Cochlear Explorers – Part I – Organ of Corti

ie15This series will discuss famous anatomists and their discoveries that led to our understanding of cochlear structure. When the tools of their trade are considered, as well as the methods used for specimen staining and other procedures of the time, it’s a wonder scientists ever found anything, let alone the microscopic structures of the cochlea.  We all know of the organ of Corti as part of the cochlear structure. In general, we know that it is a cellular layer on the basilar membrane, in which sensory hair cells are powered by the potential difference between the perilymph and the endolymph.  These are highly specialized structures that respond to fluid-borne vibrations in the cochlea with a shearing vector in the hairs of some cochlear hair cells.  Of course, our first structure of interest is the organ of Corti, named for our first Cochlear Explorer, a famous anatomist who explored the inner in the middle 19th century, but……

 Who Was Corti?

The city of Gambarana is in the province of Pavia in northwestern. By today’s standards it would be a “wide spot in the road” with only about 260 ie11inhabitants, but in 1822 at the time of the birth of Alfonso Giacomo  Gaspare Corti in 1822, Gambarana was a thriving municipality with over 1000 inhabitants.  Located 40 miles south of Milan,  the Cortis maintained a home that was all that remained of the family’s former fortunes.  As a noble family of the Italian Lombardy region, there was much science in the early life of young Alfonso, the oldest son of the Marchesa Gaspare Giuseppe Corti di San Stefano Belbo and the Marchesa Beatrice Malaspina di Carbonaro. From his youth, Alfonso was under the influence of his father’s scientific interests and probably obtained his interest in the auditory system from his father’s good friend Antonio Scapa. It is tempting to think that Scarpa may have encouraged the boy’s interest in medicine at such a young age that Corti could be considered a late offshoot of the great line of Bolognese medico-intellectuals comprising of four generations from Malpighi (thought to be the father of microscopic anatomy) through Valsalva and Morgagni to Cotugo and Scarpa.  Scarpa, while an influence, was never one of his professors as he died in 1840, eight years before Corti began his medical education.  As a medical student he enrolled first at the University of Pavia from 1841-1845 where he studied microanatomy with Bartolomeo Panizza and Mario Rusconi. In 1845, against paternal wishes, Corti moved to  Vienna to complete his ie13medical studies and to work in the anatomical institute of Joseph Hirtl, where in 1847 he received his degree in medicine under the supervision of professor Hyrtl, with a thesis on the bloodstream system of a reptile. Hyrtl then appointed him as his Second Prosector.
 
With the outbreak of the 1848 Revolution, Alfonso left Vienna, and after brief military service in Italy, made visits to eminent scientists in Bern, London, Paris, and elsewhere to further study the use of the microscope in anatomical research . By the beginning of 1850 Corti had received the invitation of the anatomist Albert Kölliker and had moved to Würzburg, where he made friends with Virchow. At the Kölliker Laboratory he began to work on the mammalian auditory system. Corti spent time in Utrecht, where he visited Professors Schroeder van der Kolk and Pieter Harting and learned to use methods to preserve several preparations of the cochlea. He returned to Würzburg to complete his study of at least 200 cochleas of man and different animals.In the years 1850/51, in the laboratory of Albert von Kölliker at the University of Würzburg, he described for the first time the sensory epithelium, the spiral ganglion, the tectorial membrane, and the stria vascularis of the inner ear. His famous paper: “Recherches sur l’organe de l’ouïe des mammiferes” appeared in 1851 in Kölliker’s journal “Zeitschrift für wissenschaftie6liche Zoologie“.
 
In the same year, after death of his father, Corti inherited father’s title Marchese de San Stefano Belbo and estate and moved back to Italy.   In 1855, he married the daughter from a neighboring estate, Maria Bettinzoli, with whom he had a daughter Bianca and a son Gaspare.  Maria dies in 1861, leaving him with the responsibility of rearing the children. Unfortunately, he was gradually developing arthritis deformans (reumatoid arthritis) and Corti’s last 15 years were further darkened by the inexorable progress of his crippling illness.  The management of his estate and the education of his two children gave substance and meaning to Corti’s life until his death at the age of fifty-four. Whatever the cause of his abandonment of scientific pursuits, it sorely disappointed his friends and colleagues but his family was pleased, as they appear to have felt that these academic studies were beneath the level of one who had inherited a title and an estate. Due to his twenty-two-year silence in the scientific world, all but a few fellow scientists had long forgotten him. He is now generally known for the organ in the cochlea, described by him, which at Kölliker’s suggestion was designated the organ of Corti…..the name so familiar to students of medicine, natural sciences, and audiology.   In 1876, on the second of October, he died at Corvino San Quirico.
 
Next week a look at another Cochlear Explorer……The Cells of Claudius

About Robert Traynor

Robert M. Traynor, Ed.D., MBA is the CEO and practicing audiologist at Audiology Associates, Inc., in Greeley, Colorado with particular emphasis in amplification and operative monitoring, offering all general audiological services to patients of all ages. Dr. Traynor holds degrees from the University of Northern Colorado (BA, 1972, MA 1973, Ed.D., 1975), the University of Phoenix (MBA, 2006) as well as Post Doctoral Study at Northwestern University (1984). He taught Audiology at the University of Northern Colorado (1973-1982), University of Arkansas for Medical Sciences (1976-77) and Colorado State University (1982-1993). Dr. Traynor is a retired Lt. Colonel from the US Army Reserve Medical Service Corps and currently serves as an Adjunct Professor of Audiology at the University of Florida, the University of Colorado, and the University of Northern Colorado. For 17 years he was Senior International Audiology Consultant to a major hearing instrument manufacturer traveling all over the world providing academic audiological and product orientation for distributors and staff. A clinician and practice manager for over 35 years, Dr. Traynor has lectured on most aspects of the field of Audiology in over 40 countries. Dr. Traynor is the current President of the Colorado Academy of Audiology and co-author of Strategic Practice Management a text used in most universities to train audiologists in practice management, now being updated to a 2nd edition.