These records are from the Swedish neurophysiologist Yngve Zotterman’s experiments confirming the theories of the medicine laureate Corneille Heymans.
Nerve impulses are weak electrical currents that can be converted into sound. The recordings document nerve signals from the carotid sinus (a bulge in the carotid artery on the neck) of cats at different blood oxygen levels. Heymans’s research focused on the carotid sinus and how it regulates breathing, and Zotterman’s results further corroborated his hypotheses.
In 1939, when Heymans was awarded the 1938 Nobel Prize for Physiology or Medicine, the Second World War had just started, and the Nobel Prize laureates were unable to visit Stockholm. In a lecture on Swedish Radio, Zotterman used his own recording of nerve impulses in his presentation of Heymans’s research. He informed Heymans of the broadcast times, so he could listen to the presentation. Heymans understood the lecture even though it was in Swedish, and asked if he could have the recordings. This was probably when Zotterman added the descriptions in English which can be heard on these records. Heymans used them in his lectures for many years. When they were worn out, he asked Zotterman to send him new ones.
The records were donated to the Nobel Prize Museum in 2001.
