Fig. 2.

A-C. Photographs of individuals who had a major influence on concepts regarding the cellular composition of the human brain. This composite shows the three main proponents of the 10:1 glia-neuron ratio and the notion of one trillion glia cells in the human brain. A. Holger Hydén was a professor at the University of Goteborg, Sweden, and the first to claim a 10:1 glia-neuron ratio in the 1960s (Hyden, 1960, 1967). Photo: Courtesy of Anders Hamberger, photography: Lennart Nilsson. Reproduced with permission. B. Stephen Kuffler, professor at Harvard and the “father of modern neuroscience,” was the first to promote the “at least 10:1 ratio” in his influential textbook in 1976 (Kuffler and Nicholls, 1976). Photo by Bachrach, Boston. Reproduced with permission. C. Eric Kandel, professor at Columbia University and Nobel laureate (2000), contributed to the perpetuation of the notion of one trillion glial cells by stating that glia outnumber neurons 10–50fold in his many editions of “Principles of Neural Science” – the “bible of neuroscience” visible in the bookshelf (Kandel and Schwarz, 1981 Kandel and Schwarz, 1985). Photo credit: Columbia University. Reproduced with permission.