Peter Ludvig Panum

Peter Ludvig Panum (December 19, 1820 - May 2, 1885) was a Danish physiologist and pathologist. He was a professor at the University of Kiel (1853-1864), and afterwards a professor of physiology at the University of Copenhagen. The Panum Institute in Copenhagen is named in his honor.

In the mid-1850s, Panum is credited for being the first person to perform a systematic and comprehensive study of endotoxin, which he referred to at the time as a hypothetical "putrid poison". He believed that this substance was responsible for the symptoms observed in patients with sepsis. He also performed an important study regarding immunity and measles. This research was undertaken during a measles epidemic on the Faroe Islands in 1846. Panum also did scientific research concerning protein and its relationship to the body's metabolism.

In his studies of binocular vision, the eponymous Panum's fusional area is derived. This term is defined as the area on the retina of one eye over which a point-sized image can range, while still being able to provide a stereoscopic image with a specific point of stimulus on the retina of the other eye. Therefore, the region in visual space that we perceive "single vision" is Panum's fusional area, and objects in front and behind this region exist in physiological diplopia (double vision).