Ewald Hering

Infobox Scientist
name = Ewald Hering
birth_date = August 5, 1834
birth_place = Alt-Gersdorf, Saxony
death_date = January 26, 1918
death_place = Leipzig, Saxony
residence =
citizenship =
nationality = Germany
ethnicity =
field = physiology
work_institutions =
alma_mater =
doctoral_advisor =
doctoral_students =
known_for = color vision
influences =
influenced =
prizes =
religion =
footnotes =

Karl Ewald Konstantin Hering (August 5, 1834 – January 26, 1918) was a German physiologist who did much research into color vision and spatial perception. His uncle was the homeopath Constantine Hering.

Born in Alt-Gersdorf, Kingdom of Saxony, Hering studied at the University of Leipzig and became a professor at Charles University in Prague.

Color theory

Hering disagreed with the leading theory developed mostly by Thomas Young and Hermann von Helmholtz.cite book |author=Turner, R. M. |title=In the eye's mind: vision and the Helmholtz-Hering controversy |publisher=Princeton University Press |location=Princeton, N.J |year=1994 |pages= |isbn=0-691-03397-8 |oclc= |doi=] Helmholtz's theory stated that the human eye perceived all colors in terms of three primary colors: red, green, and blue. Hering instead believed that the visual system worked based on a system of color opponency, a proposal now widely recognized as correct.

Hering looked more at qualitative aspects of color and said there were six primary colors, coupled in three pairs: red-green, yellow-blue and white-black. Any receptor that was turned off by one of these colors, was excited by its coupled color. This results in six different receptors. It also explained afterimages. His theory was rehabilitated in the 1970s when Edwin Land developed the Retinex theory that stated that whereas Helmholtz's colors hold for the eye, in the brain the three colors are translated into six.

Other research

In 1861 Hering described an optical illusion which now bears his name - Hering illusion. He also developed Hering's law of equal innervation to describe the conjugacy of saccades in animals.

The Hering-Breuer reflex is also named for him.

References

*Citation
id = PMID:11639585
url= http://www.ncbi.nlm.nih.gov/pubmed/11639585
last=Turner
first=R S
publication-date=1993
year=1993
title=Vision studies in Germany: Helmholtz versus Hering.
volume=8
issue=
periodical=Osiris
pages=80-103
*Citation
id = PMID:1303712
url= http://www.ncbi.nlm.nih.gov/pubmed/1303712
last=Baumann
first=C
publication-date=1992 Jun
year=1992
title= [Ewald Hering's opponent colors. History of an idea]
volume=89
issue=3
periodical=Der Ophthalmologe : Zeitschrift der Deutschen Ophthalmologischen Gesellschaft
pages=249-52
*Citation
id = PMID:9061228
url= http://www.ncbi.nlm.nih.gov/pubmed/9061228
last=Janko
first=J
publication-date=1995
year=1995
title=Mach and Hering's physiology of the senses.
volume=33
issue=
periodical=Clio medica (Amsterdam, Netherlands)
pages=89-96

External links

* [http://www.whonamedit.com/doctor.cfm/2647.html Who Named It?, Karl Ewald Konstantin Hering]