THE LIFE AND TIMES OF CHARLES SHERRINGTON

“GENIUS IS ONE PERCENT INSPIRATION ND NINETY NINE PERCENT PERSPIRATION”

The famous definition quoted above is attributed to American inventor Thomas Edison.

It is often quoted by people who have thought of a good idea but know that they must put in a lot of time and effort to create something or accomplish a goal. Though this quote is true of most geniuses, it is perhaps not true in the case of a few extraordinary scientists like Einstein, who is also supposed to have said “Genius is 1% talent and 99% percent hard work…” These two quotes in any case do not apply to poets whose works are only products of 100% genius e.g. Shakespeare, Valmiki, Vyasa, Homer, Kalidasa and Dante!

There are of course many other gifted scientists of varying percentage of these two factors. I leave it to the readers to work out the ratio in respect of their talents.

In this essay I have discussed the work of Charles Sherrington who at the end of the nineteenth century, explained the basic operation of the neuromuscular system.

During the Renaissance, Leonardo da Vinci had observed the movements of frogs with their heads cut off, and over one hundred years later René Descartes offered a mechanistic definition of the reflex action in animals. Al Brecht Vom Haller showed that nerve fibers in the body lead to the spinal cord and the brain. But throughout most of the nineteenth century, even after anatomists had mapped parts of it, the nervous system was viewed as a diffuse “protoplasmic network.” Sherrington’s explanation of how a system of nerve cells can control thousands of ordinary acts and events in the human body was a prepotent achievement— and the culmination of four hundred years of observation.

Charles Scott Sherrington was born on November 27, 1857, in Islington, a suburb of London. His father, James Norton Sherrington, was a physician who died while Charles was still young. His mother, Anne Brookes Sherrington, remarried, Caleb Rose, who was not only a physician but a cultivated gentleman, classically educated, and interested in geology and archeology. Rose had a strong influence on Sherrington, both in his decision to study medicine and in his broad intellectual reach.

Although interested in art and philosophy, Sherrington attended the Royal College of Surgeons and received his medical degree from Gonville and Caius College, Cambridge, in 1884. Sherrington was still a student when his first paper was read to the Royal Society: an anatomical study of a dog whose forebrain had been removed, with little apparent consequence, by F. L. Goltz several years before.

In his early career, however, Sherrington was not committed to neurology. In 1885 he and other physicians traveled to Spain to investigate a cholera epidemic, where at considerable danger to themselves they performed numerous autopsies on victims. Subsequently, he met Rudolph Virchow, in Berlin and took a six-week course with Robert Koch. For a time he intended to enter bacteriology, but when he returned to England, Sherrington began to turn away from pathology. He came under the sway of the noted physiologist W. H. Gaskell and opted to work on the problems of the spinal cord and reflex action. In 1887 he was appointed lecturer in systematic physiology at St. Thomas Hospital and elected a fellow at Cambridge.

When Sherrington began his work, relatively little was known of the nervous system, and the theory of the cell as the basic unit of life, established by Virchow, was scarcely a generation old. The nerves were known to have electrical properties. In some the spinal cord had been sectioned and mapped Initially; Sherrington continued research in this vein and in 1891 published his “Note on the knee Jerk.” By 1894 he recognised a fundamental difference between motor nerves, which deliver instructions to muscles and the “proprioceptors” a term he coined), which transmit information in the opposite direction. As a consequence, a picture began to emerge in which the central nervous system performs an integrative role in coordinating and operating the muscular apparatus.

Blinking, walking, breathing, and a myriad of other actions share a general explanation, which Sherrington provided. When the knee is tapped sharply, for example, the leg extends involuntarily and immediately falls back. Certain muscles contract to force the leg to straighten while others relax. Sherrington developed the concepts ofp innervation and inhibition to describe this process, which involves a reciprocal connection between the two sets of muscles. Many other relationships of the same order were discovered throughout the nervous system, and Sherrington formulated his generalisation in the following way: “The whole quantitative grading of the operations of the spinal cord and brain appears to rest upon mutual interaction between the two central processes, excitation and inhibition, the one no less important than the other.”

The thorough explanation of what is sometimes called the “vegetative system” of involuntary neuromuscular control is by no means Sherrington’s alone, but it was he who integrated, into the growing body of neurological knowledge major concepts and discoveries made by others. Most notably, he incorporated the insight that the nervous system is not made up of fibres but of cells, which belongs to the Spanish neuroanatomist Santiago Ramón y Cajal. Recognising the interface between Cajal’s notion of nerve cell and his own work on reflexes, Sherrington in 1897 suggested the term” synapse” to describe the transmission of impulse from one of these neurons to the next, creating an evanescent but reliable pathway. The notion of the synapse put an end to the “reticular” theory that nerve fibres formed a diffuse protoplasmic network throughout the body.

When The Integrative Action of the Nervous System was published in 1906, Sherrington was compared to Sir Isaac Newton, and to William Harvey. The book immediately became a standard and remains the classic text in neurophysiology. In 1913, Sherrington was named Wayneflete professor of physiology at Oxford, but World War I soon interrupted his research. During the war Sherrington, then in his fifties, took unskilled jobs in factories in order to study the problem of fatigue for the British War Office. After the war he continued his neurological work and served as president of the Royal Society from 1920 to 1925. At Oxford, Sherrington acquired an international reputation, and his influence was spread worldwide by his students. His Reflex Activity of the Spinal Cord was published in 1932, the year in which he was awarded the Nobel Prize for medicine or physiology, shared with Edgar D. Adrian.

Sherrington’s work on the central nervous system extended to the brain. He published a mapping of the motor cortex in the primate brain, which encouraged further research. In addition, he brought evolutionary concepts to bear on neurophysiology and neurology, showing that the higher centres of the central nervous system have an inhibitory effect on the lower centres. However, in The Brain and Its Mechanisms in 1933, he declared,

“We have to regard the relation of mind to brain as not merely unsolved but still devoid of a basis for its very beginning.” For his acceptance of and reflections on mind/body dualism, Sherrington was sometimes called “the philosopher of the nervous system.” But it should be pointed out that, although advances have been made and a variety of theories proposed, a satisfactory explanation of brain function is still lacking mainly because of the extremely complex nature of the subject, which demanded extraordinary genius, perseverance and hard work.

Sherrington also wrote for a general audience. He published the expansive, widely read “Man on His Nature” in 1940, espousing what has been called a sort of “evolutionary pantheism.” He also wrote a biography of the French physiologist Jean Ferel, a book on Goethe, and a volume of poetry, The “Assaying of Brabantius”.

In addition to his literary pursuits, Sherrington was a bibliophile and an art aficionado; he loved music and drama. He had a special affection for the French language and culture, and he and his wife frequently visited France. Sherrington had married Ethel Mary Wright in 1891, and their only child, Carr E. R. Sherrington, became a well-known economist. Sherrington’s sensitive side caused his biographer, Ragnar Granit, to comment, “The wide emotional register of a Sherrington, a Ramón y Cajal, a Pascal is one of the traits most difficult to reconcile with what is known about their work as great experimenters or accurate thinkers in wholly unemotional terms.”

Charles Sherrington died at the age of ninety-five following a heart attack on March 4, 1952, at Eastbourne, Sussex. In the hall of fame of neuroscientists, he ranks alongside Paul Broca, and Santiago Ramon. Y Cajal. So does his equally brilliant contemporary Edgar Adrian.