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Published in Anton Sebastian, A Dictionary of the History of Medicine, 2018
Bell–Magendie Law Law governing the part played by ventral (or motor) and dorsal (or sensory) nerve roots in reflex nerve conduction of the spinal cord. Formulated independently by Charles Bell (1774–1842) in 1811 and François Magendie (1783–1855) in 1822. See autonomic nervous system.
The Return Of The Reflex
Published in Andrew P. Wickens, A History of the Brain, 2014
Magendie published a brief communication of his discovery in 1822, and later backed it up with more substantial research. Although Magendie acknowledged Bell was the first to attribute the anterior roots with a motor function, he claimed priority for demonstrating the sensory nature of the posterior roots. It was a claim Bell would strongly dispute, leading to an acrimonious and longlasting rivalry between the two men. This situation was not helped by anti-French sentiment of the times, and the cruelty of Magendie’s experiments. The conflict was to last until Bell’s death in 1842. Today, most historians accept Magendie was justified in his claims, with Bell providing little evidence to indicate the sensory nature of the posterior roots.8 However, regardless of who was right, the two men had between them established an important new neurological concept: that is, there are separate motor and sensory pathways in the spinal cord. In short, the motor fibres leave the spinal cord through its anterior roots, whereas sensory fibres enter the spinal cord by its posterior roots. This arrangement is now known as the Bell–Magendie law and it was to provide a crucial advance in understanding reflexive action.
First Half of the Nineteenth Century
Published in Arturo Castiglioni, A History of Medicine, 2019
An investigator of all sorts of isolated phenomena and always ready to experiment in any field of science, he called himself a “rag-picker” who would gather up anything that he found in his path. He was a fervent apostle of animal experimentation. Anyone who studies the work of this destructive critic and revolutionist in physiological method must recognize that he sometimes went too far in setting down without critical analysis experimental results that could not withstand a strict objective examination. However, his work on cardiac function, on digestion, on the importance of the blood in disease, his study of typhus by the intravenous injection of virulent material, his injections of egg albumin into the veins of rabbits, and his pharmacological studies on the localization of the site of drug action (which gave a scientific basis for the introduction into practice of such drugs as strychnine, morphine, and veratrine) constitute his imperishable claims to the gratitude of science. He was the first to show adequately that section of the anterior roots of the spinal cord affected motility but not sensation, and vice versa as to the posterior roots. Thus he completed the work of Bell, who had merely observed that the posterior roots could be cut “without convulsing the muscles” while a mere touch of the anterior roots caused convulsions. The so-called Bell-Magendie law was confirmed by Fodera and Bellingeri, and in 1831 by Johannes Muller. In Magendie’s words: “I had under my eye the posterior roots of the lumbar and sacral nerves, and raising them successively with the blades of small scissors, I could cut each, the cord remaining intact. … I first thought that the limb corresponding to the cut nerves would be entirely paralysed; it was insensible to pricks and to stronger pressure. It seemed to me to be immobile; but soon, to my surprise, I saw that it moved distinctly although sensation was entirely absent. The second and third experiments gave me exactly the same result; I began to regard it as probable that the posterior roots of the spinal nerve could have different functions from the anterior roots, and that they were especially concerned with sensation.”
Adolf Kussmaul (1822–1902), and the naming of “poliomyelitis”
Published in Journal of the History of the Neurosciences, 2022
Nadeem Toodayan, Eric Matteson
Kussmaul’s second case concerned an 18-year-old farm girl named Sybille Prinzbach, who developed a wasting paralysis of the lower limbs soon after strolling through the Kinzig river in 1871. “Within eight days” of the onset of a prodromal illness characterized by lethargy, anorexia, and excruciating pain in the back and lower limbs, “there was complete paralysis of the legs” and “the patient noticed a rapidly increasing emaciation” in the same. Kussmaul promptly diagnosed her with acute anterior myelitis, noting specifically—in concordance with the Bell-Magendie law of spinal innervation (Drouin, Kwiatkowski, and Hautecoeur 2022)—the absence of sensory symptoms, and normal bowel and bladder function. “Despite her misfortune she was always cheerful.”
Neuroanniversary 2022
Published in Journal of the History of the Neurosciences, 2022
In 1822, French physiologist François Magendie (1783–1855) published his well-known study, Experiences sur les fonctions des racines des nerfs rachidiens, verifying the differentiation between sensory and motor nerves in the spinal cord, now referred to as the Bell-Magendie law. He was a member of the faculty of the College of France, holding the Chair of Medicine from 1830 to 1855.