"Fluorescent nerves allow for exploration of the most mysterious sense: touch  A new technique for color-coding nerves involved in touch gives neuroscientists a much-needed tool for studying that mysterious sense. For nearly 250 years, the intricate detail and complexity of skin's nervous-system wiring has thwarted attempts at understanding it. But if researchers studying skin could be imagined as technicians reverse-engineering a supercomputer's peripherals, they'd have just traced about four lines back to the motherboard. ""Of all five major senses, the skin sense is the least understood. It's an enormous frontier, and this is a huge leap forward,"" said Jeff Woodbury of the University of Wyoming, a sensory biologist who co-authored a study of nerve endings Dec. 23 in Cell. ""With this technique we hope to unravel all of the different circuits of skin sensation."""