Johann Nepomuk Czermak (17 June 1828 – 16 September 1873) was an Austrian-German

physiologist Physiology (; ) is the scientific study of functions and mechanisms in a living system. As a subdiscipline of biology, physiology focuses on how organisms, organ systems, individual organs, cells, and biomolecules carry out chemical and ...

Biography

Czermak was born on 17 June 1828 in

Prague Prague ( ; ) is the capital and List of cities and towns in the Czech Republic, largest city of the Czech Republic and the historical capital of Bohemia. Prague, located on the Vltava River, has a population of about 1.4 million, while its P ...

. He studied in Prague,

Vienna Vienna ( ; ; ) is the capital city, capital, List of largest cities in Austria, most populous city, and one of Federal states of Austria, nine federal states of Austria. It is Austria's primate city, with just over two million inhabitants. ...

, Breslau and

Würzburg Würzburg (; Main-Franconian: ) is, after Nuremberg and Fürth, the Franconia#Towns and cities, third-largest city in Franconia located in the north of Bavaria. Würzburg is the administrative seat of the Regierungsbezirk Lower Franconia. It sp ...

. At Breslau he was greatly influenced by the work of physiologist

Jan Evangelista Purkyně Jan Evangelista Purkyně (; also written Johann Evangelist Purkinje) (17 or 18 December 1787 – 28 July 1869) was a Czech anatomist and physiologist. In 1839, he coined the term " protoplasma" for the fluid substance of a cell. He was one of th ...

(1787–1869). He became a professor at

Graz Graz () is the capital of the Austrian Federal states of Austria, federal state of Styria and the List of cities and towns in Austria, second-largest city in Austria, after Vienna. On 1 January 2025, Graz had a population of 306,068 (343,461 inc ...

in 1855, and proceeded to work at several European universities, including

Kraków , officially the Royal Capital City of Kraków, is the List of cities and towns in Poland, second-largest and one of the oldest cities in Poland. Situated on the Vistula River in Lesser Poland Voivodeship, the city has a population of 804,237 ...

(1856/57) and

Leipzig Leipzig (, ; ; Upper Saxon: ; ) is the most populous city in the States of Germany, German state of Saxony. The city has a population of 628,718 inhabitants as of 2023. It is the List of cities in Germany by population, eighth-largest city in Ge ...

(from 1869). Czermak was a member of the

Austrian Academy of Sciences The Austrian Academy of Sciences (; ÖAW) is a legal entity under the special protection of the Republic of Austria. According to the statutes of the Academy its mission is to promote the sciences and humanities in every respect and in every fi ...

. Just prior to his death in 1873, he founded a physiological institute in Leipzig called the "Spectatorium". He died on 16 September 1873 in Leipzig.

Contributions

Czermak is remembered for his contributions made in the field of

laryngology Laryngology is a branch of medicine that deals with disorders, diseases and Trauma (medicine), injuries of the larynx, colloquially known as the voice box. Laryngologists treat disorders of the larynx, including diseases that affects the voice, swa ...

. Along with

neurologist Neurology (from , "string, nerve" and the suffix -logia, "study of") is the branch of medicine dealing with the diagnosis and treatment of all categories of conditions and disease involving the nervous system, which comprises the brain, the ...

Ludwig Türck (1810–1868), he is credited for introducing the

laryngoscope Laryngoscopy () is endoscopy of the larynx, a part of the throat. It is a medical procedure that is used to obtain a view, for example, of the vocal folds and the glottis. Laryngoscopy may be performed to facilitate tracheal intubation during ge ...

into medicine. The laryngoscope was created by Spanish singing instructor Manuel Garcia (1805–1906) in 1854 — shortly afterwards, Czermak made modifications to the device, and it soon gained popularity in the medical world. Czermak is also credited for adapting the instrument for examination of the nose and

nasopharynx The pharynx (: pharynges) is the part of the throat behind the mouth and nasal cavity, and above the esophagus and trachea (the tubes going down to the stomach and the lungs respectively). It is found in vertebrates and invertebrates, though its ...

. He had a keen interest in

phonetics Phonetics is a branch of linguistics that studies how humans produce and perceive sounds or, in the case of sign languages, the equivalent aspects of sign. Linguists who specialize in studying the physical properties of speech are phoneticians ...

, performing extensive studies on the role of the voice and acoustic conditions of the throat, mouth and nasal cavities in the production of

consonant In articulatory phonetics, a consonant is a speech sound that is articulated with complete or partial closure of the vocal tract, except for the h sound, which is pronounced without any stricture in the vocal tract. Examples are and pronou ...

s.Johann Nepomuk Czermak
@

Who Named It ''Whonamedit?'' is an online English-language dictionary of medical eponyms and the people associated with their identification. Though it is a dictionary, many eponyms and persons are presented in extensive articles with comprehensive bibliograp ...

His name is associated with "Czermak's vagus pressure", described as mechanical pressure being applied to a location on the

carotid triangle The carotid triangle (or superior carotid triangle) is a portion of the anterior triangle of the neck. Anatomy Boundaries It is bounded: * Posteriorly by (the anterior border of) the sternocleidomastoid muscle, * Anteroinferiorly by (the sup ...

that causes a lowering of the

heart rate Heart rate is the frequency of the cardiac cycle, heartbeat measured by the number of contractions of the heart per minute (''beats per minute'', or bpm). The heart rate varies according to the body's Human body, physical needs, including the nee ...

and eventual

loss of consciousness Unconsciousness is a state in which a living individual exhibits a complete, or near-complete, inability to maintain an awareness of self and environment or to respond to any human or environmental stimulus. Unconsciousness may occur as the re ...

. He conducted research on spatial localisation of skin sensibility, and also demonstrated the influence of the nervus sympathicus in regards to excretion of

saliva Saliva (commonly referred as spit or drool) is an extracellular fluid produced and secreted by salivary glands in the mouth. In humans, saliva is around 99% water, plus electrolytes, mucus, white blood cells, epithelial cells (from which ...

. In addition, he made contributions towards understanding a disorder that would later be known as

Von Hippel–Lindau disease Von Hippel–Lindau disease (VHL), also known as Von Hippel–Lindau syndrome, is a rare disease, rare genetic disorder with multisystem involvement. It is characterized by visceral cysts and benign tumors with potential for subsequent malignant t ...

— showing that changes in the eyes' fundus was capillary angioma of the

retina The retina (; or retinas) is the innermost, photosensitivity, light-sensitive layer of tissue (biology), tissue of the eye of most vertebrates and some Mollusca, molluscs. The optics of the eye create a focus (optics), focused two-dimensional ...

. For a period of time, the term "Hippel–Czermak syndrome" was used to reference the condition.

Selected writings

* ''Physiologische Studien'', three parts, Wien 1854/55 ("Physiological Studies"). * ''Über das Verhalten des weichen Gaumens beim Hervorbringen der reinen Vocale'', Wien 1857 ("On the behavior of the

soft palate The soft palate (also known as the velum, palatal velum, or muscular palate) is, in mammals, the soft biological tissue, tissue constituting the back of the roof of the mouth. The soft palate is part of the palate of the mouth; the other part is ...

at producing the pure vowels"). * ''Der Kehlkopfspiegel und seine Verwerthung für Physiologie und Medizin. Eine Monographie'', Leipzig 1860 ("The laryngoscope and its usage for physiology and medicine. A

monograph A monograph is generally a long-form work on one (usually scholarly) subject, or one aspect of a subject, typically created by a single author or artist (or, sometimes, by two or more authors). Traditionally it is in written form and published a ...

"). * ''Populäre Physiologische Vorträge''. Wien 1869 ("Popular Physiological Lectures") * ''Gesammelte Schriften'', two volumes, Leipzig 1879 ("Collected Writings").Professorenkatalog der Universität Leipzig , catalogus professorum lipsiensis
(publications)

References

External links

Short biography, bibliography, and links on digitized sources
in the

Virtual Laboratory The online project Virtual Laboratory. Essays and Resources on the Experimentalization of Life, 1830-1930, located at the Max Planck Institute for the History of Science, is dedicated to research in the history of the experimentalization of life. T ...

of the

Max Planck Institute for the History of Science The Max Planck Institute for the History of Science (German: Max-Planck-Institut für Wissenschaftsgeschichte) is a scientific research institute founded in March 1994. It is dedicated to addressing fundamental questions of the history of knowled ...

Biography

Contributions

Selected writings

References

External links

Further reading