Jeff W. Lichtman is an American neuroscientist. He is the Jeremy R. Knowles Professor of Molecular and Cellular Biology and Santiago Ramón y Cajal Professor of Arts and Sciences at Harvard University. He is best known for his pioneering work developing the neuroimaging connectomic technique known as Brainbow.
Up to ~160 colours were observed in the first Brainbow mice. (a) A motor nerve innervating ear muscle. (b) An axon tract in the brainstem. c) The dentate gyrus. From Lichtman and Sanes, 2008.
Brainbow is a process by which individual neurons in the brain can be distinguished from neighboring neurons using fluorescent proteins. By randomly expressing different ratios of red, green, and blue derivatives of green fluorescent protein in individual neurons, it is possible to flag each neuron with a distinctive color. This process has been a major contribution to the field of neural connectomics.
Three brainbows of mouse neurons from Lichtman and Sanes, 2008
A brainbow of mouse neurons from Smith, 2007
A brainbow of neurons in a mouse embryo (b), as well as some tractographical images of similar neurons (Chédotal and Richards, 2010)