Bell–Magendie law
In anatomy and neurophysiology, this is the finding that the anterior spinal nerve roots contain only motor fibers and posterior roots only sensory fibers and that nerve impulses are conducted in only one direction in each case. The nature and the physiology of the phenomena were described independently by the British anatomical scientist Sir Charles Bell and the French physiologist François Magendie, later confirmed by the German physiologist Johannes Peter Müller.
The naming controversy[edit]
The dispute of the findings, and subsequently the naming of the discovery, started with the publication of Magendie's paper in the Journal de physiologie expérimentale et de pathologie. The conflict lasted until Bell's death in 1842. Some science historians have better resolved to name it after both physicians, giving Bell the honorary first mention, although others have claimed that these are essentially two overlapping discoveries. Because of the independent findings of both scientists (Bell's claim over the motor function and Magendie's over the sensory function) and the existing conflict between England and France on the political arena of the 19th century (and prior to that), the debate on the Bell–Magendie law became a matter of national pride. The English medicine professors, especially Bell, and even English politicians rebuked the "crude methods" of the French vivisectionist. English medical staff and faculty were more tuned into seeking anatomical and structural explanations through dissections – taking a sort of medical functionalist approach. The dispute between the two happened in an era of a more secular approach to scientific discovery; positivism had become popular in many sciences. That was at about the same time as the works and theories of Auguste Comte were published.
On the other hand, Magendie was considering himself in his own words "a mere scavenger of science trying to do science by collecting bits and pieces of nature's truths"; he was not after the grand scheme but after the "inventory of the nuts and bolts of the system".[8] The French were also proud with Magendie's many discoveries and the extension of human knowledge in the areas of pathology, physiology and pharmacology and stood firmly behind his claim on the matter. Nevertheless, many Frenchmen (and most of our contemporaries) would have agreed with the English that the vivisections were not for the faint of heart. Until his death in 1842, Bell would write against the methods of Magendie and in his letters and books he would disapprove of the "protracted cruelty of the dissection experiments"[9]
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Exceptions[edit]
The unmyelinated Group C nerve fibers that transmit pain and temperature from the pelvic viscera enter the spinal cord via ventral roots at L5-S3, thus violating the Bell–Magendie law.