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[Anomalocaris]

A typical octopus has roughly as many neurons as a dog.     However, unlike a dog, more than half of an octopus’s neurons are not in its brain but in its tentacles.   The amount of neurons in an octopus’s tentacles allow each tentacle to execute its own neuromuscular coordination and complex autonomous behavior even if severed from the body of the octopus.     For example, a severed Octopus tentacle can still sense scent molecules in the water and feel it’s way through a maze to get to the food emitting the scent molecules on the other side.

Yet even though the octopus tentacle seems to have life of its own,   It obey commands issued by the brain.    If the maze is transparent so the octopus can see blind turns and dead ends in the maze,  tentacles attached to the octopus can avoid them while severed octopus tentacles can not.