Peter Hegemann (born 11 December 1954) is a Hertie Senior Research Chair for Neurosciences and a professor of Experimental Biophysics at the Department of Biology, Faculty of Life Sciences, Humboldt University of Berlin, Germany.

[7] Having won a fellowship for his PhD thesis, Hegemann went to Syracuse University in 1985 as a postdoctoral fellow in Kenneth W. Foster's lab for a year.

[10][11] As part of his PhD project, he characterized this protein in Halobacterium salinarum, discovering that yellow light activates halorhodopsin.

[14] A 1984 article by Kenneth W. Foster of Syracuse University suggested that rhodopsins would also serve as light detector in the green alga Chlamydomonas reinhardtii.

[24] This came in the same year as another study by a collaboration between Karl Deisseroth, Edward Boyden, Feng Zhang, Georg Nagel and Ernst Bamberg, which found light could lead to action potential in cultured neurons expressing channelrhodopsin.

[25] Teaming up with Deisseroth, Hegemann continued advancing optogenetics by developing rhodopsin variants that could react faster and more accurately,[26] detect different wavelengths of light [27] and conduct different ions.

[28][29] Using optogenetic techniques, Hegemann and collaborators have confirmed that the unbalanced activity of excitatory and inhibitory neurons causes behavioral deficits of mental disorders.