pierre Gratiolet, on the other hand, argued for the distributed model, where different regions work together to accomplish all of these various functions. The debate they began reverberated throughout the rest of the century, involving some of the greatest scientific minds of the time. Aubertin and his localistic model had some big names on his side. In the 17th century, René Descartes had assigned the quality of free will and the human soul to the pineal gland. And in the late 18th century, a young student named Frans Joseph Gall had observed that the best memorizers in his class had the most prominent eyes and decided that this was due to higher development in the adjacent part of the brain. As a physician, Gall went on to establish the study of phrenology, which held that strong mental faculties corresponded to highly developed brain regions, observable as bumps in the skull. The widespread popularity of phrenology throughout the early 19th century tipped the scales towards Aubertin's localism. But the problem was that Gall had never bothered to scientifically test whether the individual brain maps he had constructed applied to all people. And in the 1840's, Pierre Flourens challenged phrenology by selectively destroying parts of animal brains and observing which functions were lost. Flourens found that damaging the cortex interfered with judgement or movement in general, but failed to identify any region associated with one specific function, concluding that the cortex carried out brain functions as an entire unit. Flourens had scored a victory for Gratiolet, but it was not to last. Gall's former student, Jean-Baptiste Bouillaud, challenged Flourens' conclusion, observing that patients with speech disorders all had damage to the frontal lobe. And after Paul Broca's 1861 autopsy of a patient who had lost the power to produce speech, but not the power to understand it, revealed highly localized frontal lobe damage, the distributed model seemed doomed. Localism took off. In the 1870's, Karl Wernicke associated part of the left temporal lobe with speech comprehension. Soon after, Eduard Hitzig and Gustav Fritsch stimulated a dog's cortex and discovered a frontal lobe region responsible for muscular movements. Building on their work, David Ferrier mapped each piece of cortex associated with moving a part of the body. And in 1909, Korbinian Brodmann built his own cortex map with 52 separate areas. It appeared that the victory of Aubertin's localistic model was sealed. But neurologist Karl Wernicke had come up with an interesting idea. He reasoned that since the regions for speech production and comprehension were not adjacent, then injuring the area connecting them might result in a special type of language loss, now known as receptive aphasia. Wernicke's connectionist model helped explain disorders that didn't result from the dysfunction of just one area. Modern neuroscience tools reveal a brain more complex than Gratiolet, Aubertin, or even Wernicke imagined. Today, the hippocampus is associated with two distinct brain functions: creating memories and processing location in space. We also now measure two kinds of connectivity: anatomical connectivity between two adjoining regions of cortex working together, and functional connectivity between separated regions working together to accomplish one process. A seemingly basic function like vision is actually composed of many smaller functions, with different parts of the cortex representing shape, color and location in space. When certain areas stop functioning, we may recognize an object, but not see it, or vice versa. There are even different kinds of memory for facts and for routines. And remembering something like your first bicycle involves a network of different regions each representing the concept of vehicles, the bicycle's shape, the sound of the bell, and the emotions associated with that memory. In the end, both Gratiolet and Aubertin turned out to be right. And we still use both of their models to understand how cognition happens. For example, we can now measure brain activity on such a fine time scale that we can see the individual localized processes that comprise a single act of remembering. But it is the integration of these different processes and regions that creates the coherent memory we experience. The supposedly competing theories prove to be two aspects of a more comprehensive model, which will in turn be revised and refined as our scientific techologies and methods for understanding the brain improve.

Biography

Flourens was born at Maureilhan, near Béziers, in the département of Hérault. At fifteen he began studying medicine at Montpellier, where he received the degree of doctor in 1813. In the following year he went to Paris, carrying an introduction from A. P. de Candolle, the botanist, to Georges Cuvier, who received him kindly, and took an interest in him. In Paris, Flourens engaged in physiological research, occasionally contributing to publications; and, in 1821, at the Athénée, he gave a course of lectures on the physiological theory of the sensations, which attracted much attention amongst men of science.^[1]

In 1815, Flourens pioneered the experimental method of carrying out localized lesions of the brain in living rabbits and pigeons and carefully observing their effects on motricity, sensibility and behavior. His intention was to investigate localisationism, i.e., whether different parts of the brain had different functions, as the Austrian physician Franz Joseph Gall, the founder of phrenology, was proposing.^{[citation needed]} The trouble was that Gall did not use a proper scientific approach to his affirmations. In 1825, Flourens was elected as a member to the American Philosophical Society.^[2]

Flourens was able to demonstrate convincingly for the first time that the main divisions of the brain were indeed responsible for largely different functions. By removing the cerebral hemispheres, for instance, all perceptions, motricity, and judgment were abolished. The removal of the cerebellum affected the animal's equilibrium and motor coordination, while the destruction of the brainstem (medulla oblongata) caused death. These experiments led Flourens to the conclusion that the cerebral hemispheres are responsible for higher cognitive functions, that the cerebellum regulates and integrates movements, and that the medulla controls vital functions, such as circulation, respiration and general bodily stability.^{[citation needed]} On the other hand, he was unable (probably because his experimental subjects have relatively primitive cortex) to find specific regions for memory and cognition, which led him to believe that they are represented in a diffuse form around the brain. So, different functions could indeed be ascribed to particular regions of the brain, but a finer localization was lacking.

Flourens, by destroying the horizontal semicircular canal of pigeons, noted that they continue to fly in a circle, showing the purpose of the semicircular canals.^{[citation needed]}

Flourens was chosen by Cuvier in 1828 to deliver a course of lectures on natural history at the Collège de France, and in the same year became, in succession to LAG Bosc, a member of the Institute, in the division "Economic rurale." In 1830 he became Cuvier's substitute as lecturer on human anatomy at the Jardin du Roi, and in 1832 was elected to the post of titular professor, which he vacated for the professorship of comparative anatomy created for him at the museum of the Jardin the same year. In 1833 Flourens, in accordance with the dying request of Cuvier, was appointed a perpetual secretary of the Academy of Sciences; and in 1838 he was returned as a deputy for the arrondissement of Béziers. In 1840 he was elected, in preference to Victor Hugo, to succeed Jean François Michaud at the French Academy; and in 1845 he was created a commander of the légion d'honneur, and in the next year a peer of France. In 1841, he was elected a foreign member of the Royal Swedish Academy of Sciences.^[1]

In March 1847 Flourens drew the attention of the Academy of Sciences to the anesthetic effect of chloroform on animals.^[1]

On the revolution of 1848 he withdrew completely from political life; and in 1855 he accepted the professorship of natural history at the Collège de France. He died at Montgeron, near Paris on 6 December 1867.^[1]

Opposition to Darwinism

Flourens was an opponent of Darwinism and criticized the idea of natural selection. In 1864, he authored Examen du livre du M. Darwin sur l'Origine des Espèces.^[3] He refuted the arguments of spontaneous generation.^[4]

He was a creationist and defended the fixity of species.^[5]^[6] Flourens criticized Charles Darwin for personifying nature. He argued that natural selection is a contradictory term as nature does not select.^[7] Flourens' book was never translated into English and no reviewers attempted to refute his arguments in detail. However, Thomas Henry Huxley took issue with his criticism of Darwinism, noting that "his objections to details are of the old sort, so battered and hackneyed on this side of the Channel, that not even a Quarterly Reviewer could be induced to pick them up for the purpose of pelting Mr. Darwin over again."^[7]

Bibliography

Besides numerous shorter scientific memoirs, Flourens published:

Essai sur quelques points de la doctrine de la revulsion et de la derivation (Montpellier, 1813)
Experiences sur le système nerveux (Paris, 1825)
Cours sur la génération, l'ovologie, et l'embryologie (1836)
Analyse raisonnée des travaux de G. Cuvier (1841)
Recherches sur le développement des os et des dents (1842)
Anatomie générale de la peau et des membranes muqueuses (1843)
Buffon, histoire de ses travaux et de ses idées (1844)
Fontenelle, ou de la philosophie moderne relativement aux sciences physiques (1847)
Théorie expérémentale de la formation des os (1847)
Œuvres complètes de Buffon (1853)
De la longévité humaine et de la quantité de vie sur le globe (1854), numerous editions
Histoire de la découverte de la circulation du sang (1854)
Cours de physiologie comparée (1856)
Recuesi des lloges historiques (1856)
De la vie et de l'intelligence (1858)
De la raison, du genie, et de la folie (1861)
Ontologie naturelle (1861)
Examen du livre du M. Darwin sur l'Origine des Espèces (1864).^[1]

References

^ ^a ^b ^c ^d ^e Chisholm 1911.
^ "APS Member History". search.amphilsoc.org. Retrieved 2021-04-06.
^ Flourens, Pierre (1794-1867) Auteur du texte (1864). Examen du livre de M. Darwin sur l'origine des espèces / par P. Flourens,...{{cite book}}: CS1 maint: numeric names: authors list (link)
^ Henry, Freeman G. (1999). Anti-Darwinism in France: Science and the Myth of Nation. Nineteenth-Century French Studies 27 3/4: 290-304.
^ Clark, Linda L. (1984). Social Darwinism in France. University of Alabama. p. 15. ISBN 978-0817301491
^ Simonton, Dean Keith. (2004). Creativity in Science: Chance, Logic, Genius, and Zeitgeist. Cambridge University Press. p. 125. ISBN 0-521-83579-8
^ ^a ^b Huxley, Thomas Henry. (1880). Lay Sermons, Addresses, and Reviews. London: Macmillan & Co. pp. 314-319.

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