The Gatekeepers of Sensation

James N. Sleigh CC BY-NC

What resembles a stained-glass window is nearly one hundred slices of bundled cell bodies of a mouse peripheral nerve — a fraction as thick as human hair. Stack them up and they form one complete dorsal root ganglion, a modest bulge where nerve fibers run together before entering the spine. At this confluence, neurons wrangle heat, pain, and touch signals coming in from fingers, toes, and other extremities, before the spine whisks them away to the brain.

Dorsal root ganglia (you have a few dozen) have captured academic and medical interest for their role as pain and sensory gateways. Damaging them can trigger tingling or burning in the hands and feet that can last for years. Directly treating the bundles with drugs or heating them with radio waves can provide relief for some types of back pain and arthritis. Clear images like this one let researchers map every neuron in the entire ganglion.

About the Author

Charlie Wood

Charlie Wood is a science writer with a bachelor’s degree in physics from Brown University and a master’s degree in science journalism from New York University. In previous lives he taught physics in Mozambique and English in Japan, but these days he freelances from his home in New York.