>Each octopus tentacle, however, acts autonomously as it feels around for food or threats. The brain can take over if necessary, but their decentralised nervous systems make octopuses less dependent than vertebrates on transmitting long-range signals through their bodies.

The only way I could imagine this is by holding hands of two toddlers. They are attached to you, acting autonomously, but you could (pretty much) order them around.

It's like trying to imagine what it's like to be blind, you can't.