In 1937 the great neuroscientist Sir Charles Scott Sherrington of the University of Oxford laid out what would become a classic description of the brain at work.He
imagined points of light signaling the activity of nerve cells and their connections.During deep sleep, he
proposed, only a few remote parts of the brain would twinkle, giving the organ the appearance of a starry night sky.But at awakening, "it is as if the Milky Way entered upon some cosmic dance," Sherrington
reflected."Swiftly the head-mass becomes an enchanted loom where millions of flashing shuttles weave a dissolving pattern, always a meaningful pattern though never an abiding one; a shifting harmony of subpatterns."
probably did not realize it at the time, his
poetic metaphor contained an important scientific idea: that of the brain revealing its inner workings optically.