Erlanger was born on January 5, 1874, in
San Francisco,
California. His Jewish father immigrated from
Buchau Kingdom of Württemberg,
Germany and his mother also immigrated from
Kingdom of Württemberg,
Germany, she was also Jewish. They got to know each other in California during the
Gold Rush. Joseph was the sixth of seven children born to the couple. He completed his
Bachelor of Science in Chemistry from the
University of California, Berkeley in 1895. He then completed his M.D. in 1899 from the
Johns Hopkins School of Medicine in
Baltimore,
Maryland, where he finished second in his class. Upon graduating, Erlanger interned at
Johns Hopkins Hospital under
William Osler and worked in a physiology laboratory. Erlanger also gave lectures at the school on digestion and metabolism. Erlanger also had an interest in
cardiology, specifically the way that excitation transferred from the
atrium to the
ventricle and researched with
Arthur Hirschfelder. Erlanger developed and patented a new type of
sphygmomanometer that could measure
blood pressure from the
brachial artery. While working at
Johns Hopkins School of Medicine in 1901, Erlanger published a paper on the digestive systems of canines. This paper caught the attention of
William Henry Howell, a
physiology professor at
Johns Hopkins School of Medicine. Howell recruited Erlanger as an assistant professor. Erlanger was promoted to associate professor some time before 1906. In 1906, Erlanger accepted a position as the first chair of physiology at the
University of Wisconsin in
Madison. In 1910, he left to take a position as professor at
Washington University in St. Louis; the St. Louis position offered Erlanger more funding for his projects. Herbert Spencer Gasser, Erlanger's former student at Wisconsin, joined Erlanger's laboratory soon after the move. During
World War I, the pair contributed to the research effort examining the effects of
shock. As part of this work, Erlanger was able to produce
heart block in an animal model by clamping the
bundle of His and tightening it. Together, they managed to amplify the action potential of a
bullfrog sciatic nerve in 1922 and published the results in the
American Journal of Physiology. It is uncertain why the pair had such a sudden shift in interest to
neuroscience, as Erlanger was already widely respected in the cardiology field. Erlanger was elected to the United States
National Academy of Sciences in 1922 and the
American Philosophical Society in 1927. Erlanger and Gasser were able to modify a
Western Electric oscilloscope to run at low voltages. Prior to this modification, the only method available to measure neural activity was the
electroencephalograph, which could only show large-scale electrical activity. With this technology, they were able to observe that action potentials occurred in two phases—a spike (initial surge) followed by an after-spike (a sequence of slow changes in potential). They discovered that
neurons were found in many forms, each with their own potential for excitability. With this research, the pair discovered that the velocity of action potentials was directly proportional to the diameter of the nerve fiber. The partnership ended in 1931, when Gasser accepted a position at
Cornell University. In 1944, they won the
Nobel Prize in
Medicine or Physiology for these discoveries. He died of heart disease on December 5, 1965, at
St. Louis,
Missouri. The
Joseph Erlanger House in St. Louis was designated a
National Historic Landmark on December 8, 1976, as a building of national significance. On January 22, 2009, the
International Astronomical Union named a
crater on the
Moon after him. ==Citations==