Fields, editor-in-chief of Neuro Glia Biology, has written a book about a revolutionary discovery that is overturning a century of conventional thinking about how the brain operates at a cellular level. "All of our ideas about how the brain works are based on the neuron doctrine, which is that all information in the brain is communicated by electrical impulses in neurons across synapses," Fields writes: "Scientists are startled to learn that this fundamental assumption is wrong." Only 15 percent of the cells in our brain are neurons; the other 85 percent (glia) have been largely dismissed as little more than packing material for neurons. Recently scientists have learned that glia communicate among themselves without using electricity.