Octopus Arms Use 350 Million Neurons in Segmented Cords for Independent Control
Updated
Updated · spacewar.com · Aug 10
Octopus Arms Use 350 Million Neurons in Segmented Cords for Independent Control
3 articles · Updated · spacewar.com · Aug 10
Summary
University of Chicago researchers found each octopus arm contains a segmented axial nerve cord, with neuronal cell bodies arranged in repeating columns separated by septa that route nerves and blood vessels to nearby muscles and suckers.
About 350 million of an octopus’s 500 million neurons sit in its arms, letting local circuits process touch and start movements without waiting for the central brain to micromanage every action.
The team also mapped a “suckerotopy” — a built-in positional map of suckers inside the arm — helping explain how an arm identifies which sucker sensed something and bends the right segment toward it.
Comparisons with squid showed segmentation appears where dexterous, sucker-lined appendages need fine control, but not in bare tentacle stalks built mainly to launch and retract.
The finding, published in Nature Communications, is already informing soft-robotics designs that distribute control across local sensing units instead of relying on one central controller.