In number of neurons, octopuses and their relatives far
exceed other invertebrates and put rodents, frogs, and many other vertebrates
to shame.
Pond snails have 0.01 million neurons; mouse 80 million;
octopus 500 million; and human has 86,000 million neurons.
An octopus’s nervous system processes information not just
in the brain but also throughout all eight arms and the suckers that line them.
The brain of octopus contains one-third of its neurons. It
handles higher executive functions, such as decision-making, learning, and
memory, as well as coordination of complex movements. Most of an octopus’s
neurons are in its arms. Each has interlinked control centers, or ganglia, that
relay information to the brain and also independently control movements such as
extending or twisting an arm.
(National Geographic magazine)
