Joseph Erlanger was born in 1874 in St. Francisco. In 1899, he was qualified at Johns Hopkins University to practice medicine and engaged in the research of blood pressure. Later on, he headed the Physiology Department at the Schools of Medicine of Wisconsin and Washington Universities.

In 1944, Joseph Erlanger and his colleague, Herbert Gasser, were jointly awarded the Nobel Prize in Medicine and Physiology “for their discoveries relating to the highly differentiated functions of single nerve fibers”.

Erlanger and Gasser were the first to succeed in performing a detailed measurement of the action potential of a signal nerve cell, by means of an oscilloscope device built by them from a cathode ray tube and an amplified.

Their measurements exposed 3 main types of nerve fibers, and also that the velocity of the electrical current varies according to a direct relation with the width of the fiber. Inasmuch as the fiber is wider, the velocity is increased.

The experiments conducted by Erlanger and Gasser as from 1921 served as a basis to the modern knowledge on action potentials in nerves and were very important in the understanding of various functions of nerve tissues.

Joseph Erlanger died in 1965.